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 'Medical Physics' source. Mon, 06 Feb 2012 20:24:59 +0100 http://www.medworm.com/index.php?rid=5657875&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22298248%26dopt%3DAbstract Authors: Bahadori AA, Van Baalen M, Shavers MR, Semones EJ, Bolch WE Abstract Computational phantoms serve an important role in organ dosimetry and risk assessment performed at the National Aeronautics and Space Administration (NASA). A previous study investigated the impact on organ dose equivalents and effective doses from the use of the University of Florida hybrid adult male (UFHADM) and adult female (UFHADF) phantoms at differing height and weight percentiles versus those given by the two existing NASA phantoms, the computerized anatomical man (CAM) and female (CAF) (Bahadori et al 2011 Phys. Med. Biol. 56 1671-94). In the present study, the UFHADM and UFHADF phantoms of different body sizes were further altered to incorporate the effects of microgravity. Body self-shielding ... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5657875 Wed, 01 Feb 2012 05:00:00 +0100 5657875 http://www.medworm.com/index.php?rid=5577821&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225269%26dopt%3DAbstract Authors: Saini J, Sherman JR, Orton CG PMID: 22225269 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577821 Sun, 01 Jan 2012 05:00:00 +0100 5577821 http://www.medworm.com/index.php?rid=5577820&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225270%26dopt%3DAbstract Conclusions: The proposed solution is able to solve surface registration problems with an accuracy suitable for radiotherapy cases where external surfaces offer primary or complementary information to patient positioning. The system shows promising dynamic properties for its use in gating/tracking applications. The overall system is competitive with commonly-used surface registration technologies. Its main benefit is the usage of a cost-effective off-the-shelf technology for surface acquisition. Further strategies to improve the registration accuracy are under development. PMID: 22225270 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577820 Sun, 01 Jan 2012 05:00:00 +0100 5577820 http://www.medworm.com/index.php?rid=5577819&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225271%26dopt%3DAbstract Conclusions: Overall, the forward bias method has been found to greatly reduce detector lag ghosts in projection data and the radar artifact in CBCT reconstructions. The method is limited to improvements of the a-Si photodiode response only. A future hybrid mode may overcome any limitations of this method. PMID: 22225271 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577819 Sun, 01 Jan 2012 05:00:00 +0100 5577819 http://www.medworm.com/index.php?rid=5577818&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225272%26dopt%3DAbstract Conclusions: Our study indicates the feasibility of the 3D approach to the detection of clustered microcalcifications in DBT and that the newly designed enhancement-modulated 3D calcification response function is promising for prescreening. Further work is needed to assess the generalizability of our approach and to improve its performance. PMID: 22225272 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577818 Sun, 01 Jan 2012 05:00:00 +0100 5577818 http://www.medworm.com/index.php?rid=5577817&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225273%26dopt%3DAbstract Conclusions: The incident electron beam parameters in a Monte Carlo model of a linear accelerator could be precisely and independently determined by the benchmarking procedure proposed. As the dose distribution in the penumbra region is insensitive to moderate changes in electron energy and angular spread, accurate penumbra measurements is feasible for benchmarking the electron radial intensity distribution. This parameter is particularly important for accurate dosimetry of mlc-shaped fields and small fields. PMID: 22225273 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577817 Sun, 01 Jan 2012 05:00:00 +0100 5577817 http://www.medworm.com/index.php?rid=5577816&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225274%26dopt%3DAbstract Conclusions: This study suggested that the baseline drift of >5 mm should be avoided in the BH-IMRT. PMID: 22225274 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577816 Sun, 01 Jan 2012 05:00:00 +0100 5577816 http://www.medworm.com/index.php?rid=5577815&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225275%26dopt%3DAbstract Conclusions: Voxel-based mesh generation allows fast, automatic, and robust creation of finite element bladder models directly from binary segmentation images without user intervention. Even the low-resolution voxel-based hexahedral mesh yields comparable accuracy in bladder shape prediction and more than 20 times faster in computational speed compared to the tetrahedral mesh. This approach makes it more feasible and accessible to apply FE method to model bladder deformation in adaptive radiotherapy. PMID: 22225275 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577815 Sun, 01 Jan 2012 05:00:00 +0100 5577815 http://www.medworm.com/index.php?rid=5577814&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225276%26dopt%3DAbstract Conclusions: Regarding the performance of the minimization methods, the nonlinear CG method with NR line search yields the best convergence speed. Regarding the performance of the PICCS image reconstruction, three main conclusions can be reached. (1) The performance of PICCS is optimal when the weighting parameter of the prior image parameter is selected to be near α = 0.5. (2) The spatial resolution measured for static objects in images reconstructed using PICCS from undersampled datasets is not degraded with respect to the fully-sampled reconstruction for α near its optimal value. (3) The noise texture of PICCS reconstructions is similar to that of the prior image, which was reconstructed using the conventional FBP method. PMID: 22225276 [PubMed - as supplied by publisher] (Sou... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577814 Sun, 01 Jan 2012 05:00:00 +0100 5577814 http://www.medworm.com/index.php?rid=5577813&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225277%26dopt%3DAbstract Conclusions: 3DVH + mapcheck 2 predicts the same absolute dose, the percent of pixels failing the gamma metric, and the percent of pixels failing 2% or 3% dose difference tolerance tests as one would have obtained had one made measurements in solid water phantom using an ion chamber and coronal film instead of a diode array. This is also a necessary although not sufficient condition for validation of the accuracy of 3DVH predictions of the 3D dose using beam-by-beam measurements. PMID: 22225277 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577813 Sun, 01 Jan 2012 05:00:00 +0100 5577813 http://www.medworm.com/index.php?rid=5577812&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225278%26dopt%3DAbstract Conclusions: A prediction of the transit PDI behind a phantom or patient can be created for the purposes of treatment verification via an extension of the Van Esch through-air PDI algorithm. The results of the verification measurements through phantoms indicate that further investigation through patients during their treatments is warranted. PMID: 22225278 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577812 Sun, 01 Jan 2012 05:00:00 +0100 5577812 http://www.medworm.com/index.php?rid=5577811&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225279%26dopt%3DAbstract Conclusions: The novel ECE needle tip design outperforms the regular two-plane symmetric needle by yielding longer biopsy samples and lower insertion forces, thereby demonstrating the benefits of needle geometries that contain higher inclination angles. The use of vacuum further improves the ECE needle tip biopsy sample length and lowers insertion forces. PMID: 22225279 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577811 Sun, 01 Jan 2012 05:00:00 +0100 5577811 http://www.medworm.com/index.php?rid=5577810&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225280%26dopt%3DAbstract Conclusions: Based on the evaluated motion patterns and MV field size, the positional accuracy and system latency indicate that this system is suitable for real-time adaptive applications. PMID: 22225280 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577810 Sun, 01 Jan 2012 05:00:00 +0100 5577810 http://www.medworm.com/index.php?rid=5577809&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225281%26dopt%3DAbstract Conclusions: The first MC synchrotron photon beam model for MRT irradiations that reproduces experimental dose distributions in homogeneous media has been developed. This beam model will constitute an essential component of the TPS calculation engine for patient dose computation in forthcoming MRT clinical trials. PMID: 22225281 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577809 Sun, 01 Jan 2012 05:00:00 +0100 5577809 http://www.medworm.com/index.php?rid=5577808&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225282%26dopt%3DAbstract Conclusions: While the energy-based methods are not necessarily optimized and further improvements are likely, the linearized noise-propagation analysis provides the theoretical framework of a level playing field for optimization studies and comparison with conventional DSA. It is concluded that both dual-energy and photon-counting approaches have the potential to provide similar angiographic image quality to DSA. PMID: 22225282 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577808 Sun, 01 Jan 2012 05:00:00 +0100 5577808 http://www.medworm.com/index.php?rid=5577807&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225283%26dopt%3DAbstract Conclusions: The exit detectors in the TomoTherapy treatment systems can provide valuable information about MLC behavior during delivery. A technique to estimate the TomoTherapy binary MLC leaf open time from exit detector signals is described. This technique is shown to be both robust and accurate for delivery verification. PMID: 22225283 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577807 Sun, 01 Jan 2012 05:00:00 +0100 5577807 http://www.medworm.com/index.php?rid=5577806&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225284%26dopt%3DAbstract Conclusions: While grids improved CT number accuracy, soft-tissue CNR was reduced due to attenuation of primary radiation. CNR could be restored by increasing dose by factors of ∼1.6-2.5 depending on GR, e.g., increase from 4.6 mGy for the thorax and 12.5 mGy for the abdomen without antiscatter grids to approximately 12 mGy and 30 mGy, respectively, with a high-GR grid. However, increasing the dose poses a significant impediment to repeat intraoperative CBCT and can cause the cumulative intraoperative dose to exceed that of a single diagnostic CT scan. This places the mobile C-arm in the category of extended CBCT geometries with sufficient air gap for which the tradeoffs between CNR and dose typically do not favor incorporation of an antiscatter grid. PMID: 22225284 [PubMed - in proc... