MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Computerized Medical Imaging and Graphics' source. Thu, 09 Feb 2012 03:37:29 +0100 http://www.medworm.com/index.php?rid=5669947&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611112000134%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669947 Thu, 09 Feb 2012 08:13:42 +0100 5669947 http://www.medworm.com/index.php?rid=5669938&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611112000055%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669938 Thu, 09 Feb 2012 08:13:42 +0100 5669938 http://www.medworm.com/index.php?rid=5669946&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001509%2Fabstract%3Frss%3Dyes The authors regret that incorrectly numbered references appeared in Table 4 of this article. The authors would like to apologise for any inconvenience caused. A corrected Table 4 appears below. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669946 Thu, 19 Jan 2012 05:00:00 +0100 5669946 http://www.medworm.com/index.php?rid=5507985&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001443%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507985 Fri, 16 Dec 2011 20:44:34 +0100 5507985 http://www.medworm.com/index.php?rid=5507984&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001431%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507984 Fri, 16 Dec 2011 20:44:34 +0100 5507984 http://www.medworm.com/index.php?rid=5507975&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001261%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507975 Fri, 16 Dec 2011 20:44:34 +0100 5507975 http://www.medworm.com/index.php?rid=5669945&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001224%2Fabstract%3Frss%3Dyes Abstract: In this paper, we propose a framework to automate the assessment of the movements of a third cerebral ventricle in a cine MR sequence. Indeed, the goal of this assessment is to build an atlas of the movements of the healthy ventricles in the context of the hydrocephalus pathology. This approach is composed of two phases: a contour extraction, using fractional integration and a registration method, based on dynamic evolutionary optimization. The first phase of the framework is based on the fractional integration thresholding, that allows delineating the contours of the area of interest. In order to track over time each point of the primitive and achieve the assessment of the deformation, a matching method, based on a new dynamic optimization algorithm, called Dynamic Covariance Ma... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669945 Fri, 28 Oct 2011 04:00:00 +0100 5669945 http://www.medworm.com/index.php?rid=5669944&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001200%2Fabstract%3Frss%3Dyes Abstract: In this paper, a novel image registration method is proposed to achieve accurate registration between images having large shape differences with the help of a set of appropriate intermediate templates. We first demonstrate that directionality is a key factor in both pairwise image registration and groupwise registration, which is defined in this paper to describe the influence of the registration direction and paths on the registration performance. In our solution, the intermediate template selection and intermediate template guided registration are two coherent steps with directionality being considered. To take advantage of the directionality, a directed graph is built based on the asymmetric distance defined on all ordered image pairs in the image population, which is fundamen... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669944 Thu, 20 Oct 2011 04:00:00 +0100 5669944 http://www.medworm.com/index.php?rid=5669943&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001194%2Fabstract%3Frss%3Dyes Abstract: Due to physical limitations inherent in magnetic resonance imaging scanners, three dimensional volumetric scans are often acquired with anisotropic voxel resolution. We investigate several interpolation approaches to reduce the anisotropy and present a novel approach – constrained reverse diffusion for thick slice interpolation. This technique was compared to common methods: linear and cubic B-Spline interpolation and a technique based on non-rigid registration of neighboring slices. The methods were evaluated on artificial MR phantoms and real MR scans of human brain. The constrained reverse diffusion approach delivered promising results and provides an alternative for thick slice interpolation, especially for higher anisotropy factors. (Source: Computerized Medical Imaging an... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669943 Mon, 19 Sep 2011 04:00:00 +0100 5669943 http://www.medworm.com/index.php?rid=5199091&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001078%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199091 Thu, 08 Sep 2011 11:10:37 +0100 5199091 http://www.medworm.com/index.php?rid=5507981&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001029%2Fabstract%3Frss%3Dyes Abstract: In this work, we develop and validate an automated micro-computed tomography (micro-CT) image segmentation algorithm that accurately and efficiently segments bone, calcium phosphate (CaP)-based bone scaffold, and soft tissue. The algorithm enables quantitative evaluation of bone growth in CaP scaffolds in our study that includes many samples (100+) and large data sets (900 images per sample). The use of micro-CT for such applications is otherwise limited because the similarity in X-ray attenuation for the two materials makes them indistinguishable. Destructive characterization using histological techniques and scanning electron microscopy (SEM) has been the standard for CaP scaffolds, but these methods are cumbersome, inaccurate, and yield only 2D information. The proposed algori... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507981 Thu, 25 Aug 2011 04:00:00 +0100 5507981 http://www.medworm.com/index.php?rid=5669939&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001042%2Fabstract%3Frss%3Dyes Abstract: One major source affecting the precision of bone structure analysis in quantitative magnetic resonance imaging (qMRI) is inter- and intraoperator variability, inherent in delineating and tracing regions of interest along longitudinal studies. In this paper an automated analysis tool, featuring bone marrow segmentation, region of interest generation, and characterization of cancellous bone of articular joints is presented. In evaluation studies conducted at the knee joint the novel analysis tool significantly decreased the standard error of measurement and improved the sensitivity in detecting minor structural changes. It further eliminated the need of time-consuming user interaction, and thereby increasing reproducibility. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669939 Mon, 22 Aug 2011 04:00:00 +0100 5669939 http://www.medworm.com/index.php?rid=5669942&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000991%2Fabstract%3Frss%3Dyes This study directly compares morphological features of the mouse heart in its end-relaxed state based on constructed morphometric maps and atlases using principal component analysis in C57BL/6J (n=8) and DBA (n=5) mice. In probabilistic atlases, a gradient probability exists for both strains in longitudinal locations from base to apex. Based on the statistical atlases, differences in size (49.8%), apical direction (15.6%), basal ventricular blood pool size (13.2%), and papillary muscle shape and position (17.2%) account for the most significant modes of shape variability for the left ventricle of the C57BL/6J mice. For DBA mice, differences in left ventricular size and direction (67.4%), basal size (15.7%), and position of papillary muscles (16.8%) account for significant variability. (Sou... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669942 Mon, 08 Aug 2011 04:00:00 +0100 5669942 http://www.medworm.com/index.php?rid=5507979&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111001005%2Fabstract%3Frss%3Dyes Abstract: Medical images obtained with emission processes are corrupted by noise of Poisson type. In the paper the denoising problem is modeled in a Bayesian statistical setting by a nonnegatively constrained minimization problem, where the objective function is constituted by a data fitting term, the Kullback–Leibler divergence, plus a regularization term, the Total Variation function, weighted by a regularization parameter. Aim of the paper is to propose an efficient numerical method for the solution of the constrained problem. The method is a Newton projection method, where the inner system is solved by the Conjugate Gradient method, preconditioned and implemented in an efficient way for this specific application. The numerical results on simulated and real medical images prove the ef... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507979 Mon, 08 Aug 2011 04:00:00 +0100 5507979 http://www.medworm.com/index.php?rid=5199092&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100098X%2Fabstract%3Frss%3Dyes Pathologist and biologists have been using their tool of trade, the microscope, since the early 17th century and much of their analysis is visual. Microscopic imaging is now commonplace in a number of diverse fields such as medicine, biological research, cancer research, etc. Over the past two decades, enormous progress has been made in the development of microscopy imaging that has led to an explosive increase in the acquisition of digital image data. As a consequence, the automated analysis and quantification of microscopy images plays an increasingly important role in biosciences and systems biology. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199092 Tue, 12 Jul 2011 23:00:00 +0100 5199092 http://www.medworm.com/index.php?rid=5002528&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000644%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002528 Thu, 07 Jul 2011 17:15:44 +0100 5002528 http://www.medworm.com/index.php?rid=5002521&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000875%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002521 Thu, 07 Jul 2011 17:15:43 +0100 5002521 http://www.medworm.com/index.php?rid=5669940&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000796%2Fabstract%3Frss%3Dyes Abstract: A significant medical informatics task is indexing patient databases according to size, location, and other characteristics of brain tumors and edemas, possibly based on magnetic resonance (MR) imagery. This requires segmenting tumors and edemas within images from different MR modalities. To date, automated brain tumor or edema segmentation from MR modalities remains a challenging, computationally intensive task. In this paper, we propose a novel automated, fast, and approximate segmentation technique. The input is a patient study consisting of a set of MR slices, and its output is a subset of the slices that include axis-parallel boxes that circumscribe the tumors. Our approach is based on an unsupervised change detection method that searches for the most dissimilar region (axis... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669940 Mon, 04 Jul 2011 04:00:00 +0100 5669940 http://www.medworm.com/index.php?rid=5507983&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000802%2Fabstract%3Frss%3Dyes Abstract: Respiratory tract infections are a leading cause of death and disability worldwide. Although radiology serves as a primary diagnostic method for assessing respiratory tract infections, visual analysis of chest radiographs and computed tomography (CT) scans is restricted by low specificity for causal infectious organisms and a limited capacity to assess severity and predict patient outcomes. These limitations suggest that computer-assisted detection (CAD) could make a valuable contribution to the management of respiratory tract infections by assisting in the early recognition of pulmonary parenchymal lesions, providing quantitative measures of disease severity and assessing the response to therapy. In this paper, we review the most common radiographic and CT features of respirator... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507983 Mon, 04 Jul 2011 04:00:00 +0100 5507983 http://www.medworm.com/index.php?rid=5507980&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000826%2Fabstract%3Frss%3Dyes Abstract: Dual medical imaging modalities, such as PET-CT, are now a routine component of clinical practice. Medical image segmentation methods, however, have generally only been applied to single modality images. In this paper, we propose the dual-modality image segmentation model to segment brain PET-CT images into gray matter, white matter and cerebrospinal fluid. This model converts PET-CT image segmentation into an optimization process controlled simultaneously by PET and CT voxel values and spatial constraints. It is innovative in the creation and application of the modality discriminatory power (MDP) coefficient as a weighting scheme to adaptively combine the functional (PET) and anatomical (CT) information on a voxel-by-voxel basis. Our approach relies upon allowing the modality wi... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507980 Thu, 30 Jun 2011 04:00:00 +0100 5507980 http://www.medworm.com/index.php?rid=5199097&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100084X%2Fabstract%3Frss%3Dyes Abstract: Digital pathology provides new ways to visualize tissue slides and enables new workflows for analyzing these slides. Analogous to radiology, adjacent tissue sections prepared with different stains or biomarkers (e.g. H&E, IHC, special stains, or ISH; chromogenic or fluorescent) may be seen as different modalities, each representing different structural and/or functional information. Today, the anatomic pathologist views multiple glass slides using an optical microscope and then combines the information in their head to reach a (diagnostic) opinion. Moreover, due to the nature of the slide preparation and digitization process, the tissue and its features do not have the exact same morphology, appearance, or spatial alignment, making it difficult to find the same region on adjacent... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199097 Tue, 28 Jun 2011 23:00:00 +0100 5199097 http://www.medworm.com/index.php?rid=5669941&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000838%2Fabstract%3Frss%3Dyes In conclusion wavelet based clustering of DCE-MRI of kidney is feasible and a valuable tool towards automated perfusion and glomerular filtration rate quantification. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5669941 Mon, 27 Jun 2011 04:00:00 +0100 5669941 http://www.medworm.com/index.php?rid=5507982&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000814%2Fabstract%3Frss%3Dyes We present a new device which takes a different approach, as it leaves the volume in a fixed location and demands the user to change his or her posture to explore it from different angles. To implement this, we built a prototype based on a mobile display equipped with sensors that allows it to track its position, which is related to the location of the slice plane within the volume. Therefore, the user can manipulate this plane by displacing and rotating the display, which is a very intuitive method with minimum learning time. Furthermore, the postural changes required to use the device add a new channel of feedback, which effectively helps to reduce the cognitive load imposed on the user. We built a prototype device and tested it with two groups of volunteers who were asked to use it in a... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507982 Mon, 27 Jun 2011 04:00:00 +0100 5507982 http://www.medworm.com/index.php?rid=5199096&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000668%2Fabstract%3Frss%3Dyes We describe hardware and software tools for acquiring, viewing and processing the large image datasets (up to 400GB), validation studies investigating the clinical significance of the additional information gleaned from the 3D approach, and application to radiologic-pathologic correlation and biomarker visualization. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199096 Wed, 08 Jun 2011 23:00:00 +0100 5199096 http://www.medworm.com/index.php?rid=5002523&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000024%2Fabstract%3Frss%3Dyes Abstract: It is demonstrated that textural parameters calculated from functional pulmonary CT data have the potential to provide a robust and objective quantitative characterisation of inhomogeneity in lung function and classification of lung diseases in routine clinical applications. Clear recommendations are made for optimum data preparation and textural parameter selection.A new set of platform-independent software tools are presented that are implemented as plug-ins for ImageJ. The tools allow segmentation and subsequent histogram-based and grey-level co-occurrence matrix based analysis of the regions of interest. The work-flow is optimised for use in a clinical environment for the analysis of transverse Computed Tomography (CT) scans and lung ventilation scans based on SPECT. Consiste... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002523 Sun, 29 May 2011 23:00:00 +0100 5002523 http://www.medworm.com/index.php?rid=5002522&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001023%2Fabstract%3Frss%3Dyes Abstract: Three dimensional (3D) visualization of anatomy plays an important role in image guided orthopedic surgery and ultimately motivates minimally invasive procedures. However, direct 3D imaging modalities such as Computed Tomography (CT) are restricted to a minority of complex orthopedic procedures. Thus the diagnostics and planning of many interventions still rely on two dimensional (2D) radiographic images, where the surgeon has to mentally visualize the anatomy of interest. The purpose of this paper is to apply and validate a bi-planar 3D reconstruction methodology driven by prominent bony anatomy edges and contours identified on orthogonal radiographs. The results obtained through the proposed methodology are benchmarked against 3D CT scan data to assess the accuracy of reconstru... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002522 Sun, 29 May 2011 23:00:00 +0100 5002522 http://www.medworm.com/index.php?rid=4857633&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000681%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857633 Wed, 25 May 2011 18:09:02 +0100 4857633 http://www.medworm.com/index.php?rid=5507976&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000619%2Fabstract%3Frss%3Dyes Conclusion: The preliminary study demonstrates the feasibility of our MSCAR-DBT method for segmentation and tracking coronary artery trees. The results indicated that both our method and GE software can extract coronary artery trees reasonably well and the performance of our method is superior to that of GE software in this small data set. Further studies are underway to develop methods for improvement of the segmentation and tracking accuracy. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507976 Wed, 25 May 2011 04:00:00 +0100 5507976 http://www.medworm.com/index.php?rid=5199102&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000371%2Fabstract%3Frss%3Dyes Abstract: In this paper, we present a graph-based multi-resolution approach for mitosis extraction in breast cancer histological whole slide images. The proposed segmentation uses a multi-resolution approach which reproduces the slide examination done by a pathologist. Each resolution level is analyzed with a focus of attention resulting from a coarser resolution level analysis. At each resolution level, a spatial refinement by label regularization is performed to obtain more accurate segmentation around boundaries. The proposed segmentation is fully unsupervised by using domain specific knowledge. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199102 Thu, 19 May 2011 23:00:00 +0100 5199102 http://www.medworm.com/index.php?rid=5507977&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000607%2Fabstract%3Frss%3Dyes Abstract: Quantification of coronary arterial stenoses is useful for the diagnosis of several coronary heart diseases. Being noninvasive, economical and informative, computed tomographic angiography (CTA) has become a common modality for monitoring disease status and treatment effects. Here, we present a new method for detecting and quantifying coronary arterial stenosis in CTA using fuzzy distance transform (FDT) approach and a new coherence analysis of observed data for computing expected local diameter. FDT allows computing local depth at each image point in the presence of partial voluming and thus, eliminates the need for binarization, commonly, associated with inclusion of additional errors. In the current method, coronary arterial stenoses are detected and their severities are quant... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507977 Tue, 10 May 2011 04:00:00 +0100 5507977 http://www.medworm.com/index.php?rid=5199106&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000620%2Fabstract%3Frss%3Dyes Abstract: Using the fusion of pre-operative MRI and real time intra-procedural transrectal ultrasound (TRUS) to guide prostate biopsy has been shown as a very promising approach to yield better clinical outcome than the routinely performed TRUS only guided biopsy. In several situations of the MRI/TRUS fusion guided biopsy, it is important to know the exact location of the deployed biopsy needle, which is imaged in the TRUS video. In this paper, we present a method to automatically detect and segment the biopsy needle in TRUS. To achieve this goal, we propose to combine information from multiple resources, including ultrasound probe stability, TRUS video background model, and the prior knowledge of needle orientation and position. The proposed algorithm was tested on TRUS video sequences wh... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199106 Mon, 02 May 2011 23:00:00 +0100 5199106 http://www.medworm.com/index.php?rid=5199105&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000632%2Fabstract%3Frss%3Dyes Abstract: This paper proposes a new color correction pipeline to improve the dermoscopy image quality. Images acquired with different cameras or different dermoscopes often present problems of faithful color reproduction. The colors of these images are often far different the ones observed with the naked eye, and usually vary from one camera to another. Nowadays digital cameras perform “black-box” color corrections taking into account the color temperature of the imaged scene, which may result in some cases in unrealistic color rendering. For this reason, it is necessary to calibrate the imaging system (the camera and a specific dermoscope). The calibration process requires finding a relationship between a device-dependent color space and a standard color space depending only on the hu... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199105 Mon, 02 May 2011 23:00:00 +0100 5199105 http://www.medworm.com/index.php?rid=5002525&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001096%2Fabstract%3Frss%3Dyes Abstract: We demonstrate that the volume enclosed by triangulated surfaces can be computed efficiently in the same elegant way the volume enclosed by digital surfaces can be computed by digital surface integration. Although digital surfaces are effective and efficient for visualization and volume measurement, their drawback is that surface area measurements derived from them are inaccurate. On the other hand, triangulated surfaces give more accurate surface area measurements, but volume measurements and visualization are less efficient. Our data structure (called t-shell) for representing triangulated digital surfaces retains advantages and overcomes difficulties of both the digital and the triangulated surfaces. We create a lookup table with area and volume contributions for each of the 2... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002525 Sun, 24 Apr 2011 23:00:00 +0100 5002525 http://www.medworm.com/index.php?rid=5199101&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000449%2Fabstract%3Frss%3Dyes Abstract: Follicular Lymphoma (FL) accounts for 20–25% of non-Hodgkin lymphomas in the United States. The first step in grading FL is identifying follicles. Our paper discusses a novel technique to segment follicular regions in H&E stained images. The method is based on three successive steps: (1) region-based segmentation, (2) iterative shape index (concavity index) calculation, (3) and recursive watershed. A novel aspect of this method is the use of iterative Concavity Index (CI) to control the follicular splitting process in recursive watershed. CI takes into consideration the convex hull of the object and the closest area surrounding it. The mean Zijbendos similarity index (ZSI) final segmentation score on fifteen cases was 78.33%, with a standard deviation of 2.83. (Source: Computer... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199101 Thu, 21 Apr 2011 23:00:00 +0100 5199101 http://www.medworm.com/index.php?rid=5507978&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000462%2Fabstract%3Frss%3Dyes Conclusion: The proposed method provides a robust and fast automatic contouring for LV myocardium on arterial phase of MDCT. The potential role of this technique may save much of the time required to manually sketch a precise contour with high stability. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5507978 Fri, 15 Apr 2011 04:00:00 +0100 5507978 http://www.medworm.com/index.php?rid=5002526&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000450%2Fabstract%3Frss%3Dyes Abstract: An automated method for measurement of arteriolar-to-venular diameter ratio (AVR) is presented. The method includes optic disc segmentation for the determination of the AVR measurement zone, retinal vessel segmentation, vessel classification into arteries and veins, selection of major vessel pairs, and measurement of AVRs. The sensitivity for the major vessels in the measurement zone was 87%, while 93% of them were classified correctly into arteries or veins. In 36 out of 40 vessel pairs, at least parts of the paired vessels were correctly identified. Although the average error in the AVRs with respect to those based on the manual vessel segmentation results was 0.11, the average error in vessel diameter was less than 1 pixel. The proposed method may be useful for objective evalu... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002526 Wed, 13 Apr 2011 23:00:00 +0100 5002526 http://www.medworm.com/index.php?rid=4700667&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000486%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700667 Tue, 12 Apr 2011 23:17:59 +0100 4700667 http://www.medworm.com/index.php?rid=5002527&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000395%2Fabstract%3Frss%3Dyes Abstract: This paper describes a new method for classifying pigmented skin lesions as benign or malignant. The skin lesion images are acquired with standard cameras, and our method can be used in telemedicine by non-specialists. Each acquired image undergoes a sequence of processing steps, namely: (1) preprocessing, where shading effects are attenuated; (2) segmentation, where a 3-channel image representation is generated and later used to distinguish between lesion and healthy skin areas; (3) feature extraction, where a quantitative representation for the lesion area is generated; and (4) lesion classification, producing an estimate if the lesion is benign or malignant (melanoma). Our method was tested on two publicly available datasets of pigmented skin lesion images. The preliminary exp... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002527 Tue, 12 Apr 2011 23:00:00 +0100 5002527 http://www.medworm.com/index.php?rid=5199095&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000383%2Fabstract%3Frss%3Dyes Abstract: The histological assessment of human tissue has emerged as the key challenge for detection and treatment of cancer. A plethora of different data sources ranging from tissue microarray data to gene expression, proteomics or metabolomics data provide a detailed overview of the health status of a patient. Medical doctors need to assess these information sources and they rely on data driven automatic analysis tools. Methods for classification, grouping and segmentation of heterogeneous data sources as well as regression of noisy dependencies and estimation of survival probabilities enter the processing workflow of a pathology diagnosis system at various stages. This paper reports on state-of-the-art of the design and effectiveness of computational pathology workflows and it discusses... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199095 Sun, 10 Apr 2011 23:00:00 +0100 5199095 http://www.medworm.com/index.php?rid=5002524&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100036X%2Fabstract%3Frss%3Dyes This study presents numerical tools, based on biplanar radiography, allowing to analyze the 3D changes in position and length of the various spinal segments with respect to the pelvis which occur between the standing and sitting positions. Three asymptomatic adult subjects and twelve adult patients with low back pain or scoliosis had biplanar calibrated radiographs in the erect posture and sitting position. The 3D points of the spinal curve were then reconstructed from their plane projections using a standard photogrammetric technique. A technical data form has been formulated to present and summarize the complex 3D spino-pelvic changes occurring between both postures. The spine and pelvis are displayed as a chain of linear articulated segments, in their plane of maximum curvature, allowin... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5002524 Wed, 16 Mar 2011 00:00:00 +0100 5002524 http://www.medworm.com/index.php?rid=4586102&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000243%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586102 Tue, 15 Mar 2011 18:27:17 +0100 4586102 http://www.medworm.com/index.php?rid=5199098&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000218%2Fabstract%3Frss%3Dyes We present an interactive program called HistoStitcher© for accurate and rapid reassembly of histology fragments into a pseudo-whole digitized histological section. HistoStitcher© provides both an intuitive graphical interface to assist the operator in performing the stitch of adjacent histology fragments by selecting pairs of anatomical landmarks, and a set of computational routines for determining and applying an optimal linear transformation to generate the stitched image. Reconstruction of whole histological sections from images of slides containing smaller fragments is required in applications where preparation of whole sections of large tissue specimens is not feasible or efficient, and such whole mounts are required to facilitate (a) disease annotation and (b) image registration w... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199098 Mon, 14 Mar 2011 00:00:00 +0100 5199098 http://www.medworm.com/index.php?rid=4700674&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100022X%2Fabstract%3Frss%3Dyes Abstract: Accurate and fast fusion and display of real-time images of anatomy and associated data is critical for effective use in image guided procedures, including image guided cardiac catheter ablation. We have developed a piecewise patch-to-model matching method, a modification of the contractive projection point technique, for accurate and rapid matching between an intra-operative cardiac surface patch and a pre-operative cardiac surface model. Our method addresses the problems of fusing multi-modality images and using non-rigid deformation between a surface patch and a surface model. A projection lookup table, K-nearest neighborhood search, and a final iteration of point-to-projection are used to reliably find the surface correspondence. Experimental results demonstrate that the meth... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700674 Mon, 07 Mar 2011 00:00:00 +0100 4700674 http://www.medworm.com/index.php?rid=4700669&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000322%2Fabstract%3Frss%3Dyes Abstract: Clinical indications and utilization patterns for 3963 CT scans on 2500 consecutive patents on a 320-detector row CT in an outpatient setting were retrospectively analyzed and compared with previously reported CT studies. The impact of the latest generation CT technology, including whole organ perfusion, on indications and utilization patterns during the study period was also assessed. The top five requested CT scan types were abdomen/pelvis, chest, head, sinuses, and coronary CT angiography. Indication and utilization rates were similar to prior studies for abdomen/pelvis, non-cardiac chest, and head CT scans. Abdominal pain and headaches were the most frequent indications for abdomen/pelvis and head CTs, respectively. The 7.3% cardiac CT scan utilization rate was not comparable... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700669 Mon, 07 Mar 2011 00:00:00 +0100 4700669 http://www.medworm.com/index.php?rid=4700668&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000114X%2Fabstract%3Frss%3Dyes Abstract: In this paper, we address the issue of computer-assisted indexing in one specific case, i.e., for the 17,000 digitized images of the spine acquired during the National Health and Nutrition Examination Survey (NHANES). The crucial step in this process is to accurately segment the cervical and lumbar spine in the radiographic images. To that end, we have implemented a unique segmentation system that consists of a suite of spine-customized automatic and semi-automatic statistical shape segmentation algorithms. Using the aforementioned system, we have developed experiments to optimally generate a library of spine segmentations, which currently include 2000 cervical and 2000 lumbar spines. This work is expected to contribute toward the creation of a biomedical Content-Based Image Retr... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700668 Mon, 07 Mar 2011 00:00:00 +0100 4700668 http://www.medworm.com/index.php?rid=4700672&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000334%2Fabstract%3Frss%3Dyes Abstract: Image registration is the process of transforming different image data sets of an object into the same coordinate system. This is a relevant task in the field of medical imaging; one of its objectives is to combine information from different imaging modalities. The main goal of this study is the registration of renal SPECT (Single Photon Emission Computerized Tomography) images and a sparse set of ultrasound slices (2.5D US), combining functional and anatomical information. Registration is performed after kidney segmentation in both image types. The SPECT segmentation is achieved using a deformable model based on a simplex mesh. The 2.5D US image segmentation is carried out in each of the 2D slices employing a deformable contour and Gabor filters to capture multi-scale image feat... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700672 Thu, 03 Mar 2011 00:00:00 +0100 4700672 http://www.medworm.com/index.php?rid=4700670&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000061%2Fabstract%3Frss%3Dyes Abstract: The metric distance obtained from the large deformation diffeomorphic metric mapping (LDDMM) algorithm is used to quantize changes in morphometry of brain structures due to neuropsychiatric diseases. For illustrative purposes we consider changes in hippocampal morphometry (shape and size) due to very mild dementia of the Alzheimer type (DAT). LDDMM, which was previously used to calculate dense one-to-one correspondence vector fields between hippocampal shapes, measures the morphometric differences with respect to a template hippocampus by assigning metric distances on the space of anatomical images thereby allowing for direct comparison of morphometric differences. We characterize what information the metric distances provide in terms of size and shape given the hippocampal, brai... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700670 Wed, 23 Feb 2011 00:00:00 +0100 4700670 http://www.medworm.com/index.php?rid=5199103&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000206%2Fabstract%3Frss%3Dyes In this study, we propose an automated image analysis system for quantitative characterization of muscle fiber type composition. The proposed system operates on digitized histological muscle tissue slides and consists of the following steps: segmentation of muscle fibers, registration of successive slides with distinct stains, and classification of muscle fibers into distinct subtypes. The performance of the proposed approach was tested on a dataset consisting of 25 image pairs of successive muscle histological cross-sections with different ATPase stain. Experimental results demonstrate a promising overall segmentation and classification accuracy of 89.1% in identifying muscle fibers of distinct subtypes. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199103 Tue, 22 Feb 2011 00:00:00 +0100 5199103 http://www.medworm.com/index.php?rid=4700673&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000188%2Fabstract%3Frss%3Dyes Abstract: Present study proposes a computer-aided diagnostic system to assist radiologists in identifying focal liver lesions in B-mode ultrasound images. The proposed system can be used to discriminate focal liver diseases such as Cyst, Hemangioma, Hepatocellular carcinoma and Metastases, along with Normal liver. The study is performed with 111 real ultrasound images comprising of 65 typical and 46 atypical images, which were taken from 88 subjects. These images are first enhanced and then regions of interest are segmented into 800 non-overlapping segmented regions-of-interest. Subsequently 208-texture based features are extracted from each segmented region-of-interest. A two step neural network classifier is designed for classification of five liver image categories. In the first step, a... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700673 Mon, 21 Feb 2011 00:00:00 +0100 4700673 http://www.medworm.com/index.php?rid=5199094&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100019X%2Fabstract%3Frss%3Dyes Abstract: Computer-aided prognosis (CAP) is a new and exciting complement to the field of computer-aided diagnosis (CAD) and involves developing and applying computerized image analysis and multi-modal data fusion algorithms to digitized patient data (e.g. imaging, tissue, genomic) for helping physicians predict disease outcome and patient survival. While a number of data channels, ranging from the macro (e.g. MRI) to the nano-scales (proteins, genes) are now being routinely acquired for disease characterization, one of the challenges in predicting patient outcome and treatment response has been in our inability to quantitatively fuse these disparate, heterogeneous data sources. At the Laboratory for Computational Imaging and Bioinformatics (LCIB) at Rutgers University, our team has been d... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199094 Fri, 18 Feb 2011 00:00:00 +0100 5199094 http://www.medworm.com/index.php?rid=4700671&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000073%2Fabstract%3Frss%3Dyes Abstract: This paper presents a class of image reconstruction algorithms based on Amari’s α-divergence for position emission tomography. The α-divergence is actually a family of divergences indexed by α∈(−∞, +∞) that can measure discrepancy between two distributions. We consider it to model the discrepancy between projections and their estimates. By iteratively minimizing the α-divergence, a multiplicative updating algorithm is derived using an auxiliary function. The well-known ML-EM algorithm and the SA-WLS algorithm suggested by Zhu et al. arise as two special cases of our method. We prove the monotonic convergence of the algorithm, which Zhu et al. has not provided. The experiments were performed on both simulated and clinical data to study the interesting and useful beha... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700671 Fri, 18 Feb 2011 00:00:00 +0100 4700671 http://www.medworm.com/index.php?rid=4700675&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000048%2Fabstract%3Frss%3Dyes Abstract: This paper proposes image processing algorithms to recognize five types of white blood cells in peripheral blood automatically. First, a method based on Gram–Schmidt orthogonalization is proposed along with a snake algorithm to segment nucleus and cytoplasm of the cells. Then, a variety of features are extracted from the segmented regions. Next, most discriminative features are selected using a Sequential Forward Selection (SFS) algorithm and performances of two classifiers, Artificial Neural Network (ANN) and Support Vector Machine (SVM), are compared. The results demonstrate that the proposed methods are accurate and sufficiently fast to be used in hematological laboratories. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4700675 Tue, 08 Feb 2011 00:00:00 +0100 4700675 http://www.medworm.com/index.php?rid=4857640&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611111000036%2Fabstract%3Frss%3Dyes Abstract: In dynamic positron emission tomography data many researchers have attempted to exploit kinetic models within reconstruction such that parametric images are estimated directly from measurements. This work studies a direct parametric maximum likelihood expectation maximization algorithm applied to [18F]DOPA data using reference-tissue input function. We use a modified version for direct reconstruction with a gradually descending scheme of subsets (i.e. 18-6-1) initialized with the FBP parametric image for faster convergence and higher accuracy. The results compared with analytic reconstructions show quantitative robustness (i.e. minimal bias) and clinical reproducibility within six human acquisitions in the region of clinical interest. Bland–Altman plots for all the studies show... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857640 Fri, 04 Feb 2011 00:00:00 +0100 4857640 http://www.medworm.com/index.php?rid=4857641&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111100005X%2Fabstract%3Frss%3Dyes The objective of this study was to use a mixture of Poisson (MOP) model expectation maximum (EM) algorithm for segmenting microPET images. Simulated rat phantoms with partial volume effect and different noise levels were generated to evaluate the performance of the method. The partial volume correction was performed using an EM deblurring method before the segmentation. The EM–MOP outperforms the EM–MOP in terms of the estimated spatial accuracy, quantitative accuracy, robustness and computing efficiency. To conclude, the proposed EM–MOP method is a reliable and accurate approach for estimating uptake levels and spatial distributions across target tissues in microPET 11C-raclopride imaging studies. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857641 Thu, 03 Feb 2011 00:00:00 +0100 4857641 http://www.medworm.com/index.php?rid=5199104&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001369%2Fabstract%3Frss%3Dyes We present a tile-based approach for producing clinically relevant probability maps of prostatic carcinoma in histological sections from radical prostatectomy. Our methodology incorporates ensemble learning for feature selection and classification on expert-annotated images. Random forest feature selection performed over varying training sets provides a subset of generalized CIEL*a*b* co-occurrence texture features, while sample selection strategies with minimal constraints reduce training data requirements to achieve reliable results. Ensembles of classifiers are built using expert-annotated tiles from training images, and scores for the probability of cancer presence are calculated from the responses of each classifier in the ensemble. Spatial filtering of tile-based texture features pri... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199104 Thu, 27 Jan 2011 00:00:00 +0100 5199104 http://www.medworm.com/index.php?rid=5199099&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001345%2Fabstract%3Frss%3Dyes We present an iterative method to automatically determine slice correspondence between images from histology and MRI via a group-wise comparison scheme, followed by 2D and 3D registration. The image slice correspondences obtained using our method were compared with the ground truth correspondences determined via consensus of multiple experts over a total of 23 patient studies. In most instances, the results of our method were very close to the results obtained via visual inspection by these experts. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199099 Mon, 24 Jan 2011 00:00:00 +0100 5199099 http://www.medworm.com/index.php?rid=4857638&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001321%2Fabstract%3Frss%3Dyes Abstract: A modified possibilistic fuzzy c-means clustering algorithm is presented for fuzzy segmentation of magnetic resonance (MR) images that have been corrupted by intensity inhomogeneities and noise. By introducing a novel adaptive method to compute the weights of local spatial in the objective function, the new adaptive fuzzy clustering algorithm is capable of utilizing local contextual information to impose local spatial continuity, thus allowing the suppression of noise and helping to resolve classification ambiguity. To estimate the intensity inhomogeneity, the global intensity is introduced into the coherent local intensity clustering algorithm and takes the local and global intensity information into account. The segmentation target therefore is driven by two forces to smooth th... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857638 Mon, 24 Jan 2011 00:00:00 +0100 4857638 http://www.medworm.com/index.php?rid=5199093&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001357%2Fabstract%3Frss%3Dyes Abstract: Whole slide imaging/images (WSI) offers promising new perspectives for digital pathology. We launched an initiative in the anatomic pathology (AP) domain of integrating the healthcare enterprise (IHE) to define standards-based informatics transactions for integrating AP information and WSI. The IHE integration and content profiles developed as a result of this initiative successfully support the basic image acquisition and reporting processes in AP laboratories and provide a standard solution for sharing or exchanging structured AP reports in which observations can be explicitly bound to WSI or to regions of interest (ROI) in images. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199093 Tue, 18 Jan 2011 00:00:00 +0100 5199093 http://www.medworm.com/index.php?rid=4857635&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001333%2Fabstract%3Frss%3Dyes Abstract: A method for quantitatively estimating global displacement fields of coronary arterial vessel skeletons during cardiac cycles from X-ray coronary angiographic (CAG) image sequences is proposed. First, dynamic sequence of arterial lumen skeletons is semi-automatically reconstructed from a pair of angiographic image sequences acquired from two nearly orthogonal view angles covering one or several cardiac cycles. Then, displacement fields of 3D vessel skeletons at different cardiac phases are quantitatively estimated through searching optimal correspondences between skeletons of a same vessel branch at different time-points of image sequences with dynamic programming algorithm. The main advantage of this method is that possible errors introduced by calibration parameters of the imag... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857635 Wed, 12 Jan 2011 00:00:00 +0100 4857635 http://www.medworm.com/index.php?rid=4857639&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000128X%2Fabstract%3Frss%3Dyes Abstract: The expectation maximization algorithm is commonly used to reconstruct images obtained from positron emission tomography sinograms. For images with acceptable signal to noise ratios, iterations are terminated prior to convergence. A new quantitative and reproducible stopping rule is designed and validated on simulations using a Monte-Carlo generated transition matrix with a Poisson noise distribution on the sinogram data. Iterations are terminated at the solution which yields the most probable estimate of the emission densities while matching the sinogram data. It is more computationally efficient and more accurate than the standard stopping rule based on the Pearson's χ2 test. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857639 Mon, 03 Jan 2011 00:00:00 +0100 4857639 http://www.medworm.com/index.php?rid=4408445&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001278%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408445 Sat, 01 Jan 2011 00:00:00 +0100 4408445 http://www.medworm.com/index.php?rid=4408437&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001199%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408437 Sat, 01 Jan 2011 00:00:00 +0100 4408437 http://www.medworm.com/index.php?rid=4857634&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001291%2Fabstract%3Frss%3Dyes This study validated shape correspondence as a method to precisely and predictably quantify 3D condylar resorption. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857634 Mon, 27 Dec 2010 00:00:00 +0100 4857634 http://www.medworm.com/index.php?rid=4857637&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001308%2Fabstract%3Frss%3Dyes Abstract: Due to the scan time limitation, our MRI studies of the human tongue can acquire only a limited number of contiguous two-dimensional (2D) slices to form a volumetric data set in a given series. An interpolated three-dimensional (3D) reconstruction using images acquired in a single plane presents artifacts. To address this issue, we developed a wavelet-based bidirectional linear fusion method that uses slices acquired from sagittal and coronal planes to estimate the unknown values of the inter-slice voxels. We use an interpolation method to estimate the voxel value based on neighboring fiducial voxels in the bounding slices. This interpolation is followed by a wavelet fusion to recover image details by integrating prominent coefficients from the interpolated images. Our method was... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857637 Wed, 22 Dec 2010 00:00:00 +0100 4857637 http://www.medworm.com/index.php?rid=5199100&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001175%2Fabstract%3Frss%3Dyes Abstract: Histopathological examination is a powerful standard for the prognosis of critical diseases. But, despite significant advances in high-speed and high-resolution scanning devices or in virtual exploration capabilities, the clinical analysis of whole slide images (WSI) largely remains the work of human experts. We propose an innovative platform in which multi-scale computer vision algorithms perform fast analysis of a histopathological WSI. It relies on application-driven for high-resolution and generic for low-resolution image analysis algorithms embedded in a multi-scale framework to rapidly identify the high power fields of interest used by the pathologist to assess a global grading. GPU technologies as well speed up the global time-efficiency of the system. Sparse coding and dy... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=5199100 Mon, 13 Dec 2010 00:00:00 +0100 5199100 http://www.medworm.com/index.php?rid=4586110&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001151%2Fabstract%3Frss%3Dyes Abstract: This paper presents the design and construction of a 3D digital neonatal neurocranial phantom and its application for the simulation of brain magnetic resonance (MR) images. Commonly used digital brain phantoms (e.g. BrainWeb) are based on the adult brain. With the growing interest in computer-aided methods for neonatal MR image processing, there is a growing demand a digital phantom and brain MR image simulator especially for the neonatal brains. This is due to the pronounced differences between adult and neonatal brains not only in terms of size but also, more importantly, in terms of geometrical proportions and the need to subdivide white matter into two different tissue types in neonates. Therefore the neonatal brain phantom created in the here presented work consists of 9 di... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586110 Mon, 13 Dec 2010 00:00:00 +0100 4586110 http://www.medworm.com/index.php?rid=4857636&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001163%2Fabstract%3Frss%3Dyes Abstract: The illustrations in biomedical publications often provide useful information in aiding clinicians’ decisions when full text searching is performed to find evidence in support of a clinical decision. In this research, image analysis and classification techniques are explored to automatically extract information for differentiating specific modalities to characterize illustrations in biomedical publications, which may assist in the evidence finding process.Global, histogram-based, and texture image illustration features were compared to basis function luminance histogram correlation features for modality-based discrimination over a set of 742 manually annotated images by modality (radiological, photo, etc.) selected from the 2004–2005 issues of the British Journal of Oral and ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4857636 Thu, 09 Dec 2010 00:00:00 +0100 4857636 http://www.medworm.com/index.php?rid=4586107&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001102%2Fabstract%3Frss%3Dyes We present an efficient algorithm that accurately delineates the morphological surface of the cerebral cortex in real time during generation of the surface using information from parcellated 3D data. With this accurate region delineation, we then develop methods for boundary-preserved simplification and smoothing, as well as procedures for the automated correction of small, misclassified regions to improve the quality of the delineated surface. We demonstrate that our delineation algorithm, together with a new method for double-snapshot visualization of cortical regions, can be used to establish a clear correspondence between brain anatomy and mapped quantities, such as morphological measures, across groups of subjects. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586107 Thu, 09 Dec 2010 00:00:00 +0100 4586107 http://www.medworm.com/index.php?rid=4586109&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001126%2Fabstract%3Frss%3Dyes Abstract: In this paper, a method is described to automatically estimate the visible body region of a computed tomography (CT) volume image. In order to quantify the body region, a body coordinate (BC) axis is used that runs in longitudinal direction. Its origin and unit length are patient-specific and depend on anatomical landmarks. The body region of a test volume is estimated by registering it only along the longitudinal axis to a set of reference CT volume images with known body coordinates. During these 1D registrations, an axial image slice of the test volume is compared to an axial slice of a reference volume by extracting a descriptor from both slices and measuring the similarity of the descriptors. A slice descriptor consists of histograms of visual words. Visual words are code wo... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586109 Mon, 06 Dec 2010 00:00:00 +0100 4586109 http://www.medworm.com/index.php?rid=4586108&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001114%2Fabstract%3Frss%3Dyes Conclusions: This system differentiates benign from malignant breast tumors with a good result and is therefore clinically useful to provide a second opinion. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586108 Mon, 06 Dec 2010 00:00:00 +0100 4586108 http://www.medworm.com/index.php?rid=4586106&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001072%2Fabstract%3Frss%3Dyes Abstract: We developed multi-scale, live-time interactive visualization of color image data, including microscopic whole-mouse cryo-images serving many biomedical applications. Using true-color volume rendering, we interactively, selectively enhanced anatomy using feature detection. For example, to enhance red organs (vessels, liver, etc.) and internal surfaces, we computed a red feature from R/(R+G+B) and surface features from color/gray-scale gradients, respectively. For >70GB cryo-image volumes, we developed multi-resolution visualization, which provided low-resolution rendering of an entire mouse and zooming to organs, tissues, and cells. Fusions of fluorescence and color cryo-volumes uniquely showed biodistribution of metastatic and stem cells within an anatomical context. (Source: Co... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586106 Mon, 01 Nov 2010 00:00:00 +0100 4586106 http://www.medworm.com/index.php?rid=4586105&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001060%2Fabstract%3Frss%3Dyes Abstract: This paper investigates a novel statistical discrimination procedure to detect PTB when the gold standard requirement is taken into consideration. Archived data were used to establish two groups of patients which are the control and test group. The control group was used to develop the statistical discrimination procedure using four vectors of wavelet coefficients as feature vectors for the detection of pulmonary tuberculosis (PTB), lung cancer (LC), and normal lung (NL). This discrimination procedure was investigated using the test group where the number of sputum positive and sputum negative cases that were correctly classified as PTB cases were noted. The proposed statistical discrimination method is able to detect PTB patients and LC with high true positive fraction. The meth... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586105 Mon, 01 Nov 2010 00:00:00 +0100 4586105 http://www.medworm.com/index.php?rid=4586104&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001059%2Fabstract%3Frss%3Dyes Abstract: Among the parts of the human tongue surface, the sublingual vein is one of the most important ones which may have pathological relationship with some diseases. To analyze this information quantitatively, one primitive work is to extract sublingual veins accurately from tongue body. In this paper, a hyperspectral tongue imaging system instead of a digital camera is used to capture sublingual images. A hidden Markov model approach is presented to extract the sublingual veins from the hyperspectral sublingual images. This approach characterizes the spectral correlation and the band-to-band variability using a hidden Markov process, where the model parameters are estimated by the spectra of the pixel vectors forming the observation sequences. The proposed algorithm, the pixel-based s... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586104 Fri, 29 Oct 2010 00:00:00 +0100 4586104 http://www.medworm.com/index.php?rid=4586103&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001047%2Fabstract%3Frss%3Dyes Abstract: Diffusion tensor imaging (DTI) is an effective modality in studying the connectivity of the brain. To eliminate possible biases caused by fiber extraction approaches due to low spatial resolution of DTI and the number of fibers obtained, the fast marching (FM) algorithm based on the whole diffusion tensor information is proposed to model and study the brain connectivity network. Our observation is that the connectivity extracted from the whole tensor field would be more robust and reliable for constructing brain connectivity network using DTI data. To construct the connectivity network, in this paper, the arrival time map and the velocity map generated by the FM algorithm are combined to define the connectivity strength among different brain regions. The conventional fiber tracki... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4586103 Fri, 29 Oct 2010 00:00:00 +0100 4586103 http://www.medworm.com/index.php?rid=4092967&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000923%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092967 Sun, 24 Oct 2010 08:13:27 +0100 4092967 http://www.medworm.com/index.php?rid=4408444&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110001011%2Fabstract%3Frss%3Dyes Abstract: Tensor scale (t-scale) is a parametric representation of local structure morphology that simultaneously describes its orientation, shape and isotropic scale. At any image location, t-scale represents the largest ellipse (an ellipsoid in three dimensions) centered at that location and contained in the same homogeneous region. Here, we present an improved algorithm for t-scale computation and study its application to image interpolation. Specifically, the t-scale computation algorithm is improved by: (1) enhancing the accuracy of identifying local structure boundary and (2) combining both algebraic and geometric approaches in ellipse fitting. In the context of interpolation, a closed form solution is presented to determine the interpolation line at each image location in a gray lev... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408444 Thu, 21 Oct 2010 00:00:00 +0100 4408444 http://www.medworm.com/index.php?rid=4408442&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000893%2Fabstract%3Frss%3Dyes Abstract: Artifacts due to enhancement, reverberation, and multi-path reflection are commonly encountered in medical ultrasound imaging. These artifacts can adversely affect an automated image quantification algorithm or interfere with a physician’s assessment of a radiological image. This paper proposes a soft wavelet thresholding method to replace regions adversely affected by these artifacts with the texture due to the underlying tissue(s), which were originally obscured. Our proposed method soft thresholds the wavelet coefficients of affected regions to estimate the reflectivity values caused by these artifacts. By subtracting the estimated reflectivity values of the artifacts from the original reflectivity values, estimates of artifact reduced reflectivity values are attained. The i... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408442 Mon, 11 Oct 2010 00:00:00 +0100 4408442 http://www.medworm.com/index.php?rid=4408440&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000087X%2Fabstract%3Frss%3Dyes Abstract: In this paper, we introduce a new approach for tensor field segmentation based on the definition of mixtures of Gaussians on tensors as a statistical model. Working over the well-known Geodesic Active Regions segmentation framework, this scheme presents several interesting advantages. First, it yields a more flexible model than the use of a single Gaussian distribution, which enables the method to better adapt to the complexity of the data. Second, it can work directly on tensor-valued images or, through a parallel scheme that processes independently the intensity and the local structure tensor, on scalar textured images.Two different applications have been considered to show the suitability of the proposed method for medical imaging segmentation. First, we address DT-MRI segment... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408440 Fri, 08 Oct 2010 00:00:00 +0100 4408440 http://www.medworm.com/index.php?rid=4408441&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000881%2Fabstract%3Frss%3Dyes Abstract: In this paper, an automatic method for determining pairs of corresponding points between medical images is proposed. The method is based on the implementation of an artificial immune system (AIS). AIS is a relatively novel, population based category of algorithms, inspired by theoretical immunologic models. When used as function optimizers, AIS have the attractive property of locating the global optimum of a function as well as a large number of strong local optimum points. In this work, AIS has been applied both for the extraction of an optimal set of candidate points on the reference image and the definition of their corresponding ones on the second image. The performance of the proposed AIS algorithm is evaluated against the widely used Iterative Closest Point (ICP) algorithm ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408441 Mon, 04 Oct 2010 00:00:00 +0100 4408441 http://www.medworm.com/index.php?rid=4408443&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000090X%2Fabstract%3Frss%3Dyes Abstract: The paper presents a simple, parameter-free method to detect the optic disc in retinal images. It works efficiently for blurred and noisy images with a varying ratio OD/image size. The method works equally well on images with different characteristics which often cause standard methods to fail or require a new round of training. The proposed method has been tested on 214 infant and adult retinal images and has been compared against hand-drawn ground truths generated by experts. It displays consistently high OD detection rates without any prior training or adjustment of the parameters. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408443 Fri, 01 Oct 2010 00:00:00 +0100 4408443 http://www.medworm.com/index.php?rid=4408439&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000868%2Fabstract%3Frss%3Dyes Abstract: Cardiac studies are a good candidate for SPECT (single photon emission computed tomography) because of the large clinical demand and the need for improved image quality. But SPECT imaging suffers from poor spatial resolution and high statistical noise. A new SPECT system with slit–slat collimation arranged on an elliptical arc for cardiac imaging is proposed in this paper. Simulated emission computed tomography data are generated along an elliptical moving orbit with system configuration parameters. The iterative reconstruction techniques are used to implement the cardiac imaging of the proposed SPECT system. Image reconstruction can be done using the OS-EM algorithm from the data collected. This system is developed to improve the reconstructed image if attenuation correction a... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408439 Tue, 28 Sep 2010 00:00:00 +0100 4408439 http://www.medworm.com/index.php?rid=4408438&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000856%2Fabstract%3Frss%3Dyes Abstract: A high-sensitivity computer-aided diagnosis algorithm which can detect and quantify micro-calcifications for early-stage breast cancer is proposed in this research. The algorithm can be divided into two phases: image reconstruction and recognition on micro-calcification regions. For Phase I, the suspicious micro-calcification regions are separated from the normal tissues by wavelet layers and Renyi's information theory. The Morphology-Dilation and Majority Voting Rule are employed to reconstruct the scattered regions of suspicious micro-calcification. For Phase II, total 49 descriptors which mainly include shape inertia, compactness, eccentricity and grey-level co-occurrence matrix are introduced to define the characteristics of the suspicious micro-calcification clusters. In ord... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4408438 Tue, 28 Sep 2010 00:00:00 +0100 4408438 http://www.medworm.com/index.php?rid=4092972&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000765%2Fabstract%3Frss%3Dyes Abstract: Rank et al. have proposed an algorithm for estimating image noise variance composed of the following three steps: the noisy image is first filtered by a difference operator; a histogram of local signal variances is then computed; and, finally the noise variance is estimated from a statistical evaluation of the histogram. We have verified the accuracy of this algorithm on a CT image by indirect methods, and have shown that this method is able to estimate CT image noise variance with reasonable accuracy, regardless of whether or not the noiseless image is uniform. Further, we have proposed a simple alternative method for the last two steps of the Rank et al. method. However, one must pay attention to the fact that the estimated noise variance will be biased when the nearest two pix... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092972 Thu, 26 Aug 2010 23:00:00 +0100 4092972 http://www.medworm.com/index.php?rid=4092971&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000753%2Fabstract%3Frss%3Dyes Abstract: In this paper, we propose a H.264/AVC based compression technique adapted to coronary angiograms. H.264/AVC coder has proven to use the most advanced and accurate motion compensation process, but, at the cost of high computational complexity. On the other hand, analysis of coronary X-ray images reveals large areas containing no diagnostically important information. Our contribution is to exploit the energy characteristics in slice equal size regions to determine the regions with relevant information content, to be encoded using the H.264 coding paradigm. The others regions, are compressed using fixed block motion compensation and conventional hard-decision quantization. Experiments have shown that at the same bitrate, this procedure reduces the H.264 coder computing time of about... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092971 Wed, 25 Aug 2010 23:00:00 +0100 4092971 http://www.medworm.com/index.php?rid=4092973&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000777%2Fabstract%3Frss%3Dyes Abstract: Efficient visualization of vascular structures is essential for therapy planning and medical education. Existing techniques achieve high-quality visualization of vascular surfaces at the cost of low rendering speed and large size of resulting surface. In this paper, we present an approach for visualizing vascular structures by exploiting the local curvature information of a given surface. To handle complex topology of loop and multiple parents and/or multiple children, bidirectional adaptive sampling and modified normal calculations at joints are proposed. The proposed method has been applied to cerebral vascular trees, liver vessel trees, and aortic vessel trees. The experimental results show that it can obtain a high-quality surface visualization with fewer polygons in the appr... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092973 Sun, 22 Aug 2010 23:00:00 +0100 4092973 http://www.medworm.com/index.php?rid=3871029&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000273%2Fabstract%3Frss%3Dyes Abstract: Cystoscopy is used as a reference clinical examination in the detection and visualization of pathological bladder lesions. Evolution observation and analysis of these lesions is easier when panoramic images from internal bladder walls are used instead of video sequences. This work describes a fast and automatic mosaicing algorithm applied to cystoscopic video sequences, where perspective geometric transformations link successive image pairs. This mosaicing algorithm begins with a fast initialization of translation parameters computed by a cross-correlation of images, followed by an iterative optimization of transformation parameters. Finally, registered images are projected onto a global common coordinate system. A quantifying test protocol applied over a phantom yielded a mosaic... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871029 Tue, 17 Aug 2010 07:42:32 +0100 3871029 http://www.medworm.com/index.php?rid=3871023&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000698%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871023 Tue, 17 Aug 2010 07:42:28 +0100 3871023 http://www.medworm.com/index.php?rid=4092970&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000741%2Fabstract%3Frss%3Dyes Abstract: Given that neural networks have been widely reported in the research community of medical imaging, we provide a focused literature survey on recent neural network developments in computer-aided diagnosis, medical image segmentation and edge detection towards visual content analysis, and medical image registration for its pre-processing and post-processing, with the aims of increasing awareness of how neural networks can be applied to these areas and to provide a foundation for further research and practical development. Representative techniques and algorithms are explained in detail to provide inspiring examples illustrating: (i) how a known neural network with fixed structure and training procedure could be applied to resolve a medical imaging problem; (ii) how medical images c... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092970 Sun, 15 Aug 2010 23:00:00 +0100 4092970 http://www.medworm.com/index.php?rid=4092969&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000534%2Fabstract%3Frss%3Dyes We describe the details of the algorithm and provide a variety of example results. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092969 Sun, 25 Jul 2010 23:00:00 +0100 4092969 http://www.medworm.com/index.php?rid=3735763&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001360%2Fabstract%3Frss%3Dyes Abstract: Existing video monitoring techniques for sleep apnoea require clinicians to analyze substantial amounts of video data. Analysis of the covered human body from video is a challenging task as traditional computer vision methods such as correlation, template matching, background subtraction, contour models and related techniques for object tracking become ineffective because of the large degree of occlusion for long periods. To the authors’ best knowledge, there is no previously published method to estimate pose from persistently covered human body. This paper presents an automated monocular video monitoring approach to recover the human pose in conditions with persistently heavy obscuration, allowing for further analysis of covered human activity. In evaluation, we demonstrate th... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735763 Fri, 09 Jul 2010 06:41:30 +0100 3735763 http://www.medworm.com/index.php?rid=3735761&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001086%2Fabstract%3Frss%3Dyes Abstract: A new fuzzy algorithm for assessing white matter connectivity in the brain using diffusion-weighted magnetic resonance images is presented. The proposed method considers anatomical paths as chains of linked neighbouring voxels. Links between neighbours are assigned weights using the respective fibre orientation estimates. By checking all possible paths between any two voxels, a connectedness value is assigned, representative of the weakest link of the strongest path connecting the voxel pair. Multiple orientations within a voxel can be incorporated, thus allowing the utilization of fibre crossing information, while fibre branching is inherently considered. Under the assumption that paths connected strongly to a seed will exhibit adequate orientational coherence, fuzzy connectedne... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735761 Fri, 09 Jul 2010 06:41:30 +0100 3735761 http://www.medworm.com/index.php?rid=3735760&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561110900161X%2Fabstract%3Frss%3Dyes Abstract: Noise is one of the major problems that hinder an effective texture analysis of disease in medical images, which may cause variability in the reported diagnosis. In this paper seven texture measurement methods (two wavelet, two model and three statistical based) were applied to investigate their susceptibility to subtle noise caused by acquisition and reconstruction deficiencies in computed tomography (CT) images. Features of lung tumours were extracted from two different conventional and contrast enhanced CT image data-sets under filtered and noisy conditions. When measuring the noise in the background open-air region of the analysed CT images, noise of Gaussian and Rayleigh distributions with varying mean and variance was encountered, and Fishers’ distance was used to differe... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735760 Fri, 09 Jul 2010 06:41:29 +0100 3735760 http://www.medworm.com/index.php?rid=3735759&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001591%2Fabstract%3Frss%3Dyes Abstract: The purpose of this study is size-adapted segmentation of individual microcalcifications in mammography, based on microcalcification scale-space signature estimation, enabling robust scale selection for initialization of multiscale active contours. Segmentation accuracy was evaluated by the area overlap measure, by comparing the proposed method and two recently proposed ones to expert manual delineations. The method achieved area overlap of 0.61±0.15 outperforming statistically (p (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735759 Fri, 09 Jul 2010 06:41:29 +0100 3735759 http://www.medworm.com/index.php?rid=3735758&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001311%2Fabstract%3Frss%3Dyes Abstract: This paper presents an integrated and interactive decision support system for the automated melanoma recognition of the dermoscopic images based on image retrieval by content and multiple expert fusion. In this context, the ultimate aim is to support the decision making by retrieving and displaying the relevant past cases as well as predicting the image categories (e.g., melanoma, benign and dysplastic nevi) by combining outputs from different classifiers. However, the most challenging aspect in this domain is to detect the lesion from the healthy background skin and extract the lesion-specific local image features. A thresholding-based segmentation method is applied on the intensity images generated from two different schemes to detect the lesion. For the fusion-based image retr... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735758 Fri, 09 Jul 2010 06:41:29 +0100 3735758 http://www.medworm.com/index.php?rid=3735757&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001372%2Fabstract%3Frss%3Dyes Abstract: The screening of the small intestine has become painless and easy with wireless capsule endoscopy (WCE) that is a revolutionary, relatively non-invasive imaging technique performed by a wireless swallowable endoscopic capsule transmitting thousands of video frames per examination. The average time required for the visual inspection of a full 8-h WCE video ranges from 45 to 120min, depending on the experience of the examiner. In this paper, we propose a novel approach to WCE reading time reduction by unsupervised mining of video frames. The proposed methodology is based on a data reduction algorithm which is applied according to a novel scheme for the extraction of representative video frames from a full length WCE video. It can be used either as a video summarization or as a vide... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735757 Fri, 09 Jul 2010 06:41:29 +0100 3735757 http://www.medworm.com/index.php?rid=3735756&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001633%2Fabstract%3Frss%3Dyes Abstract: This paper describes an algorithm that forms a retinal vessel graph by analysing the potential connectivity of segmented retinal vessels. Self organizing feature maps (SOFMs) are used to model implicit cost functions for the junction geometry. The algorithm uses these cost functions to resolve the configuration of local sets of segment ends, thus determining the network connectivity. The system includes specialized algorithms to handle overlapping vessels. The algorithm is tested on junctions drawn from the public-domain DRIVE database. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735756 Fri, 09 Jul 2010 06:41:29 +0100 3735756 http://www.medworm.com/index.php?rid=3735755&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561110900158X%2Fabstract%3Frss%3Dyes We present a fully automated morphology-based technique able to perform accurate nuclear segmentations in images with heterogeneous staining and multiple tissue layers and we compare it with an alternate semi-automated method based on a well established segmentation approach, namely active contours. We discuss active contours’ limitations in the segmentation of immunohistochemical images and we demonstrate and motivate through extensive experiments the better accuracy of our fully automated approach compared to various active contours implementations. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735755 Fri, 09 Jul 2010 06:41:29 +0100 3735755 http://www.medworm.com/index.php?rid=3735754&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001323%2Fabstract%3Frss%3Dyes Abstract: The challenging problem of computational bioimage analysis receives growing attention from life sciences. Fluorescence microscopy is capable of simultaneously visualizing multiple molecules by staining with different fluorescent dyes. In the analysis of the result multichannel images, segmentation of ROIs resembles only a first step which must be followed by a second step towards the analysis of the ROI’s signals in the different channels. In this paper we present a system that combines image segmentation and information visualization principles for an integrated analysis of fluorescence micrographs of tissue samples. The analysis aims at the detection and annotation of cells of the Islets of Langerhans and the whole pancreas, which is of great importance in diabetes studies an... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735754 Fri, 09 Jul 2010 06:41:29 +0100 3735754 http://www.medworm.com/index.php?rid=3735753&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001608%2Fabstract%3Frss%3Dyes Abstract: During the last few years a quite large number of fluorescence imaging applications have been reported in the literature, as one of the most challenging problems in medical imaging is to “see” a tumor embedded in tissue, which is a turbid medium. This problem has not been fully encountered yet, due to the non-linear nature of the inverse problem. In this paper, a novel method for processing the forward solver outcomes is presented. Through this technique the comparison between the simulated and the acquired data can be performed only at the region-of-interest, minimizing time-consuming pixel-to-pixel comparison. With this modus operandi a-priori information about the initial fluorophore distribution becomes available, leading to a more feasible inverse problem solution. (Sour... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735753 Fri, 09 Jul 2010 06:41:29 +0100 3735753 http://www.medworm.com/index.php?rid=3735751&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001165%2Fabstract%3Frss%3Dyes Abstract: This paper presents a novel method for unsupervised DNA microarray gridding based on support vector machines (SVMs). Each spot is a small region on the microarray surface where chains of known DNA sequences are attached. The goal of microarray gridding is the separation of the spots into distinct cells. The positions of the spots on a DNA microarray image are first detected using image analysis operations and then a set of soft-margin linear SVM classifiers is used to estimate the optimal layout of the grid lines in the image. Each grid line is the separating line produced by one of the SVM classifiers, which maximizes the margin between two consecutive rows or columns of spots. The classifiers are trained using the spot locations as training vectors. The proposed method was eval... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735751 Fri, 09 Jul 2010 06:41:28 +0100 3735751 http://www.medworm.com/index.php?rid=3735749&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000558%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735749 Fri, 09 Jul 2010 06:41:28 +0100 3735749 http://www.medworm.com/index.php?rid=3735750&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000522%2Fabstract%3Frss%3Dyes Today, medical technology news more and more often reports on recent developments in the field of biomedical image technologies and systems able to detect the most subtle changes in the human body and prepared to provide early diagnoses and tools for efficient treatment management and planning. It is indeed a fact that medical and molecular imaging today drives advancements in healthcare technologies, leading the way towards the concept of the personalized medicine that is gaining impulse nowadays. Non-invasive (or at least minimally invasive) imaging procedures allow physicians to evaluate a patient's condition within minutes and take decisions on the proper therapy even in emergency cases, such like myocardial infarctions, etc. It is true that virtually all significant medical acts today... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735750 Thu, 24 Jun 2010 23:00:00 +0100 3735750 http://www.medworm.com/index.php?rid=4092968&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000510%2Fabstract%3Frss%3Dyes Abstract: Segmentation is a fundamental component of many medical image-processing applications, and it has long been recognized as a challenging problem. In this paper, we report our research and development efforts on analyzing and extracting clinically meaningful regions from uterine cervix images in a large database created for the study of cervical cancer. In addition to proposing new algorithms, we also focus on developing open source tools which are in synchrony with the research objectives. These efforts have resulted in three Web-accessible tools which address three important and interrelated sub-topics in medical image segmentation, respectively: the Boundary Marking Tool (BMT), Cervigram Segmentation Tool (CST), and Multi-Observer Segmentation Evaluation System (MOSES). The BMT ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=4092968 Mon, 31 May 2010 23:00:00 +0100 4092968 http://www.medworm.com/index.php?rid=3594217&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000157%2Fabstract%3Frss%3Dyes Abstract: The purpose of this study was to develop a computerized method for detection of multiple sclerosis (MS) lesions in brain magnetic resonance (MR) images. We have proposed a new false positive reduction scheme, which consisted of a rule-based method, a level set method, and a support vector machine. We applied the proposed method to 49 slices selected from 6 studies of three MS cases including 168 MS lesions. As a result, the sensitivity for detection of MS lesions was 81.5% with 2.9 false positives per slice based on a leave-one-candidate-out test, and the similarity index between MS regions determined by the proposed method and neuroradiologists was 0.768 on average. These results indicate the proposed method would be useful for assisting neuroradiologists in assessing the MS in ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594217 Tue, 25 May 2010 14:18:41 +0100 3594217 http://www.medworm.com/index.php?rid=3594216&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000145%2Fabstract%3Frss%3Dyes Abstract: Laser scanning microscopy provides high-resolution nondestructive in vivo imaging to capture specific structures that have been fluorescently labeled, such as cellular nuclei and membranes, throughout early zebrafish embryogenesis. An increasingly challenging problem biologists must face is how to effectively explore, follow, and study the thousands of cells contained in the resulting time-varying volume data that are large in space, time, and variable domain. Visual data explorations, such as direct volume rendering, have been successfully used for the analysis of volumetric data. However, visualizing large-scale time-varying fields remains a challenging problem. In this paper we present a novel Focus+Context animated volume rendering. The technique is based on the distance map ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594216 Tue, 25 May 2010 14:18:40 +0100 3594216 http://www.medworm.com/index.php?rid=3594215&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000133%2Fabstract%3Frss%3Dyes Abstract: Background: Multi-slice computed tomography (MSCT) was proved to provide precise cardiac volumetric assessment. Cardiac resynchronization therapy (CRT) is an effective treatment for selected patients with heart failure and reduced ejection fraction (HFREF). In HFREF patients we investigated the potential of MSCT based wall motion analysis in order to demonstrate CRT-induced reversed remodeling.Methods: Besides six patients with normal cardiac pump function serving as control group seven HFREF patients underwent contrast enhanced MSCT before and after CRT. Short cardiac axis views of the left ventricle (LV) in end-diastole (ED) and end-systole (ES) served for planimetry. Pre- and post-CRT MSCT based volumetry was compared with 2D echo. To demonstrate CRT-induced reverse remodeling... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594215 Tue, 25 May 2010 14:18:40 +0100 3594215 http://www.medworm.com/index.php?rid=3594214&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000121%2Fabstract%3Frss%3Dyes Abstract: In this article, we propose an automatic algorithm for coronary artery segmentation from 3D X-ray data sequences of a cardiac cycle (3D-CT scan, 64 detectors, 10 phases). This method is based on recent mathematical morphology techniques (some of them being extended in this article). It is also guided by anatomical knowledge, using discrete geometric tools to fit on the artery shape independently from any perturbation of the data. The application of the method on a validation dataset (60 images: 20 patients in 3 phases) led to 90% correct (and automatically obtained) segmentations, the 10% remaining cases corresponding to images where the SNR was very low. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594214 Tue, 25 May 2010 14:18:40 +0100 3594214 http://www.medworm.com/index.php?rid=3594213&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000029%2Fabstract%3Frss%3Dyes Abstract: It has been reported that the severity of subcortical vascular dementia (VaD) correlated with an area ratio of white matter hyperintensity (WMH) regions to the brain parenchyma (WMH area ratio). The purpose of this study was to develop a computer-aided evaluation method of WMH regions for diagnosis of subcortical VaD based on magnetic resonance (MR) images. A brain parenchymal region was segmented based on the histogram analysis of a T1-weigthed image. The WMH regions were segmented on the subtraction image between a T1-weighted and fluid-attenuated inversion-recovery (FLAIR) images using two segmentation methods, i.e., a region-growing technique and a level-set method, which were automatically and adaptively selected on each WMH region based on its image features by using a supp... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594213 Tue, 25 May 2010 14:18:40 +0100 3594213 http://www.medworm.com/index.php?rid=3594212&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001621%2Fabstract%3Frss%3Dyes Abstract: Stethoscope evaluation of the lungs is widely accepted and practiced; however, there are some widely recognized, major limitations with its use. A safe device that helped solve these limitations by translating sound into objective, quantifiable images would have clinical utility. Translating lung sounds into quantifiable images in which regional differences or asymmetry in intensities of breath sounds are presented as gradients in gray-scale is not a trivial process. Healthy lungs and lung pathology are characterized by different patterns of regional breath sound distribution and, therefore, the accuracy of mapping gray-scale images must be ensured in a controlled systematic fashion prior to clinical use of such a technique. Vibration response imaging (VRI) maps lung sounds from ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594212 Tue, 25 May 2010 14:18:40 +0100 3594212 http://www.medworm.com/index.php?rid=3594211&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001566%2Fabstract%3Frss%3Dyes Abstract: A new joint parametric and nonparametric curve evolution algorithm is proposed for medical image segmentation. In this algorithm, both the nonlinear space of level set function (nonparametric model) and the linear subspace of level set function spanned by the principle components (parametric model) are employed in the evolution procedure. The nonparametric curve evolution can drive the curve precisely to object boundaries while the parametric model acts as a statistical constraint based on the Bayesian framework in order to match object shape more robustly. As a result, our new algorithm is as robust as the parametric curve evolution algorithms and at the same time, yields more accurate segmentation results by using the shape prior information. Comparative results on segmenting v... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594211 Tue, 25 May 2010 14:18:39 +0100 3594211 http://www.medworm.com/index.php?rid=3594210&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001554%2Fabstract%3Frss%3Dyes Abstract: For many clinical SPECT studies, it is important to know not only the total activity in an organ of interest, but also the details regarding the activity distribution. In our approach, the anatomical information significantly contributes to improve reconstructed images through CT-based attenuation, scatter, and voxelized partial volume effect corrections. Our method uses the low dose CT image of each particular organ or object (e.g., tumor) to create an object-specific numeric template. Assuming that the sequential projection and reconstruction of this template result in a similar deterioration as in the real image, the template information is being used to correct this image on a voxel-by-voxel basis. In our phantom experiments using clinical camera and protocols, we recovered t... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594210 Tue, 25 May 2010 14:18:39 +0100 3594210 http://www.medworm.com/index.php?rid=3594209&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001542%2Fabstract%3Frss%3Dyes Abstract: X-ray coronary angiography (CAG) is one of widely used imaging modalities for diagnosis and interventional treatment of cardiovascular diseases. Dynamic CAG sequences acquired from several viewpoints record coronary arterial morphological information as well as dynamic performances. The aim of this work is to propose a semi-automatic method for sequentially reconstructing coronary arterial skeletons from a pair of CAG sequences covering one or several cardiac cycles acquired from different views based on snake model. The snake curve deforms directly in 3D through minimizing a predefined energy function and ultimately stops at the global optimum with the minimal energy, which is the desired 3D vessel skeleton. The energy function combines intrinsic properties of the curve and acqu... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594209 Tue, 25 May 2010 14:18:39 +0100 3594209 http://www.medworm.com/index.php?rid=3594208&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000443%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3594208 Tue, 25 May 2010 14:18:39 +0100 3594208 http://www.medworm.com/index.php?rid=3735752&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000042X%2Fabstract%3Frss%3Dyes Abstract: Due to photo-toxicity, fluorescence microscopy imaging is a trade-off between signal to noise ratio, total observation time and spatio-temporal resolution. We propose a new and simple method to quantify the signal-dependent and the non-signal-dependent components of the noise from a single fluorescence microscopy image. No reference image is required and the computation time allows on line quantification of the noise. The estimation is realized in two steps. We first estimate the signal-dependent noise by fitting the intensity of an estimated noise free image, computed by median filtering, to the estimated global noise variance. The second step estimates the signal-independent noise as the background variance, by computing the variance of the most homogeneous sub blocks of the im... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735752 Wed, 12 May 2010 23:00:00 +0100 3735752 http://www.medworm.com/index.php?rid=3871024&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000418%2Fabstract%3Frss%3Dyes Abstract: An automated lung nodule detection system can help spot lung abnormalities in CT lung images. Lung nodule detection can be achieved using template-based, segmentation-based, and classification-based methods. The existing systems that include a classification component in their structures have demonstrated better performances than their counterparts. Ensemble learners combine decisions of multiple classifiers to form an integrated output. To improve the performance of automated lung nodule detection, an ensemble classification aided by clustering (CAC) method is proposed. The method takes advantage of the random forest algorithm and offers a structure for a hybrid random forest based lung nodule classification aided by clustering. Several experiments are carried out involving the ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871024 Thu, 29 Apr 2010 23:00:00 +0100 3871024 http://www.medworm.com/index.php?rid=3871027&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000388%2Fabstract%3Frss%3Dyes Abstract: Physicians evaluate computed tomography (CT) of the brain to quantitatively and qualitatively identify various types of intracranial hematomas for patients with neurological emergencies. We propose a novel method that can perform this task in a totally automatic fashion, based on a multiresolution binary level set method. The skull regions are segmented in downsized images generated with a maximum filter. The intracranial regions are located using the average gray levels and connectivity. These regions compose the regions of interest (ROIs) for segmenting the hematoma from the normal brain. The gray levels of the voxels within these ROIs are generated with an averaging filter in a multiresolution fashion. After identifying the candidate hematoma voxels using adaptive thresholds a... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871027 Sun, 25 Apr 2010 23:00:00 +0100 3871027 http://www.medworm.com/index.php?rid=3871025&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000406%2Fabstract%3Frss%3Dyes This article illustrates a new method to align and merge two partially overlapping volumes each of them generated by cone beam computed tomography (CBCT). The aggregate volume covers a larger area of investigation and is determined by localizing one fixed LEGO brick in both of the primal volumes. Based on the LEGO brick an approximate registration of the volumes is determined. Afterwards we improve the transformation by minimizing the difference in overlapping space. In this paper we present a method which automates these two steps and provides an aligned volume. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871025 Sun, 25 Apr 2010 23:00:00 +0100 3871025 http://www.medworm.com/index.php?rid=3496525&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001414%2Fabstract%3Frss%3Dyes Abstract: 3D shape context is a method to define matching points between similar shapes. It can be used as a pre-processing step in a non-rigid registration. The main limitation of the method is point mismatching, which includes long geodesic distance mismatch causing wrong topological structure, and neighbors crossing mismatch between two adjacent points. In this paper, we propose a topological structure verification method to correct the long geodesic distance mismatch and a correspondence field smoothing method to correct the neighbors crossing mismatch. A robust 3D shape context model is generated and further combined with thin-plate spline model for non-rigid registration. The method was tested on phantoms and applied to rat hind limb and mouse hind limb skeletons registration from mi... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496525 Fri, 23 Apr 2010 14:37:30 +0100 3496525 http://www.medworm.com/index.php?rid=3496524&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001402%2Fabstract%3Frss%3Dyes Abstract: We propose an automatic hybrid image segmentation model that integrates the statistical expectation maximization (EM) model and the spatial pulse coupled neural network (PCNN) for brain magnetic resonance imaging (MRI) segmentation. In addition, an adaptive mechanism is developed to fine tune the PCNN parameters. The EM model serves two functions: evaluation of the PCNN image segmentation and adaptive adjustment of the PCNN parameters for optimal segmentation.To evaluate the performance of the adaptive EM–PCNN, we use it to segment MR brain image into gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF). The performance of the adaptive EM–PCNN is compared with that of the non-adaptive EM–PCNN, EM, and Bias Corrected Fuzzy C-Means (BCFCM) algorithms. The result ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496524 Fri, 23 Apr 2010 14:37:30 +0100 3496524 http://www.medworm.com/index.php?rid=3496523&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001396%2Fabstract%3Frss%3Dyes We present a shape optimization approach to compute patient-specific models in customized prototyping applications. We design a coupled shape prior to model the transformation between a related pair of surfaces, using a nonparametric joint probability density estimation. The coupled shape prior forces with the help of application-specific data forces and smoothness forces drive a surface deformation towards a desired output surface. We demonstrate the usefulness of the method for generating customized shape models in applications of hearing aid design and pre-operative to intra-operative anatomic surface estimation. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496523 Fri, 23 Apr 2010 14:37:30 +0100 3496523 http://www.medworm.com/index.php?rid=3496522&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001384%2Fabstract%3Frss%3Dyes Abstract: A Random Walk (RW) algorithm was designed to quantify the level of diffuse heterogeneous perfusion in brain SPECT images in patients suffering from systemic brain disease or from drug-induced therapy. The goal of the present paper is to understand the behavior of the RW method on different kinds of images (extrinsic parameters) and also to understand how to choose the right parameters of the RW (intrinsic parameters) depending on the image characteristics (i.e. SPECT images).“Extrinsic parameters” are related to the image characteristics (level/size of defect and diffuse heterogeneity) and “intrinsic” parameters are related to the parameters of the method (number (Nrw) and length of walk (Lrw), temperature (T) and slowing parameter (S)). Two successive studies were conduc... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496522 Fri, 23 Apr 2010 14:37:30 +0100 3496522 http://www.medworm.com/index.php?rid=3496521&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001359%2Fabstract%3Frss%3Dyes Abstract: Accurate, simple, and quick measurement of anatomical deformities at preoperative stage is clinically important for decision making in surgery planning. The deformities include excessive torsional, angular, and curvature deformation. This paper presents computer-aided methods for automatically measuring anatomical deformities of long bones of the lower limb. A three-dimensional bone model reconstructed from CT scan data of the patient is used as input. Anatomical landmarks on femur and tibia bone models are automatically identified using geometric algorithms. Medial axes of femur and tibia bones, and anatomical landmarks are used to generate functional and reference axes. These methods have been implemented in a software program and tested on a set of CT scan data. Overall, the p... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496521 Fri, 23 Apr 2010 14:37:30 +0100 3496521 http://www.medworm.com/index.php?rid=3496520&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001347%2Fabstract%3Frss%3Dyes Abstract: This paper presents an approach for breast cancer diagnosis in digital mammogram using curvelet transform. After decomposing the mammogram images in curvelet basis, a special set of the biggest coefficients is extracted as feature vector. The Euclidean distance is then used to construct a supervised classifier. The experimental results gave a 98.59% classification accuracy rate, which indicate that curvelet transformation is a promising tool for analysis and classification of digital mammograms. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496520 Fri, 23 Apr 2010 14:37:30 +0100 3496520 http://www.medworm.com/index.php?rid=3496519&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001335%2Fabstract%3Frss%3Dyes Abstract: Magnetic resonance imaging (MRI) is a valuable instrument in medical science owing to its capabilities in soft tissue characterization and 3D visualization. A potential application of MRI in clinical practice is brain parenchyma classification. This work proposes a novel approach called “Unsupervised Linear Discriminant Analysis (ULDA)” to classify and segment the three major tissues, i.e. gray matter (GM), white matter (WM) and cerebral spinal fluid (CSF), from a multi-spectral MR image of the human brain. The ULDA comprises two processes, namely Target Generation Process (TGP) and Linear Discriminant Analysis (LDA) classification. TGP is a fuzzy-set process that generates a set of potential targets from unknown information, and applies these targets to train the optimal div... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496519 Fri, 23 Apr 2010 14:37:29 +0100 3496519 http://www.medworm.com/index.php?rid=3496518&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000303%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3496518 Fri, 23 Apr 2010 14:37:29 +0100 3496518 http://www.medworm.com/index.php?rid=3871026&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561111000039X%2Fabstract%3Frss%3Dyes Abstract: This paper addresses the problem of estimating the 3D rigid poses of a CT volume of an object from its 2D X-ray projection(s). We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measures only take intensity values into account without considering spatial information and their robustness is questionable. In this paper, instead of directly maximizing mutual information, we propose to use a variational approximation derived from the Kullback-Leibler bound. Spatial information is then incorporated into this variational approximation using a Markov random field model. The newly derived similarity measure has a least-squares form and can be effective... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871026 Thu, 22 Apr 2010 23:00:00 +0100 3871026 http://www.medworm.com/index.php?rid=3735762&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000376%2Fabstract%3Frss%3Dyes Abstract: This work presents a new method for motion estimation of tagged cardiac magnetic resonance sequences based on variational techniques. The variational method has been improved by adding a new term in the optical flow equation that incorporates tracking points with high stability of phase. Results were obtained through simulated and real data, and were validated by manual tracking and with respect to a reference state-of-the-art method: harmonic phase imaging (HARP). The error, measured in pixels per frame, obtained with the proposed variational method is one order of magnitude smaller than the one achieved by the reference method, and it requires a lower computational cost. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3735762 Wed, 21 Apr 2010 23:00:00 +0100 3735762 http://www.medworm.com/index.php?rid=3871028&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000285%2Fabstract%3Frss%3Dyes Abstract: Developing detailed lung airway models is an important step towards understanding the respiratory system. While modern imaging and airway casting approaches have dramatically improved the potential detail of such models, challenges have arisen in image processing as the demand for greater detail pushes the image processing approaches to their limits. Airway segmentations with proper topology have neither loops nor invalid voxel-to-voxel connections. Here we describe a new technique for segmenting airways with proper topology and apply the approach to an image volume generated by magnetic resonance imaging of a silicone cast created from an excised monkey lung. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3871028 Sun, 11 Apr 2010 23:00:00 +0100 3871028 http://www.medworm.com/index.php?rid=3309864&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561110900130X%2Fabstract%3Frss%3Dyes Abstract: This paper presents an automatic method for segmentation of brain structures using their symmetry and tissue type information. The proposed method generates segmented structures that have homogenous tissues. It benefits from general symmetry of the brain structures in the two hemispheres. It also benefits from the tissue regions generated by fuzzy c-means clustering. All in all, the proposed method can be described as a dynamic knowledge-based method that eliminates the need for statistical shape models of the structures while generating accurate segmentation results. The proposed approach is implemented in MATLAB and tested on the Internet Brain Segmentation Repository (IBSR) datasets. To this end, it is applied to the segmentation of caudate and ventricles three-dimensionally i... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309864 Fri, 26 Feb 2010 15:32:29 +0100 3309864 http://www.medworm.com/index.php?rid=3309863&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001293%2Fabstract%3Frss%3Dyes Abstract: The detection of exudates is a prerequisite for detecting and grading severe retinal lesions, like the diabetic macular edema. In this work, we present a new method based on mathematical morphology for detecting exudates in color eye fundus images. A preliminary evaluation of the proposed method performance on a known public database, namely DIARETDB1, indicates that it can achieve an average sensitivity of 70.48%, and an average specificity of 98.84%. Comparing to other recent automatic methods available in the literature, our proposed approach potentially can obtain better exudate detection results in terms of sensitivity and specificity. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309863 Fri, 26 Feb 2010 15:32:29 +0100 3309863 http://www.medworm.com/index.php?rid=3309862&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001177%2Fabstract%3Frss%3Dyes Abstract: In this paper an algorithm for vessel segmentation and network extraction in retinal images is proposed. A new multi-scale line-tracking procedure is starting from a small group of pixels, derived from a brightness selection rule, and terminates when a cross-sectional profile condition becomes invalid. The multi-scale image map is derived after combining the individual image maps along scales, containing the pixels confidence to belong in a vessel. The initial vessel network is derived after map quantization of the multi-scale confidence matrix. Median filtering is applied in the initial vessel network, restoring disconnected vessel lines and eliminating noisy lines. Finally, post-processing removes erroneous areas using directional attributes of vessels and morphological reconst... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309862 Fri, 26 Feb 2010 15:32:28 +0100 3309862 http://www.medworm.com/index.php?rid=3309861&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001153%2Fabstract%3Frss%3Dyes Abstract: Retinal blood vessels are important objects in ophthalmologic images. In spite of many attempts for vessel detection, it appears that existing methodologies are based on edge detection or modeling of vessel cross-sectional profiles in intensity. The application of these methodologies is hampered by the presence of a wide range of retinal vessels. In this paper we define a universal representation for upward and downward vessel cross-sectional profiles with varying boundary sharpness. This expression is used to define a new scheme of vessel detection based on symmetry and asymmetry in the Fourier domain. Phase congruency is utilized for measuring symmetry and asymmetry so that our scheme is invariant to vessel brightness variations. We have performed experiments on fluorescein ima... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309861 Fri, 26 Feb 2010 15:32:28 +0100 3309861 http://www.medworm.com/index.php?rid=3309860&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001141%2Fabstract%3Frss%3Dyes Abstract: Classifying brain white matter fibers into bundles is of growing interest in neuroscience. Quantification of diffusion characteristics inside a fiber bundle provides new insights for disease evolutions, therapy effects, and surgical interventions. In this paper, we present a novel method for segmenting fiber bundles using spherical harmonic coefficients (SHC) that describe diffusion signal obtained from High Angular Resolution Diffusion Imaging (HARDI) protocols. Based on SHC, we define a similarity measure and use it as a speed function term in level set framework. We show advantages of the proposed measure over similarity measures based on Diffusion Tensor Imaging (DTI) indices. Without any assumptions about diffusion model, we deal with diffusion signal instead of orientation ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309860 Fri, 26 Feb 2010 15:32:27 +0100 3309860 http://www.medworm.com/index.php?rid=3309859&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS089561110900113X%2Fabstract%3Frss%3Dyes Abstract: An accurate and standardized technique for breast tumor segmentation is a critical step for monitoring and quantifying breast cancer. The fully automated tumor segmentation in mammograms presents many challenges related to characteristics of an image. In this paper, a comparison of two different semi-automated methods, viz., level set and marker controlled watershed methods that perform an accurate and fast segmentation of tumor is made. The robustness of the proposed methods is demonstrated by the segmentation of a set of 17 mammogram images. Numerical validation of the results is also provided. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309859 Fri, 26 Feb 2010 15:32:27 +0100 3309859 http://www.medworm.com/index.php?rid=3309858&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001116%2Fabstract%3Frss%3Dyes Abstract: The neuroanatomical morphology of the optic nerve is an important description for understanding different aspects like topological distribution of nerves. Manual identification and morphometry has been usually considered as tedious, time consuming, and susceptible to error. A method that automates the identification and analysis of axons from electron micrographic images is presented. First, using region growing approach binarizes the image by combining the feature information together with spatial information, and obtains a coarse classification between myelin and non-myelin pixels. Next, identifies the axon candidates by region labeling and remove false axons on the basis of the identification ruler. Then the connected myelin sheaths are separated from each other using the maxi... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309858 Fri, 26 Feb 2010 15:32:27 +0100 3309858 http://www.medworm.com/index.php?rid=3309857&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000170%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3309857 Fri, 26 Feb 2010 15:32:27 +0100 3309857 http://www.medworm.com/index.php?rid=3226356&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001578%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226356 Mon, 01 Feb 2010 16:30:23 +0100 3226356 http://www.medworm.com/index.php?rid=3226355&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001104%2Fabstract%3Frss%3Dyes Abstract: A novel denoising approach is proposed that is based on a spectral data substitution mechanism through using a mathematical model of one-dimensional singularity function analysis (1-D SFA). The method consists in dividing the complete spectral domain of the noisy signal into two subsets: the preserved set where the spectral data are kept unchanged, and the substitution set where the original spectral data having lower signal-to-noise ratio (SNR) are replaced by those reconstructed using the 1-D SFA model. The preserved set containing original spectral data is determined according to the SNR of the spectrum. The singular points and singularity degrees in the 1-D SFA model are obtained through calculating finite difference of the noisy signal. The theoretical formulation and experi... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226355 Mon, 01 Feb 2010 16:30:23 +0100 3226355 http://www.medworm.com/index.php?rid=3226354&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001074%2Fabstract%3Frss%3Dyes Abstract: This paper presents a statistical method for the detection of lobar pneumonia when using digitized chest X-ray films. Each region of interest was represented by a vector of wavelet texture measures which is then multiplied by the orthogonal matrix Q2. The first two elements of the transformed vectors were shown to have a bivariate normal distribution. Misclassification probabilities were estimated using probability ellipsoids and discriminant functions. The result of this study recommends the detection of pneumonia by constructing probability ellipsoids or discriminant function using maximum energy and maximum column sum energy texture measures where misclassification probabilities were less than 0.15. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226354 Mon, 01 Feb 2010 16:30:23 +0100 3226354 http://www.medworm.com/index.php?rid=3226353&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001062%2Fabstract%3Frss%3Dyes Abstract: A method for motion compensated iterative CT reconstruction of a cardiac region-of-interest is presented. The algorithm is an ordered subset maximum likelihood approach with spherically symmetric basis functions, and it uses an ECG for gating. Since the straightforward application of iterative methods to CT data has the drawback that a field-of-view has to be reconstructed, which covers the complete volume contributing to the absorption, region-of-interest reconstruction is applied here. Despite gating, residual object motion within the reconstructed gating window leads to motion blurring in the reconstructed image. To limit this effect, motion compensation is applied. Hereto, a gated 4D reconstruction at multiple phases is generated for the region-of-interest, and a limited set ... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226353 Mon, 01 Feb 2010 16:30:22 +0100 3226353 http://www.medworm.com/index.php?rid=3226352&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000998%2Fabstract%3Frss%3Dyes Abstract: This paper proposes a state space method for limited view PET reconstruction. Due to the high-level of noise and data-incompletion, prior knowledge is required to guide PET recovery. The compartmental model is used as an evolution equation to regularize the dynamic reconstruction. The continuous–discrete Kalman filter is adopted to calculate the radioactivity value recursively. With tracer kinetic information as prior, the state space approach can obtain a better result compared with the MLEM algorithm. The identifiability of this method is proved by computer synthetic simulation and real phantom experiment on the Hamamatsu SHR-22000PET scanner. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226352 Mon, 01 Feb 2010 16:30:22 +0100 3226352 http://www.medworm.com/index.php?rid=3226351&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000913%2Fabstract%3Frss%3Dyes Abstract: An empirical stopping criterion for the 2D-maximum-likelihood expectation–maximization (MLEM) iterative image reconstruction algorithm in positron emission tomography (PET) has been proposed. We have applied the MLEM algorithm on Monte Carlo generated noise-free projection data and studied the properties of the pixel updating coefficients (PUC) in the reconstructed images. Appropriate fitting lead to an analytical expression for the parameterization of the minimum value in the PUC vector for all non-zero pixels for a given number of detected counts, which can be employed as basis for the stopping criterion proposed. These results have been validated with simulated data from real PET images. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226351 Mon, 01 Feb 2010 16:30:22 +0100 3226351 http://www.medworm.com/index.php?rid=3226350&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000883%2Fabstract%3Frss%3Dyes Abstract: Pathogenic protozoan parasites can cause human to get many diseases, such as, amoebiasis, typhoid fever and cholera, etc. Different protozoan parasites vary greatly in their structural and biochemical properties. Digital images are extensively applied to medical fields for doctors and pathologists to analyze pathological sections and further diagnose diseases. The aim of this paper is to develop protozoan parasite extraction techniques to segment protozoan parasites from microscopic images. The proposed scheme has precise segmentation ability even if the image is with poor quality or complex background. Experimental results show that the proposed scheme can gain 96.64% average correct rate, and about 0.04, 0.45 and 0.06 of the average error rates: misclassification error (ME), re... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226350 Mon, 01 Feb 2010 16:30:22 +0100 3226350 http://www.medworm.com/index.php?rid=3226349&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000871%2Fabstract%3Frss%3Dyes Abstract: Anatomically precise geometric models of human airways and arterial vessels play a critical role in the analysis of air and blood flows in human bodies. The established geometric modelling methods become invalid when the model consists of bronchioles or small vessels. This paper presents a new method for reconstructing the entire airway tree and carotid vessels from point clouds obtained from CT or MR images. A novel layer-by-layer searching algorithm has been developed to recognize branches of the airway tree and arterial vessels from the point clouds. Instead of applying uniform accuracy to all branches regardless of the number of available points, the surface patches on each branch are constructed adaptively based on the number of available elemental points, which leads to the... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226349 Mon, 01 Feb 2010 16:30:22 +0100 3226349 http://www.medworm.com/index.php?rid=3226348&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000858%2Fabstract%3Frss%3Dyes Abstract: We introduce a novel approach to specify and edit volumes of interest (VOI for short) interactively. Enhancing the capabilities of standard systems we provide tools to edit the VOI by defining a not necessarily convex polyhedral bounding object. We suggest to use low-level editing interactions for moving, inserting and deleting vertices, edges and faces of the polyhedron. The low-level operations can be used as building blocks for more complex higher order operations fitting the application demands. Flexible initialization allows the user to select within a few clicks convex VOI that in the classical clipping plane model need the specification of a large number of cutting planes. In our model it is similarly simple to select non-convex VOI. Boolean combinations allow to select no... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226348 Mon, 01 Feb 2010 16:30:22 +0100 3226348 http://www.medworm.com/index.php?rid=3226347&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611110000042%2Fabstract%3Frss%3Dyes (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3226347 Mon, 01 Feb 2010 16:30:22 +0100 3226347 http://www.medworm.com/index.php?rid=3110002&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000597%2Fabstract%3Frss%3Dyes Abstract: The cardiac physiome model has been proven to be useful for cardiac simulation, and has been more recently utilized to medical image analysis. To perform individualized analysis, structural images are necessary to provide subject-specific cardiac geometries. Although finite element methods have been extensively used for the spatial discretization of the myocardium, their complicated meshing procedures and element-based interpolation functions often result in algorithms which are either easy to implement but numerically inaccurate, or accurate but labor-intensive. In consequence, we have adopted the meshfree platform which provides element-free approximations for computational cardiology. Complicated volume meshing procedures are excluded, and no re-meshing is needed for improving... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3110002 Tue, 22 Dec 2009 15:10:31 +0100 3110002 http://www.medworm.com/index.php?rid=3110001&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109000615%2Fabstract%3Frss%3Dyes Abstract: Statistical atlases enable the individualization of atlas information for patient specific applications such as surgical planning. In this paper, a statistical atlas comprising a point distribution model defined on the vertices of a tetrahedral mesh is registered to a subject’s computed tomography scan of the human pelvis. The approach consists of a volumetric deformable registration method augmented to maintain the topology of the atlas mesh after deformation as well as incorporating the dominant three-dimensional shape modes in the atlas. Experimental results demonstrate that incorporation of the statistical shape atlas helps to stabilize the registration and improves robustness and registration accuracy. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3110001 Tue, 22 Dec 2009 15:10:31 +0100 3110001 http://www.medworm.com/index.php?rid=3110000&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001049%2Fabstract%3Frss%3Dyes In conclusion, nonlinear propagation can play an important role in shaping the energy distribution during a focused ultrasound treatment and it should not be ignored in planning. However, the current simulation methods are accurate only with relatively large F-numbers and better models need to be developed for sharply focused transducers. (Source: Computerized Medical Imaging and Graphics) Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3110000 Tue, 22 Dec 2009 15:10:31 +0100 3110000 http://www.medworm.com/index.php?rid=3109999&cid=s_35481_37_f&fid=35481&url=http%3A%2F%2Fwww.medicalimagingandgraphics.com%2Farticle%2FPIIS0895611109001037%2Fabstract%3Frss%3Dyes Abstract: A novel system for image guidance in totally endoscopic coronary artery bypass (TECAB) is presented. Key requirement is the availability of 2D–3D registration techniques that can deal with non-rigid motion and deformation. Image guidance for TECAB is mainly required before the mechanical stabilisation of the heart, when the most dominant source of misregistration is the deformation and non-rigid motion of the heart.To augment the images in the endoscope of the da Vinci robot, we have to find the transformation from the coordinate system of the preoperative imaging modality to the system of the endoscopic cameras.In a first step we build a 4D motion model of the beating heart. Intraoperatively we can use the ECG or video processing to determine the phase of the cardiac cycle, as... Computerized Medical Imaging and Graphics journals http://www.medworm.com/rss/comments.php?id=3109999 Tue, 22 Dec 2009 15:10:30 +0100 3109999