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577806 Sun, 01 Jan 2012 05:00:00 +0100 5577806 http://www.medworm.com/index.php?rid=5577805&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225285%26dopt%3DAbstract Conclusions: By using the patient's CT data, the independent dose calculation performs checks that are not performed by a measurement in a cylindrical phantom. This enables it to be used either as an additional check or to replace phantom measurements for some patients. The software has potential to be used in any application where one wishes to model changes to patient conditions. PMID: 22225285 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577805 Sun, 01 Jan 2012 05:00:00 +0100 5577805 http://www.medworm.com/index.php?rid=5577804&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225286%26dopt%3DAbstract Conclusions: Compared to curve-based or surface-based skeletons, the hybrid skeleton better matches the geometry of the data. Each rod is represented by a one-voxel-thick arc and each plate is represented by a one-voxel-thick surface. The hybrid skeleton as well as the proposed classification algorithm introduce relevant parameters linked to the presence of plates in the trabecular bone data, showing that rods and plates contain independent information about trabeculae. The hybrid skeleton offers a new opportunity for precise studies of porous media such as trabecular bone. PMID: 22225286 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577804 Sun, 01 Jan 2012 05:00:00 +0100 5577804 http://www.medworm.com/index.php?rid=5577803&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225287%26dopt%3DAbstract Conclusions: The partial volume correction method improves the quantification of PET images. The method is comparable to the GTM method but does not need MR image segmentation or prior tracer distribution information. The voxel-based method can be particularly useful for combined PET/MRI studies. PMID: 22225287 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577803 Sun, 01 Jan 2012 05:00:00 +0100 5577803 http://www.medworm.com/index.php?rid=5577802&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225288%26dopt%3DAbstract Conclusions: The authors have developed a simple and systematic approach to generate a 4D-interpolated balanced planning target volume that implicitly incorporates the dynamics of respiratory-organ motion without requiring 4D-dose computation or optimization. Preliminary results based on 4D-CT data of five previously treated lung patients showed that this new planning target approach may improve normal tissue sparing without sacrificing tumor coverage. PMID: 22225288 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577802 Sun, 01 Jan 2012 05:00:00 +0100 5577802 http://www.medworm.com/index.php?rid=5577801&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225289%26dopt%3DAbstract Conclusions: The results presented in this paper indicate that the AS model provides better accuracy than the FSPB model when calculating dose for fan beams from large radiation sources. The implementation of this model to the current treatment planning systems has the scope of advancing Co-60 based IMRT and tomotherapy. PMID: 22225289 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577801 Sun, 01 Jan 2012 05:00:00 +0100 5577801 http://www.medworm.com/index.php?rid=5577800&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225290%26dopt%3DAbstract Conclusions: TSFF demonstrated consistent reduction in CT number variations due to PSR using controlled phantom and in vivo experiments. TSFF-corrected data provided quantitative measures of perfusion (BV, MTT, and BF) with better agreement to a reference method compared to noncorrected data. Practical implementation of TSFF is expected to incur in an additional radiation exposure of 14%, when tube current is modulated to 20% of its maximum, to complete the needed full scan reconstruction. PMID: 22225290 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577800 Sun, 01 Jan 2012 05:00:00 +0100 5577800 http://www.medworm.com/index.php?rid=5577799&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225291%26dopt%3DAbstract Conclusions: These results of repair process following a reciprocal time suggest that the generalized LQ model incorporating the reciprocal time of sublethal damage repair shows a better fit than the exponential repair model. These formulas can be used to analyze the experimental and clinical data, where a slowing-down repair process appears during the course of radiation therapy. PMID: 22225291 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577799 Sun, 01 Jan 2012 05:00:00 +0100 5577799 http://www.medworm.com/index.php?rid=5577798&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225292%26dopt%3DAbstract Conclusions: Our measurements show that the dosimetric characteristics of all sectors of the LGK PFX are satisfactory. The authors recommend that the sector performance of the LGK PFX be determined initially at the time of installation of the LGK PFX and thereafter, at least annually. Similarly, our recommendation is that the total flash-radiation dose for the 16 mm collimator and the corresponding ETD value be measured on a monthly basis. Should any change in the sector movement occur, it will be revealed by the sector performance and the measurement of ETD. PMID: 22225292 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577798 Sun, 01 Jan 2012 05:00:00 +0100 5577798 http://www.medworm.com/index.php?rid=5577797&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225293%26dopt%3DAbstract Conclusions: VMAT delivery of SBRT plans optimized using biological-motivated cost-functions result in highly conformal dose distributions. Plans offer shorter treatment-time benefits and provide efficient dose delivery without compromising the plan conformity for tumors in the prostate, lung, and liver, thereby improving patient comfort and clinical throughput. The short delivery times minimize the risk of patient setup and intrafraction motion errors often associated with long SBRT treatment delivery times. PMID: 22225293 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577797 Sun, 01 Jan 2012 05:00:00 +0100 5577797 http://www.medworm.com/index.php?rid=5577796&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225294%26dopt%3DAbstract Conclusions: The authors found properly adjusting the TRUS imaging settings to lower the ultrasound gain and power effectively minimized the appearance of elevation beamwidth artifacts and in turn reduced the localization errors of the needle tip. PMID: 22225294 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577796 Sun, 01 Jan 2012 05:00:00 +0100 5577796 http://www.medworm.com/index.php?rid=5577795&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225295%26dopt%3DAbstract Conclusions: A simple analytical model for the TPR in the build-up region was developed and evaluated experimentally. The model's predicted TPR values were compared with physical measurements for irregular, square (with and without tray), rectangular, and wedged fields, for 6 and 15 MV photon beams. In every case examined, the results of the model agreed with the experimental measurements based on specific quantitative agreement criteria. The model appears useful for predicting the TPR in the build-up region of megavoltage beams for different types of fields, in different configurations. PMID: 22225295 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577795 Sun, 01 Jan 2012 05:00:00 +0100 5577795 http://www.medworm.com/index.php?rid=5577794&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225296%26dopt%3DAbstract Conclusions: None of the units assessed were found to have perfect correlation between measured and readout thickness. TMD measures and thickness readouts were different for the duplicate units from two different models/manufacturers. PMID: 22225296 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577794 Sun, 01 Jan 2012 05:00:00 +0100 5577794 http://www.medworm.com/index.php?rid=5577793&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225297%26dopt%3DAbstract Conclusions: This study shows that inverse consistency and transitivity errors in DIR have a significant dosimetric effect in dose accumulation; Depending on the image pathway taken to accumulate the dose, different results may be obtained. A postprocessing technique that reduces inverse consistency and transitivity error is presented, which allows for consistent dose accumulation regardless of the image pathway followed. PMID: 22225297 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577793 Sun, 01 Jan 2012 05:00:00 +0100 5577793 http://www.medworm.com/index.php?rid=5577792&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225298%26dopt%3DAbstract Conclusions: The results from this study suggest that RapidArc VMAT technique is dosimetrically accurate, safe, and efficient in delivering TMI within clinically acceptable time frame. PMID: 22225298 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577792 Sun, 01 Jan 2012 05:00:00 +0100 5577792 http://www.medworm.com/index.php?rid=5577791&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225299%26dopt%3DAbstract Conclusions: We did not find a consistent pattern of ventilation change as a function of radiation dose. Pretreatment ventilation was significantly lower for lobes that contained tumor, due to occlusion of the central airway. The weekly lobe ventilation data indicated that when tumor volume shrinks, ventilation increases, and when the thoracic anatomy is not visibly changed, ventilation is likely to remain unchanged. PMID: 22225299 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577791 Sun, 01 Jan 2012 05:00:00 +0100 5577791 http://www.medworm.com/index.php?rid=5577790&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225300%26dopt%3DAbstract Conclusions: This first measurement of ultrasound absorption in bone can be used to estimate the amount of heat deposition based on knowledge of the acoustic field. PMID: 22225300 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577790 Sun, 01 Jan 2012 05:00:00 +0100 5577790 http://www.medworm.com/index.php?rid=5577789&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225301%26dopt%3DAbstract Conclusions: The a-Se x-ray detector PHS responses simulated in this work include three-dimensional spatial and temporal transport of electron-hole pairs. These PHS were used to calculate the Sw. factor and compare it with experimental measurements. The Sw. factor was shown to be a function of x-ray energy and applied electric field. Trapping and recombination models are all shown to affect the Sw. factor. PMID: 22225301 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577789 Sun, 01 Jan 2012 05:00:00 +0100 5577789 http://www.medworm.com/index.php?rid=5577788&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225302%26dopt%3DAbstract Conclusions: The authors demonstrate the full MC simulations of two commercial MDCT simulators to characterize their x-ray beams. This study may be useful to establish a patient-specific dosimetry for the MDCT systems. PMID: 22225302 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577788 Sun, 01 Jan 2012 05:00:00 +0100 5577788 http://www.medworm.com/index.php?rid=5577787&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225303%26dopt%3DAbstract Conclusions: Target shape, volume, and configuration changes during radiation therapy limited the accuracy of standard rigid registration for image-guided localization in locally-advanced lung cancer. Significant error reductions were possible using other rigid registration techniques, with LE approaching the lower limit imposed by interfraction target variability throughout treatment. PMID: 22225303 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577787 Sun, 01 Jan 2012 05:00:00 +0100 5577787 http://www.medworm.com/index.php?rid=5577786&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225304%26dopt%3DAbstract Conclusions: MAPCHECK analysis demonstrates high passing rates with the stringent γ(2%/2 mm) and local normalization criteria combination. The geometry of the ARCCHECK array creates a stress test for the FFF TPS model because of the shallow depth of the entrance diodes and large air cavity. Hence, the ARCCHECK γ-analysis passing rates are lower than with the MAPCHECK, while still on par with TG-119. PMID: 22225304 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577786 Sun, 01 Jan 2012 05:00:00 +0100 5577786 http://www.medworm.com/index.php?rid=5577785&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225305%26dopt%3DAbstract Conclusions: The authors have proposed a novel groupwise registration method to achieve accurate and consistent alignment for breast DCE-MR images. In the future, the authors will further evaluate our proposed method with more clinical datasets. PMID: 22225305 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577785 Sun, 01 Jan 2012 05:00:00 +0100 5577785 http://www.medworm.com/index.php?rid=5577784&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225306%26dopt%3DAbstract Conclusions: With the in aqua vivo approach for the verification of lung cancer treatments (IMRT and VMAT), we can achieve results with the same accuracy as obtained during in vivo EPID dosimetry of sites without large inhomogeneities. PMID: 22225306 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577784 Sun, 01 Jan 2012 05:00:00 +0100 5577784 http://www.medworm.com/index.php?rid=5577783&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225307%26dopt%3DAbstract Conclusions: CARSgd showed very accurate AD(F) profiles coupled with a low computational burden and without the need for specific tuning. It can be thought of as a reference technique for carotid localization, to be used in automated intima-media thickness measurement strategies. PMID: 22225307 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577783 Sun, 01 Jan 2012 05:00:00 +0100 5577783 http://www.medworm.com/index.php?rid=5577782&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225308%26dopt%3DAbstract Conclusions: The results predict that a substantial dose boost to the nucleus of endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs in combination with brachytherapy. Such vascular dose boosts could induce tumor vascular shutdown, prompting extensive tumor cell death. PMID: 22225308 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577782 Sun, 01 Jan 2012 05:00:00 +0100 5577782 http://www.medworm.com/index.php?rid=5577781&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225309%26dopt%3DAbstract Conclusions: Electromagnetic (EM) tracking with the new WFG during C-arm based fluoroscopy guidance seems to be a step forward, and with a correction scheme implemented it should be feasible. PMID: 22225309 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577781 Sun, 01 Jan 2012 05:00:00 +0100 5577781 http://www.medworm.com/index.php?rid=5577780&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225310%26dopt%3DAbstract Conclusions: The authors have shown that a plan-class specific correction factor can be specified as a function of plan evaluation parameters especially for Farmer-type chambers. This work provides a recipe based on quantifying dose distribution to accurately select air-filled ionization chamber correction factors for nonstandard fields. PMID: 22225310 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577780 Sun, 01 Jan 2012 05:00:00 +0100 5577780 http://www.medworm.com/index.php?rid=5577779&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225311%26dopt%3DAbstract Conclusions: The Varian(®) Trilogy(®) (2300 C/D) linear accelerator including the HD120 MLC was successfully modeled and simulated using the Monte Carlo BEAMNRC code by developing an independent CM, the HDMLC CM, either in static and dynamic modes. PMID: 22225311 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577779 Sun, 01 Jan 2012 05:00:00 +0100 5577779 http://www.medworm.com/index.php?rid=5577778&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225312%26dopt%3DAbstract Conclusions: Absorption, refraction, and SAS CT imaging can be achieved using the Talbot-Lau interferometer without the additional overhead of long scan time and phase stepping. PMID: 22225312 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577778 Sun, 01 Jan 2012 05:00:00 +0100 5577778 http://www.medworm.com/index.php?rid=5577777&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225313%26dopt%3DAbstract Conclusions: Output Factors and dose profiles measurements performed, respectively, with the PSD and the PSDCA were in agreement with those obtained with the UD and EBT2 films. For stereotactic radiosurgery treatment verification, the PSD gives accurate results compared to the planning system and the IC once the latter is corrected to compensate for the averaging effect of the IC. The PSD provides precise results when used as a single detector or in a dense array, resulting in a great potential for stereotactic radiosurgery QA measurements. PMID: 22225313 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577777 Sun, 01 Jan 2012 05:00:00 +0100 5577777 http://www.medworm.com/index.php?rid=5577776&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225314%26dopt%3DAbstract Conclusions: This paper presents results from the implementation of an algorithm on a commercially available treatment planning system that quantifies the dosimetric effects of interfractional and intrafractional motion in external beam radiation therapy (EBRT) of prostate cancer. The implementation of this algorithm within a commercial treatment planning system such as Pinnacle(3) enables easy deployment in the existing clinical workflow. The results of the PDD tests validate the implementation of the DiDIT algorithm in Pinnacle(3), in comparison with previously published results. PMID: 22225314 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577776 Sun, 01 Jan 2012 05:00:00 +0100 5577776 http://www.medworm.com/index.php?rid=5577775&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225315%26dopt%3DAbstract Conclusion: Quadratic programming is an alternative approach for inverse planning which generates clinically satisfying plans in comparison to the clinical system and constitutes an efficient optimization process characterized by uniqueness and reproducibility of the solution. PMID: 22225315 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577775 Sun, 01 Jan 2012 05:00:00 +0100 5577775 http://www.medworm.com/index.php?rid=5577774&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225316%26dopt%3DAbstract Conclusions: The significant frequency dependence of the volumes with an increased probability of cavitation can be attributed to two factors: First, the volume encompassed by the focal region depends on the cube of the frequency. Second, the heat deposition increases with frequency. In conclusion, according to these simulations, the acoustic environment during HIFU brain therapy at 1 MHz is not conducive to a high probability of cavitation in extended regions of the brain. PMID: 22225316 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577774 Sun, 01 Jan 2012 05:00:00 +0100 5577774 http://www.medworm.com/index.php?rid=5577773&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225317%26dopt%3DAbstract Conclusions: This study demonstrated that denoising methods in the temporal-domain can effectively suppress noise in the spatial domain, and increase signal-to-noise ratio (SNR) for each image of different T(2)(∗) weights at multiple time points, resulting in multiple high-quality T(2)(∗) contrast images. PMID: 22225317 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577773 Sun, 01 Jan 2012 05:00:00 +0100 5577773 http://www.medworm.com/index.php?rid=5577772&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225318%26dopt%3DAbstract Conclusions: Results from phase contrast imaging data of canine hearts and human MRI data are also presented, which demonstrate the power of the framework. PMID: 22225318 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577772 Sun, 01 Jan 2012 05:00:00 +0100 5577772 http://www.medworm.com/index.php?rid=5577771&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225319%26dopt%3DAbstract Conclusions: This method could be implemented in TPS in order to calculate dosimetry correction factors when an experimental IMRT treatment verification with in-phantom ionization chamber is performed. The miss-response of the IC due to the nonreference conditions could be quickly corrected by this method rather than employing MC derived correction factors. This method can be considered as an alternative to the plan-class associated correction factors proposed recently as part of an IAEA work group on nonstandard field dosimetry. PMID: 22225319 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577771 Sun, 01 Jan 2012 05:00:00 +0100 5577771 http://www.medworm.com/index.php?rid=5577770&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225320%26dopt%3DAbstract Conclusions: The GateCT™ system revealed its consistency in temporal/phase tracking but had limitations in accurately tracking the absolute abdominal positions, thus suggesting its appropriateness for phase-sorting of 4DCT rather than amplitude-sorting. In contrast, the RPM™ system demonstrated stable respiratory signal tracking in all ranges and accurately both in phase and amplitude, and is a robust system to use for both phase-sorting and amplitude-sorting techniques. The impact of the observed mean-position drift in the GateCT™ system on the resulting 4DCT image quality, in amplitude-sorting, needs further investigation. PMID: 22225320 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577770 Sun, 01 Jan 2012 05:00:00 +0100 5577770 http://www.medworm.com/index.php?rid=5577769&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225321%26dopt%3DAbstract Conclusions: A robust automatic segmentation technique integrating textural and edge information for vessel lumen border extraction and strut detection in intravascular OCT images was designed and presented. The proposed algorithm may be employed for automated quantitative morphological analysis of in-stent neointimal hyperplasia. PMID: 22225321 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577769 Sun, 01 Jan 2012 05:00:00 +0100 5577769 http://www.medworm.com/index.php?rid=5577768&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225322%26dopt%3DAbstract Conclusions: We have developed a new automatic threshold and gradient strength selection algorithm by combining class uncertainty and spatial image gradient features. The performance of the method has been examined in terms of accuracy and reproducibility and the results found are better as compared to several popular automatic threshold selection methods. PMID: 22225322 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577768 Sun, 01 Jan 2012 05:00:00 +0100 5577768 http://www.medworm.com/index.php?rid=5577767&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225323%26dopt%3DAbstract Conclusions: In the whole body multimodal registration between CT and PET images, the utilization of both the transmission-PET and the emission-PET images in the registration process by emphasizing particular regions of the transmission-PET image using an emission-PET image is effective. This method holds promise for other image fusion applications where multiple (more than two) input images should be registered into a single informative image. PMID: 22225323 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577767 Sun, 01 Jan 2012 05:00:00 +0100 5577767 http://www.medworm.com/index.php?rid=5577766&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225324%26dopt%3DAbstract Conclusions: The proposed dynamic cone beam CT approach can accurately recover the actual contrast flow, and dynamic anatomic imaging can be obtained with high isotropic 3D resolution. This approach is promising for diagnosis and treatment planning of vascular diseases and strokes. PMID: 22225324 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577766 Sun, 01 Jan 2012 05:00:00 +0100 5577766 http://www.medworm.com/index.php?rid=5577765&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225325%26dopt%3DAbstract Conclusions: The methods for building the anatomically accurate, multimodality phantom were described in this work. All multimodal data are made available freely to the image processing community (http://pvabrain.inria.fr). We believe the phantom images could allow for the validation and further aid in the development of novel medical image processing techniques. PMID: 22225325 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577765 Sun, 01 Jan 2012 05:00:00 +0100 5577765 http://www.medworm.com/index.php?rid=5577764&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225326%26dopt%3DAbstract Response to "Comment on 'In-patient to isocenter KERMA ratios in CT'" [Med. Phys. 38, 5362-5369 (2010)]. Med Phys. 2012 Jan;39(1):562 Authors: Ogden K, Huda W PMID: 22225326 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577764 Sun, 01 Jan 2012 05:00:00 +0100 5577764 http://www.medworm.com/index.php?rid=5577763&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225327%26dopt%3DAbstract Erratum: "Correction to stereotactic body radiation therapy: The report from the AAPM Task Group No. 101" [Med. Phys. 37(8), 4078-4101 (2010)]. Med Phys. 2012 Jan;39(1):563 Authors: Benedict SH PMID: 22225327 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577763 Sun, 01 Jan 2012 05:00:00 +0100 5577763 http://www.medworm.com/index.php?rid=5577762&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225328%26dopt%3DAbstract Authors: Macklis RM, Conti PS, Bourland D PMID: 22225328 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577762 Sun, 01 Jan 2012 05:00:00 +0100 5577762 http://www.medworm.com/index.php?rid=5577761&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22225329%26dopt%3DAbstract Authors: Hendee W PMID: 22225329 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5577761 Sun, 01 Jan 2012 05:00:00 +0100 5577761 http://www.medworm.com/index.php?rid=5548140&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22198475%26dopt%3DAbstract Authors: Mobley DL, Liu S, Cerutti DS, Swope WC, Rice JE Abstract Hydration free energy calculations have become important tests of force fields. Alchemical free energy calculations based on molecular dynamics simulations provide a rigorous way to calculate these free energies for a particular force field, given sufficient sampling. Here, we report results of alchemical hydration free energy calculations for the set of small molecules comprising the 2011 Statistical Assessment of Modeling of Proteins and Ligands challenge. Our calculations are largely based on the Generalized Amber Force Field with several different charge models, and we achieved RMS errors in the 1.4-2.2 kcal/mol range depending on charge model, marginally higher than what we typically observed in previous studie... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5548140 Sat, 24 Dec 2011 05:00:00 +0100 5548140 http://www.medworm.com/index.php?rid=5531688&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fsites%2Fentrez%3Fcmd%3DSearch%26db%3Dpubmed%26term%3D%28%28%28Med%2520Phys%29%2520AND%2520%25222011%252F11%252F29%252017.00%2522%255BMHDA%255D%253A%25222011%252F12%252F23%252000.53%2522%255BMHDA%255D%29%29%2520NOT%2520%28%28%2520%28%28%28%2522Med%2520Phys%2522%255BTIAB%255D%2520OR%2520%28%2522med%2522%255BTIAB%255D%2520AND%2520%2522phys%2522%255BTIAB%255D%29%2520OR%2520%2522med%2520phys%2522%255BTIAB%255D%29%29%29%2520AND%2520%25220001%2522%255BEDAT%255D%253A%25222011%252F11%252F29%252017.00%2522%255BEDAT%255D%29%29 101 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: Med Phys These pubmed results were generated on 2011/12/23PubMed, a service of the National Library of Medicine, includes over 15 million citations for biomedical articles back to the 1950's. These citations are from MEDLINE and additional life science journals. PubMed includes links to many sites providing full text articles and other related resources. (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5531688 Fri, 23 Dec 2011 05:54:00 +0100 5531688 http://www.medworm.com/index.php?rid=5455094&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22088977%26dopt%3DAbstract Authors: Fabiszewska E, Jankowska K, Grabska I, Skrzyński W Abstract Exposure doses to women undergoing screening mammography examinations should be kept as low as reasonably achievable, but they should ensure high enough image quality for adequate diagnosis. The aim of this study was to estimate the radiation risk according to the 'European guidelines for quality assurance in breast cancer screening and diagnosis', fourth edition (European Commission 2006). Materials for this study were obtained from data from 250 screening mammography facilities in Poland. For every mammography facility, a standard average glandular dose for routine exposure was calculated. Furthermore, average glandular doses for individual mammography examinations obtained according to the methods proposed by... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5455094 Tue, 29 Nov 2011 22:00:39 +0100 5455094 http://www.medworm.com/index.php?rid=5455091&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22120684%26dopt%3DAbstract Authors: Fukase H Abstract The form of the anthropoid mandibular symphysis has recently been addressed in association with spatial requirements for the forming anterior teeth. To evaluate potential relationships between the symphyseal shape and teeth further, the growth patterns of the symphyseal region and the positioning of the tooth crypts were examined using CT data, comparing four primate species (modern humans, chimpanzees, Japanese monkeys, and hamadryas baboons) with varied symphyseal curvature and tooth size. First, results showed that interspecies differences in overall mandibular shape including symphyseal inclination and bicanine width are consistently expressed throughout postnatal ontogeny, although local symphyseal configurations related to the superior transverse to... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5455091 Fri, 25 Nov 2011 05:00:00 +0100 5455091 http://www.medworm.com/index.php?rid=5455092&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22101498%26dopt%3DAbstract Authors: Thomas PJ, Cowan JD Abstract We derive generalized spin models for the development of feedforward cortical architecture from a Hebbian synaptic learning rule in a two layer neural network with nonlinear weight constraints. Our model takes into account the effects of lateral interactions in visual cortex combining local excitation and long range effective inhibition. Our approach allows the principled derivation of developmental rules for low-dimensional feature maps, starting from high-dimensional synaptic learning rules. We incorporate the effects of smooth nonlinear constraints on net synaptic weight projected from units in the thalamic layer (the fan-out) and on the net synaptic weight received by units in the cortical layer (the fan-in). These constraints naturally cou... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5455092 Sat, 19 Nov 2011 05:00:00 +0100 5455092 http://www.medworm.com/index.php?rid=5455093&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094392%26dopt%3DAbstract The objectives of this study are to evaluate the effect of couch attenuation on quality assurance (QA) results and to present a couch top model for Monte Carlo (MC) dose calculation for RapidArc treatments. The IGRT couch top is modelled in Eclipse as a thin skin of higher density material with a homogeneous fill of foam of lower density and attenuation. The IGRT couch structure consists of two longitudinal sections referred to as thick and thin. The Hounsfield Unit (HU) characterization of the couch structure was determined using a cylindrical phantom by comparing ion chamber measurements with the dose predicted by the treatment planning system (TPS). The optimal set of HU for the inside of the couch and the surface shell was found to be respectively -960 and -700 HU in agreement with Van... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5455093 Fri, 18 Nov 2011 05:00:00 +0100 5455093 http://www.medworm.com/index.php?rid=5344060&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22016264%26dopt%3DAbstract In this study, we experimentally investigated the effect of air cavity size of cylindrical ionization chambers in a PMMA phantom and (60)Co γ-beam. Two different pairs of air-filled cylindrical ionization chambers were used. The chambers in each pair had identical construction and materials but different air cavity volume (diameter). A 20 MeV electron beam was utilized to determine the ratio of the mass of air in the cavity of the two chambers in each pair. This ratio of the mass of air in each pair was then used to compare the ratios of the ionizations obtained at different depths in the PMMA phantom and (60)Co γ-beam using the two pairs of chambers. The diameter of the air cavity of cylindrical ionization chambers influences both the depth at which the maximum ionization is observed an... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344060 Fri, 21 Oct 2011 04:00:00 +0100 5344060 http://www.medworm.com/index.php?rid=5344114&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992343%26dopt%3DAbstract Authors: Fullerton GD, Vanek KN, Orton CG PMID: 21992343 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344114 Sat, 01 Oct 2011 04:00:00 +0100 5344114 http://www.medworm.com/index.php?rid=5344113&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992344%26dopt%3DAbstract Conclusions: This result points out that very large errors can occur in calculating Z(eff) from the values of μ if a fixed value for x is used. The importance of this result to dual energy computed tomography is pointed out and it is concluded that the proper values for x are required to be incorporated in the inversion algorithms, for the different regimes of Z(eff). PMID: 21992344 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344113 Sat, 01 Oct 2011 04:00:00 +0100 5344113 http://www.medworm.com/index.php?rid=5344112&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992345%26dopt%3DAbstract Conclusions: Further evaluation of available systems and algorithms for dose accumulation are needed to create guidelines for the verification of the accumulated dose. PMID: 21992345 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344112 Sat, 01 Oct 2011 04:00:00 +0100 5344112 http://www.medworm.com/index.php?rid=5344111&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992346%26dopt%3DAbstract Conclusions: The motion compensation method can successfully compensate for large C-arm motion without using radio-opaque fiducial or external trackers. Considering the efficacy of the algorithm, its successful reconstruction rate and low computational burden, the algorithm is feasible for clinical use. PMID: 21992346 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344111 Sat, 01 Oct 2011 04:00:00 +0100 5344111 http://www.medworm.com/index.php?rid=5344110&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992347%26dopt%3DAbstract Conclusions: A formalism for quantification of breast structure and structure orientation is provided. The difference in power-law coefficient estimates when accounting for orientation was found to be statistically significant. Examples of statistically defined backgrounds indicate that breast structure is mimicked more closely when structure orientation is accounted for. PMID: 21992347 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344110 Sat, 01 Oct 2011 04:00:00 +0100 5344110 http://www.medworm.com/index.php?rid=5344109&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992348%26dopt%3DAbstract Conclusions: A (170)Tm source is primarily a bremsstrahlung source, with the majority of bremsstrahlung photons being generated in the source core and experiencing little attenuation in the source encapsulation. Electrons are efficiently absorbed by the gold and platinum encapsulations. However, for the stainless-steel capsule (or other lower Z encapsulations) electrons will escape. The dose from these electrons is dominant over the photon dose in the first few millimeter but is not taken into account by current standard treatment planning systems. The total energy spectrum of photons emerging from the source depends on the encapsulation composition and results in mean photon energies well above 100 keV. This is higher than the main gamma-ray energy peak at 84 keV. Based on our results, th... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344109 Sat, 01 Oct 2011 04:00:00 +0100 5344109 http://www.medworm.com/index.php?rid=5344108&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992349%26dopt%3DAbstract Conclusions: The HD120 MLC has been successfully implemented into the SMCP. Comparisons between MC calculations and measurements show very good agreement. The SMCP is now able to calculate accurate dose distributions for treatment plans using the HD120 MLC. PMID: 21992349 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344108 Sat, 01 Oct 2011 04:00:00 +0100 5344108 http://www.medworm.com/index.php?rid=5344107&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992350%26dopt%3DAbstract Conclusions: This study demonstrates that single shot MR tagging can be used to quantify tissue deformation caused by needle movement. The in-vivo tag persistence is sufficient to enable the application of the tagging sequence during MRI-guided needle interventions in patients. PMID: 21992350 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344107 Sat, 01 Oct 2011 04:00:00 +0100 5344107 http://www.medworm.com/index.php?rid=5344106&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992351%26dopt%3DAbstract Conclusions: The phantom constructed for the present study incorporates all characteristics necessary for accurate Level III intercomparison studies. Following use in an extensive Level III dosimetric comparison over a large time scale and geographic area, the phantom retained mechanical stability and did not show signs of radiation-induced degradation. PMID: 21992351 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344106 Sat, 01 Oct 2011 04:00:00 +0100 5344106 http://www.medworm.com/index.php?rid=5344105&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992352%26dopt%3DAbstract Conclusions: Intracranial scattering alone is responsible for a large dose contribution to the stem cell compartment. It is, therefore, important to minimize other contributing factors, particularly the collimator leakage, to maximally reduce dose to these critical structures. The use of collimator jaw tracking in conjunction with modern collimators can minimize this leakage. PMID: 21992352 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344105 Sat, 01 Oct 2011 04:00:00 +0100 5344105 http://www.medworm.com/index.php?rid=5344104&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992353%26dopt%3DAbstract Conclusions: Through measurement of the photoacoustic signal, the authors demonstrated that monitoring thermal dose may be a more appropriate method in HIFU treatment than monitoring temperature. PMID: 21992353 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344104 Sat, 01 Oct 2011 04:00:00 +0100 5344104 http://www.medworm.com/index.php?rid=5344103&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992354%26dopt%3DAbstract Conclusions: A high accuracy (∼2 mm) of the two-step feature based TPS registration algorithm was achievable for registering the liver organ. The discontinuous motion in the upper abdominal region was properly taken into consideration. Clinical implementation of the algorithm will find broad application in radiation therapy of liver cancer. PMID: 21992354 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344103 Sat, 01 Oct 2011 04:00:00 +0100 5344103 http://www.medworm.com/index.php?rid=5344102&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992355%26dopt%3DAbstract Authors: Thomas CR, Metz JM, Schreuder N PMID: 21992355 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344102 Sat, 01 Oct 2011 04:00:00 +0100 5344102 http://www.medworm.com/index.php?rid=5344101&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992356%26dopt%3DAbstract Conclusions: In-patient to isocenter relative KERMA values in Rando phantom can be used to estimate organ doses in similar sized adults undergoing CT examinations from easily measured air KERMA values at the isocenter (free in air). Conversion from in-patient air KERMA values to tissue dose would require the use of energy-appropriate conversion factors. PMID: 21992356 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344101 Sat, 01 Oct 2011 04:00:00 +0100 5344101 http://www.medworm.com/index.php?rid=5344100&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992357%26dopt%3DAbstract Conclusions: The difference between the boundaries generated by the proposed algorithm and the manually segmented boundary is close to the difference between repeated manual segmentations. The proposed method provides accurate plaque burden measurements, while considerably reducing the analysis time compared to manual review. PMID: 21992357 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344100 Sat, 01 Oct 2011 04:00:00 +0100 5344100 http://www.medworm.com/index.php?rid=5344099&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992358%26dopt%3DAbstract Conclusions: Of the three FD methods investigated, the variogram method is the most accurate and precise metric for identifying high modulation treatment fields. It is also more accurate and precise than the number of MUs, the average leaf gap, and the 2D MI. Although MapCHECK™ IMRT QA does a reasonable job at identifying high modulation fields, the variogram FD method provides one with the opportunity to quantitatively and accurately assess modulation and adjust overly modulated fields at the treatment planning stage before they are sent to the treatment machine for QA or patient treatment. PMID: 21992358 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344099 Sat, 01 Oct 2011 04:00:00 +0100 5344099 http://www.medworm.com/index.php?rid=5344098&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992359%26dopt%3DAbstract Conclusions: Discovery-690 shows very good PET physical performance for all the standard NEMA NU-2-2007 measurements. Furthermore, the new reconstruction algorithms available for PET data (TOF and PSF) allow further improvements of the D-690 image quality performance both qualitatively and quantitatively. PMID: 21992359 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344098 Sat, 01 Oct 2011 04:00:00 +0100 5344098 http://www.medworm.com/index.php?rid=5344097&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992360%26dopt%3DAbstract Conclusions: The iodine uptake of salivary glands is continuously reduced during the courses of therapy. The phenomenon of hyper-radiosensitivity may to some extent account for the occurrence of salivary gland hypofunction at very low radiation doses with low dose rates in (131)I therapy. On the other hand, failure to incorporate a nonuniform and preferential uptake by salivary gland ductal cells may result in underestimating the actual dose for the critical tissue. Other methods, including (124)I voxel-based dosimetry, are warranted to further investigate the (131)I-induced salivary gland toxicity. PMID: 21992360 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344097 Sat, 01 Oct 2011 04:00:00 +0100 5344097 http://www.medworm.com/index.php?rid=5344096&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992361%26dopt%3DAbstract Conclusions: The results show that circular holography is capable of forming accurate images with signal to noise levels higher than 8 dB in quasi real time. Compared to BMR reconstruction algorithms tested on datasets containing dense tissue structures, the holographic approach generated images of similar spatial accuracy with higher signal to noise ratios and an acceleration factor of one order of magnitude. PMID: 21992361 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344096 Sat, 01 Oct 2011 04:00:00 +0100 5344096 http://www.medworm.com/index.php?rid=5344095&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992362%26dopt%3DAbstract Conclusions: OSLDs and diodes with appropriate buildup caps can be used to measure dose on the surface of a patient and predict the delivered dose to depth dmax in a range of ±1.3% for 100 cGy. The buildup cap: can be fabricated from any material examined in this work, is best with wall thickness dmax, and causes a perturbation to the delivered dose of 4%-7% when the wall thickness is dmax. OSLDs and diodes with buildup caps can both give accurate measurements of delivered dose. PMID: 21992362 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344095 Sat, 01 Oct 2011 04:00:00 +0100 5344095 http://www.medworm.com/index.php?rid=5344094&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992363%26dopt%3DAbstract Conclusions: The manufacturer recommended EPOM appears to be incorrect at low electron energy (6 MeV). In addition, the perturbation factors for diodes may be greater than predicted by Monte Carlo simulations. PMID: 21992363 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344094 Sat, 01 Oct 2011 04:00:00 +0100 5344094 http://www.medworm.com/index.php?rid=5344093&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992364%26dopt%3DAbstract Conclusions: A real-time dose compensation functionality extending the existing beam tracking functionality has been implemented and verified by measurements. Measurements and simulated dose deliveries show that real-time dose compensation can substantially improve delivered dose distributions for large rotational target motion compared to beam tracking alone. PMID: 21992364 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344093 Sat, 01 Oct 2011 04:00:00 +0100 5344093 http://www.medworm.com/index.php?rid=5344092&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992365%26dopt%3DAbstract Conclusions: Autofocus-corrected, theoretically-exact cone-beam reconstruction is a viable option for reducing acquisition time in high-resolution micro-CT imaging. It also opens up the possibility of efficiently imaging long objects. PMID: 21992365 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344092 Sat, 01 Oct 2011 04:00:00 +0100 5344092 http://www.medworm.com/index.php?rid=5344091&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992366%26dopt%3DAbstract Conclusions: Gamma passing rate, even if calculated based on patient dose grids, has generally weak correlation to critical patient DVH errors. However, the PDP algorithm was shown to accurately predict the DVH impact using conventional planar QA results. Using patient-DVH-based metrics IMRT QA allows per-patient dose QA to be based on metrics that are both sensitive and specific. Further studies are now required to analyze new processes and action levels associated with DVH-based metrics to ensure effectiveness and practicality in the clinical setting. PMID: 21992366 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344091 Sat, 01 Oct 2011 04:00:00 +0100 5344091 http://www.medworm.com/index.php?rid=5344090&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992367%26dopt%3DAbstract Conclusions: The skin dose mapping program developed in this work represents a new tool that, as the RDSR becomes available through automated export or real-time streaming, can provide the interventional physician information needed to modify behavior when clinically appropriate. The program is nonproprietary and transferable, and also functions independent to the software systems already installed on the control room workstation. The next step will be clinical implementation where the workflow will be optimized along with further analysis of real-time capabilities. PMID: 21992367 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344090 Sat, 01 Oct 2011 04:00:00 +0100 5344090 http://www.medworm.com/index.php?rid=5344089&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992368%26dopt%3DAbstract Conclusions: A prototype system was developed, and preliminary phantom images were successfully acquired. MPFEX is a promising x-ray source for TBCT. Further improvement of tube output is needed in order for it to be used in clinical TBCT systems. PMID: 21992368 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344089 Sat, 01 Oct 2011 04:00:00 +0100 5344089 http://www.medworm.com/index.php?rid=5344088&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992369%26dopt%3DAbstract Conclusions: Left and right counterpart organs always receive different absorbed doses from target organs and deliver different absorbed doses to target organs. Therefore, in application of radiopharmaceuticals in which the dose to the organs plays a role, counterpart organs should be treated separately as two separate organs.© 2011 American Association of Physicists in Medicine. PMID: 21992369 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344088 Sat, 01 Oct 2011 04:00:00 +0100 5344088 http://www.medworm.com/index.php?rid=5344087&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992370%26dopt%3DAbstract Conclusions: The presented ac approach to RF heating near an implant, which mimics specific values for R, L, and C, allows for closed formulas to estimate the potential of RF energy transfer. A first reference point for worst-case determination in MR testing procedures can be obtained. Numerical approaches, necessary to determine spatially resolved heating maps, can be supported. PMID: 21992370 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344087 Sat, 01 Oct 2011 04:00:00 +0100 5344087 http://www.medworm.com/index.php?rid=5344086&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992371%26dopt%3DAbstract Conclusions: These results demonstrate accurate delineation of tumor motion trajectory can be achieved using PICCS-4DCBCT and the standard 1-min data acquisition. PMID: 21992371 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344086 Sat, 01 Oct 2011 04:00:00 +0100 5344086 http://www.medworm.com/index.php?rid=5344085&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992373%26dopt%3DAbstract Conclusions: This work describes and validates the synthetic CT theory and algorithm by comparing its results to actual scans. Synthetic CT is a powerful new tool that allows users to realistically see how protocol selection affects CT images and enables radiologists to retrospectively identify the lowest dose protocol achievable that provides diagnostic quality images on real patients. PMID: 21992373 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344085 Sat, 01 Oct 2011 04:00:00 +0100 5344085 http://www.medworm.com/index.php?rid=5344084&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992374%26dopt%3DAbstract Conclusions: The authors concluded that backscatter thickness is 6.0 cm for 6 MV and 4.0 cm for 15 MV for field size up to 10 × 10 cm when BCF = 0.998. If 4 cm backscatter thickness is used, BCF is 0.997 and 0.983 for field size of 10 × 10 and 40 × 40 cm for 6 MV, and is 0.998 and 0.990 for 10 × 10 and 40 × 40 cm for 15 MV, respectively. PMID: 21992374 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344084 Sat, 01 Oct 2011 04:00:00 +0100 5344084 http://www.medworm.com/index.php?rid=5344083&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992375%26dopt%3DAbstract Conclusions: In general, it has been shown that pretreatment classification of the quality of respiratory motion prediction is possible and that signals with high relative RMS error can be identified with great reliability. This is especially true for the wLMS algorithm, which has also been identified as the most precise and robust of the presented methods. PMID: 21992375 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344083 Sat, 01 Oct 2011 04:00:00 +0100 5344083 http://www.medworm.com/index.php?rid=5344082&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992376%26dopt%3DAbstract Conclusions: This work demonstrated that the partial derivative of the k space signal acquired from one coil with respect to one direction can be expressed as a sum of partial derivatives of signals from multiple coils with respect to the perpendicular k space direction(s). This relationship between the partial derivatives of k space signals is linear and shift-invariant in the Cartesian coordinate system. PMID: 21992376 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344082 Sat, 01 Oct 2011 04:00:00 +0100 5344082 http://www.medworm.com/index.php?rid=5344081&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992377%26dopt%3DAbstract Conclusions: The results indicate that accurate segmentation of the facial nerve and chorda tympani in pediatric scans is achievable, thus suggesting that safe drilling trajectories can also be computed automatically. PMID: 21992377 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344081 Sat, 01 Oct 2011 04:00:00 +0100 5344081 http://www.medworm.com/index.php?rid=5344080&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992378%26dopt%3DAbstract Conclusions: The authors have constructed a dynamic lesion phantom, demonstrated its ability to produce physiological kinetic curves, and provided estimations of its true kinetic curve behavior. This lesion phantom provides a tool for the quantitative evaluation of DCE-MRI protocols, which may lead to improved discrimination of breast cancer lesions. PMID: 21992378 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344080 Sat, 01 Oct 2011 04:00:00 +0100 5344080 http://www.medworm.com/index.php?rid=5344079&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992379%26dopt%3DAbstract Conclusions: A fairly comprehensive model for 3D imaging performance in cone-beam CT combines factors of quantum noise, system geometry, anatomical background, and imaging task. The analysis provided a valuable, quantitative guide to design, optimization, and technique selection for a musculoskeletal extremities imaging system under development. PMID: 21992379 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344079 Sat, 01 Oct 2011 04:00:00 +0100 5344079 http://www.medworm.com/index.php?rid=5344078&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992380%26dopt%3DAbstract Conclusions: A complete CAD system incorporating novel features is presented, and its performance with three separate classifiers is compared and analyzed. The overall performance of our CAD system equipped with any of the three classifiers is well with respect to other methods described in literature. PMID: 21992380 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344078 Sat, 01 Oct 2011 04:00:00 +0100 5344078 http://www.medworm.com/index.php?rid=5344077&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992381%26dopt%3DAbstract Conclusions: 4D-VOI reconstruction effectively reduces undersampling artifacts and resolves lung tumor motion in 4D-CBCT. The 4D-VOI reconstruction is computationally inexpensive compared with more sophisticated iterative algorithms. Compared with these algorithms, our 4D-VOI reconstruction is an attractive alternative in 4D-CBCT for reconstructing target motion without generating numerous streak artifacts. PMID: 21992381 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344077 Sat, 01 Oct 2011 04:00:00 +0100 5344077 http://www.medworm.com/index.php?rid=5344076&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992382%26dopt%3DAbstract Conclusions: The density of localized K-edge contrast agents can be estimated to within 1% error using filtered back projection without prior information. For noncontrast and localized-contrast scans, ROI images of general basis functions can be reconstructed to within a few percent error using a prior energy-integrating image. The ability to perform material decomposition for a limited ROI may facilitate energy-resolved CT with available photon-counting detectors. PMID: 21992382 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344076 Sat, 01 Oct 2011 04:00:00 +0100 5344076 http://www.medworm.com/index.php?rid=5344075&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992383%26dopt%3DAbstract Authors: Zaidi H, Guerra AD Abstract Early diagnosis and therapy increasingly operate at the cellular, molecular, or even at the genetic level. As diagnostic techniques transition from the systems to the molecular level, the role of multimodality molecular imaging becomes increasingly important. Positron emission tomography (PET) and magnetic resonance imaging (MRI) are powerful techniques for in vivo molecular imaging. The inability of PET to provide anatomical information is a major limitation of standalone PET systems. Combining PET and CT proved to be clinically relevant and successfully reduced this limitation by providing the anatomical information required for localization of metabolic abnormalities. However, this technology still lacks the excellent soft-tissue contrast pro... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344075 Sat, 01 Oct 2011 04:00:00 +0100 5344075 http://www.medworm.com/index.php?rid=5344074&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992384%26dopt%3DAbstract Conclusions: The new nonparametric estimator has sensitivity and scalability properties that make it particularly advantageous for signal detectability evaluation in phantom experiments using model observers. PMID: 21992384 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344074 Sat, 01 Oct 2011 04:00:00 +0100 5344074 http://www.medworm.com/index.php?rid=5344073&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992385%26dopt%3DAbstract Conclusions: PV distributions affect the image quality of DBT. The relative importance of the impact depends on the characteristics of the signal and the direction (perpendicular or parallel) relative to the direction of x-ray source motion. For a given number of PVs, the angular range and the distribution of the PVs affect the degree of in-plane and interplane blurring in opposite ways. The design of the scan parameters of tomosynthesis systems would require proper consideration of the characteristics of the signals of interest and the potential trade-off of the image quality of different types of signals. PMID: 21992385 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344073 Sat, 01 Oct 2011 04:00:00 +0100 5344073 http://www.medworm.com/index.php?rid=5344072&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992386%26dopt%3DAbstract Conclusions: For low-dose CT image restoration, the presented ndiNLM method is robust in preserving the spatial resolution and identifying the low-contrast structure. The authors can draw the conclusion that the presented ndiNLM algorithm may be useful for some clinical applications such as in perfusion imaging, radiotherapy, tumor surveillance, etc. PMID: 21992386 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344072 Sat, 01 Oct 2011 04:00:00 +0100 5344072 http://www.medworm.com/index.php?rid=5344071&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992387%26dopt%3DAbstract Conclusions: PET-MIP images better match CT-MIP images for this sample of four small CT-visible tumors as compared to ungated PET images, based on the metrics of volumetric overlap and relative volumes as well as visual interpretation. The PET-MIP is a way to incorporate 4D-PET imaging into the process of lung tumor contouring that is time-efficient for the radiation oncologist and involves minimal effort to implement in treatment planning software, because it requires only a single PET image beyond contouring on CT alone. PMID: 21992387 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344071 Sat, 01 Oct 2011 04:00:00 +0100 5344071 http://www.medworm.com/index.php?rid=5344070&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992388%26dopt%3DAbstract Conclusions: The computer-aided clinical tool allowed the accurate quantification of cystic, solid, and mixed renal tumors. Cancer types were classified into four categories using their shape and enhancement. Comprehensive imaging biomarkers of renal neoplasms on abdominal CT may facilitate their noninvasive classification, guide clinical management, and monitor responses to drugs or interventions. PMID: 21992388 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344070 Sat, 01 Oct 2011 04:00:00 +0100 5344070 http://www.medworm.com/index.php?rid=5344069&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992389%26dopt%3DAbstract Conclusions: Spectrophotometry and quantitative ultrasound are objective tools that assess radiation-induced tissue injury. Spectrophotometer parameters did not correlate with those of quantitative ultrasound suggesting that skin discoloration cannot be used as a marker for subcutaneous fibrosis. These tools may prove useful for the reduction of radiation morbidities and improvement of patient quality of life. PMID: 21992389 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344069 Sat, 01 Oct 2011 04:00:00 +0100 5344069 http://www.medworm.com/index.php?rid=5344068&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992390%26dopt%3DAbstract Conclusions: The authors have developed a 3D, FE breast model that can yield high spatial resolution breast deformations under uniaxial compression for imaging research purposes and demonstrated that small changes in the mechanical properties can affect images generated using the phantom. PMID: 21992390 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344068 Sat, 01 Oct 2011 04:00:00 +0100 5344068 http://www.medworm.com/index.php?rid=5344067&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992391%26dopt%3DAbstract Conclusions: The marker dye in EBT2 can be used to improve the response uniformity of the film. Depending on the film analysis method used, however, application of a marker-dye correction can improve or degrade the dose uncertainty relative to the net OD method. The uniformity of EBT2 was found to be independent of the time postexposure. PMID: 21992391 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344067 Sat, 01 Oct 2011 04:00:00 +0100 5344067 http://www.medworm.com/index.php?rid=5344066&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992392%26dopt%3DAbstract Conclusions: The gamma evaluation method was applicable to GK radiosurgery. For all test plans, planning dose distribution and film measurement met the tolerance criteria of 0.5 mm∕0.5% within the 50% isodose line which are used for marginal dose prescription. PMID: 21992392 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344066 Sat, 01 Oct 2011 04:00:00 +0100 5344066 http://www.medworm.com/index.php?rid=5344065&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992393%26dopt%3DAbstract Conclusions: Among the three Monte Carlo methods, the mMC method is a computationally prohibitive technique that is not well suited for time-domain fluorescence tomography applications. The pMC method is advantageous over the aMC method when the early gates are employed and large number of detectors is present. Alternatively, the aMC method is the method of choice when a small number of source-detector pairs are used. PMID: 21992393 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344065 Sat, 01 Oct 2011 04:00:00 +0100 5344065 http://www.medworm.com/index.php?rid=5344064&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992394%26dopt%3DAbstract Conclusions: The dose conversion factors can be used at clinical proton facilities to support beamline and patient specific dose per monitor unit calibrations performed in polystyrene phantoms. PMID: 21992394 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344064 Sat, 01 Oct 2011 04:00:00 +0100 5344064 http://www.medworm.com/index.php?rid=5344063&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992395%26dopt%3DAbstract Conclusions: An artificial neural network has been developed to convert fluence maps to corresponding dose maps. The feasibility and potential of an artificial neural network to replicate complex convolution kernels in the TPS for IMRT dose calculations have been demonstrated. PMID: 21992395 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344063 Sat, 01 Oct 2011 04:00:00 +0100 5344063 http://www.medworm.com/index.php?rid=5344062&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992396%26dopt%3DAbstract Conclusions: The simulation of imaging of the proton-irradiated volume in a patient body using target nuclear fragment reactions was feasible with the developed APB algorithm taking time dependence into account. With the use of the APB algorithm, it was suggested that a system of simulation of activity distributions that has levels of both accuracy and calculation time appropriate for clinical use can be constructed. PMID: 21992396 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344062 Sat, 01 Oct 2011 04:00:00 +0100 5344062 http://www.medworm.com/index.php?rid=5344061&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21992398%26dopt%3DAbstract Authors: Broga D PMID: 21992398 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5344061 Sat, 01 Oct 2011 04:00:00 +0100 5344061 http://www.medworm.com/index.php?rid=5174901&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865624%26dopt%3DAbstract In conclusion, we have presented thorough theoretical analysis and clinical validation of the PCA lung motion model. The feasibility of deriving the entire lung motion using a single marker has also been demonstrated on clinical data using a simulation approach. PMID: 21865624 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5174901 Tue, 30 Aug 2011 06:32:09 +0100 5174901 http://www.medworm.com/index.php?rid=5155697&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fsites%2Fentrez%3Fcmd%3DSearch%26db%3Dpubmed%26term%3D%28%28%28Med%2520Phys%29%2520AND%2520%25222011%252F08%252F19%252013.30%2522%255BMHDA%255D%253A%25222011%252F08%252F25%252003.44%2522%255BMHDA%255D%29%29%2520NOT%2520%28%28%2520%28%28%28%2522Med%2520Phys%2522%255BTIAB%255D%2520OR%2520%28%2522med%2522%255BTIAB%255D%2520AND%2520%2522phys%2522%255BTIAB%255D%29%2520OR%2520%2522med%2520phys%2522%255BTIAB%255D%29%29%29%2520AND%2520%25220001%2522%255BEDAT%255D%253A%25222011%252F08%252F19%252013.30%2522%255BEDAT%255D%29%29 117 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: Med Phys These pubmed results were generated on 2011/08/25PubMed, a service of the National Library of Medicine, includes over 15 million citations for biomedical articles back to the 1950's. These citations are from MEDLINE and additional life science journals. PubMed includes links to many sites providing full text articles and other related resources. (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=5155697 Thu, 25 Aug 2011 07:44:04 +0100 5155697 http://www.medworm.com/index.php?rid=5097442&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21813959%26dopt%3DAbstract Authors: Lewis JH, Li R, Jia X, Watkins WT, Lou Y, Song WY, Jiang SB An algorithm capable of mitigating respiratory motion blurring artifacts in cone-beam computed tomography (CBCT) lung tumor images based on the motion of the tumor during the CBCT scan is developed. The tumor motion trajectory and probability density function (PDF) are reconstructed from the acquired CBCT projection images using a recently developed algorithm Lewis et al (2010 Phys. Med. Biol. 55 2505-22). Assuming that the effects of motion blurring can be represented by convolution of the static lung (or tumor) anatomy with the motion PDF, a cost function is defined, consisting of a data fidelity term and a total variation regularization term. Deconvolution is performed through iterative minimization of this cost fu... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5097442 Tue, 02 Aug 2011 23:00:00 +0100 5097442 http://www.medworm.com/index.php?rid=5000803&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21701052%26dopt%3DAbstract Authors: Arnold A, Bruhns OT, Mosler J A novel finite element formulation suitable for computing efficiently the stiffness distribution in soft biological tissue is presented in this paper. For that purpose, the inverse problem of finite strain hyperelasticity is considered and solved iteratively. In line with Arnold et al (2010 Phys. Med. Biol. 55 2035), the computing time is effectively reduced by using adaptive finite element methods. In sharp contrast to previous approaches, the novel mesh adaption relies on an r-adaption (re-allocation of the nodes within the finite element triangulation). This method allows the detection of material interfaces between healthy and diseased tissue in a very effective manner. The evolution of the nodal positions is canonically driven by the same min... Medical Physics journals http://www.medworm.com/rss/comments.php?id=5000803 Thu, 07 Jul 2011 07:00:06 +0100 5000803 http://www.medworm.com/index.php?rid=4803873&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fsites%2Fentrez%3Fcmd%3DSearch%26db%3Dpubmed%26term%3D%28%28%28Med%2520Phys%29%2520AND%2520%25222011%252F03%252F28%252001.00%2522%255BMHDA%255D%253A%25222011%252F05%252F10%252014.00%2522%255BMHDA%255D%29%29%2520NOT%2520%28%28%2520%28%28%28%2522Med%2520Phys%2522%255BTIAB%255D%2520OR%2520%28%2522med%2522%255BTIAB%255D%2520AND%2520%2522phys%2522%255BTIAB%255D%29%2520OR%2520%2522med%2520phys%2522%255BTIAB%255D%29%29%29%2520AND%2520%25220001%2522%255BEDAT%255D%253A%25222011%252F03%252F28%252001.00%2522%255BEDAT%255D%29%29 121 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: Med Phys These pubmed results were generated on 2011/05/10PubMed, a service of the National Library of Medicine, includes over 15 million citations for biomedical articles back to the 1950's. These citations are from MEDLINE and additional life science journals. PubMed includes links to many sites providing full text articles and other related resources. (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4803873 Tue, 10 May 2011 18:00:02 +0100 4803873 http://www.medworm.com/index.php?rid=4637986&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21404236%26dopt%3DAbstract Authors: Fukase H To examine morphological interrelationships between canine size and mandibular corpus shape, inter-sex comparisons were made in the hamadryas baboon and the Japanese monkey, known to display extreme and moderate canine dimorphism, respectively. Results of adult comparisons showed that all mandibular dimensions were significantly larger in the males than in the females in both species. In the hamadryas baboon, the males also exhibited a higher ratio of anterior to posterior corpus height than the females. This sex difference in corpus shape was not significant in the Japanese monkey, indicating lack of involvement of canine dimorphism. Analysis of mandibular growth patterns in the hamadryas baboon demonstrated that significant sexual size difference did not occur befor... Medical Physics journals http://www.medworm.com/rss/comments.php?id=4637986 Mon, 28 Mar 2011 05:00:15 +0100 4637986 http://www.medworm.com/index.php?rid=4470634&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21312181%26dopt%3DAbstract In this study we report novel data on the Y-chromosome variation in the Libyan Tuareg from Al Awaynat and Tahala, two villages in Fezzan, whose maternal genetic pool was previously characterized. High-resolution investigation of 37 Y-chromosome STR loci and analysis of 35 bi-allelic markers in 47 individuals revealed a predominant northwest African component (E-M81, haplogroup E1b1b1b) which likely originated in the second half of the Holocene in the same ancestral population that contributed to the maternal pool of the Libyan Tuareg. A significant paternal contribution from south-Saharan Africa (E-U175, haplogroup E1b1a8) was also detected, which may likely be due to recent secondary introduction, possibly through slavery practices or fusion between different tribal groups. The difference... Medical Physics journals http://www.medworm.com/rss/comments.php?id=4470634 Thu, 10 Feb 2011 00:00:00 +0100 4470634 http://www.medworm.com/index.php?rid=4400200&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21248390%26dopt%3DAbstract Authors: Katsevich A The derivative at constant direction is frequently used in inversion of cone-beam data. Several algorithms for computing the derivative have been proposed in the literature. The best algorithm to date has been proposed recently by Noo et al (2007 Phys. Med. Biol. 52 5393-414). In this note we propose a new, simple and efficient formula for computing the derivative. Numerical experiments with helical CT show that our formula and the one of Noo et al provide fairly similar spatial resolution and noise stability, even though the new formula is more efficient and easier to implement. PMID: 21248390 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4400200 Thu, 20 Jan 2011 00:00:00 +0100 4400200 http://www.medworm.com/index.php?rid=4400199&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21248393%26dopt%3DAbstract Authors: Jan S, Benoit D, Becheva E, Carlier T, Cassol F, Descourt P, Frisson T, Grevillot L, Guigues L, Maigne L, Morel C, Perrot Y, Rehfeld N, Sarrut D, Schaart DR, Stute S, Pietrzyk U, Visvikis D, Zahra N, Buvat I GATE (Geant4 Application for Emission Tomography) is a Monte Carlo simulation platform developed by the OpenGATE collaboration since 2001 and first publicly released in 2004. Dedicated to the modelling of planar scintigraphy, single photon emission computed tomography (SPECT) and positron emission tomography (PET) acquisitions, this platform is widely used to assist PET and SPECT research. A recent extension of this platform, released by the OpenGATE collaboration as GATE V6, now also enables modelling of x-ray computed tomography and radiation therapy experiments. This pa... Medical Physics journals http://www.medworm.com/rss/comments.php?id=4400199 Thu, 20 Jan 2011 00:00:00 +0100 4400199 http://www.medworm.com/index.php?rid=4400198&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21251073%26dopt%3DAbstract Conclusions:  These results suggest a possible haplotype effect of VEGF polymorphisms expression in BRONJ Italian female patients. Studies with different and larger populations possibly using TagSNP to represent all haplotypes within the VEGF gene are needed to further delineate the genetic contribution of this gene to BRONJ. PMID: 21251073 [PubMed - as supplied by publisher] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4400198 Thu, 20 Jan 2011 00:00:00 +0100 4400198 http://www.medworm.com/index.php?rid=4400201&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21230748%26dopt%3DAbstract We present data on the steady-state properties of multiple interface model, which are in good agreement with theory [R. E. Johnson and S. S. Sadhal, Annu. Rev. Fluid Mech. 17, 289 (1985)10.1146/annurev.fl.17.010185.001445], specifically on the shapes of multidrop systems. Section is an analysis of the kinetic and continuum-scale descriptions of the underlying two-component lattice Boltzmann model for immiscible fluids, extendable to more than two immiscible fluids. This extension requires (i) the use of a more local kinetic equation perturbation which is (ii) free from a reliance on measured interfacial curvature. It should be noted that viewed simply as a two-component method, the continuum algorithm is inferior to our previous methods, reported by Lishchuk [Phys. Rev. E 67, 036701 (2003)... Medical Physics journals http://www.medworm.com/rss/comments.php?id=4400201 Wed, 01 Dec 2010 00:00:00 +0100 4400201 http://www.medworm.com/index.php?rid=4275741&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158267%26dopt%3DAbstract Point/counterpoint. The title "radiation oncology physicist" should be changed to "oncologic physicist". Med Phys. 2010 Nov;37(11):5565-7 Authors: Kowalsky WP, Fraser MW, Orton CG PMID: 21158267 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275741 Mon, 01 Nov 2010 00:00:00 +0100 4275741 http://www.medworm.com/index.php?rid=4275740&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158268%26dopt%3DAbstract Authors: Molloy JA Improvements in delivery techniques for total body irradiation (TBI) using Tomotherapy and intensity modulated radiation therapy have been proven feasible. Despite the promise of improved dose conformality, the application of these "sequential" techniques has been hampered by concerns over dose heterogeneity to circulating blood. The present study was conducted to provide quantitative evidence regarding the potential clinical impact of this heterogeneity. PMID: 21158268 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275740 Mon, 01 Nov 2010 00:00:00 +0100 4275740 http://www.medworm.com/index.php?rid=4275739&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158269%26dopt%3DAbstract Authors: Seguchi S, Aoyama T, Koyama S, Fujii K, Yamauchi-Kawaura C The aim of this study was to evaluate radiation dose to patients undergoing computed tomography coronary angiography (CTCA) for prospectively gated axial (PGA) technique and retrospectively gated helical (RGH) technique. PMID: 21158269 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275739 Mon, 01 Nov 2010 00:00:00 +0100 4275739 http://www.medworm.com/index.php?rid=4275736&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158270%26dopt%3DAbstract "SABER": A new software tool for radiotherapy treatment plan evaluation. Med Phys. 2010 Nov;37(11):5586-92 Authors: Zhao B, Joiner MC, Orton CG, Burmeister J Both spatial and biological information are necessary in order to perform true optimization of a treatment plan and for predicting clinical outcome. The goal of this work is to develop an enhanced treatment plan evaluation tool which incorporates biological parameters and retains spatial dose information. PMID: 21158270 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275736 Mon, 01 Nov 2010 00:00:00 +0100 4275736 http://www.medworm.com/index.php?rid=4275734&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158271%26dopt%3DAbstract Authors: Zhou B, Yu CX, Chen DZ, Hu XS Dose calculation is a key component in radiation treatment planning systems. Its performance and accuracy are crucial to the quality of treatment plans as emerging advanced radiation therapy technologies are exerting ever tighter constraints on dose calculation. A common practice is to choose either a deterministic method such as the convolution/superposition (CS) method for speed or a Monte Carlo (MC) method for accuracy. The goal of this work is to boost the performance of a hybrid Monte Carlo convolution/superposition (MCCS) method by devising a graphics processing unit (GPU) implementation so as to make the method practical for day-to-day usage. PMID: 21158271 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275734 Mon, 01 Nov 2010 00:00:00 +0100 4275734 http://www.medworm.com/index.php?rid=4275733&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158272%26dopt%3DAbstract Authors: Bliznakova K, Suryanarayanan S, Karellas A, Pallikarakis N This work presents an improved algorithm for the generation of 3D breast software phantoms and its evaluation for mammography. PMID: 21158272 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275733 Mon, 01 Nov 2010 00:00:00 +0100 4275733 http://www.medworm.com/index.php?rid=4275732&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158273%26dopt%3DAbstract Authors: Timberg P, Båth M, Andersson I, Mattsson S, Tingberg A, Ruschin M The purpose of this work was to evaluate the visibility of simulated lesions in 2D digita mammography (DM) and breast tomosynthesis (BT) images of patients. PMID: 21158273 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275732 Mon, 01 Nov 2010 00:00:00 +0100 4275732 http://www.medworm.com/index.php?rid=4275731&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158274%26dopt%3DAbstract Authors: Ma Y, Chang D, Keall P, Xie Y, Park JY, Suh TS, Xing L To develop a 4D volumetric modulated arc therapy (VMAT) inverse planning framework. PMID: 21158274 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275731 Mon, 01 Nov 2010 00:00:00 +0100 4275731 http://www.medworm.com/index.php?rid=4275730&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158275%26dopt%3DAbstract This study aims to evaluate the feasibility of the proposed approach. PMID: 21158275 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275730 Mon, 01 Nov 2010 00:00:00 +0100 4275730 http://www.medworm.com/index.php?rid=4275729&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158276%26dopt%3DAbstract Authors: Lee CY, Chou YH, Huang CS, Chang YC, Tiu CM, Chen CM To develop an intensity inhomogeneity algorithm for breast sonograms in order to assist visual identification and automatic delineation of lesion boundaries. PMID: 21158276 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275729 Mon, 01 Nov 2010 00:00:00 +0100 4275729 http://www.medworm.com/index.php?rid=4275728&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158277%26dopt%3DAbstract Authors: Kang J, Choi Y, Hong KJ, Jung JH, Hu W, Huh YS, Lim H, Kim BT A new positron emission tomography (PET) detector signal processing method, the charge signal transmission approach, is proposed for the development of a hybrid PET-magnetic resonance imaging (MRI). A number of experiments were performed to demonstrate that the Geiger-mode avalanche photodiode (GAPD) charge output could be transmitted to a preamplifier using a long cable without degrading the PET signal performance. PMID: 21158277 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275728 Mon, 01 Nov 2010 00:00:00 +0100 4275728 http://www.medworm.com/index.php?rid=4275727&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158278%26dopt%3DAbstract Authors: Yang Y, Rivard MJ Both the AccuBoost D-shaped and round applicators have been dosimetrically characterized and clinically used to treat patients with breast cancer. While the round applicators provide conformal dose coverage, under certain clinical circumstances the breast skin dose may be higher than preferred. The purpose of this study was to modify the round applicators to minimize skin dose while not substantially affecting dose uniformity within the target volume and reducing the treatment time. PMID: 21158278 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275727 Mon, 01 Nov 2010 00:00:00 +0100 4275727 http://www.medworm.com/index.php?rid=4275726&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158279%26dopt%3DAbstract Authors: Furukawa T, Inaniwa T, Sato S, Shirai T, Takei Y, Takeshita E, Mizushima K, Iwata Y, Himukai T, Mori S, Fukuda S, Minohara S, Takada E, Murakami T, Noda K A project to construct a new treatment facility, as an extension of the existing HIMAC facility, has been initiated for the further development of carbon-ion therapy at NIRS. This new treatment facility is equipped with a 3D irradiation system with pencil-beam scanning. The challenge of this project is to realize treatment of a moving target by scanning irradiation. To achieve fast rescanning within an acceptable irradiation time, the authors developed a fast scanning system. PMID: 21158279 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275726 Mon, 01 Nov 2010 00:00:00 +0100 4275726 http://www.medworm.com/index.php?rid=4275725&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158280%26dopt%3DAbstract Authors: Jette D, Yuan J, Chen W The depth dose of a monoenergetic broad parallel proton beam has been modeled in a number of ways, but evidently not yet for oblique incidence. The purpose of this investigation is to find an accurate analytic formula for this case, which can then be used to model the depth dose of a broad beam with an initial Gaussian angular distribution. PMID: 21158280 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275725 Mon, 01 Nov 2010 00:00:00 +0100 4275725 http://www.medworm.com/index.php?rid=4275724&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158281%26dopt%3DAbstract Authors: Aguiar P, Rafecas M, Ortuño JE, Kontaxakis G, Santos A, Pavía J, Ros D In the present work, the authors compare geometrical and Monte Carlo projectors in detail. The geometrical projectors considered were the conventional geometrical Siddon ray-tracer (S-RT) and the orthogonal distance-based ray-tracer (OD-RT), based on computing the orthogonal distance from the center of image voxel to the line-of-response. A comparison of these geometrical projectors was performed using different point spread function (PSF) models. The Monte Carlo-based method under consideration involves an extensive model of the system response matrix based on Monte Carlo simulations and is computed off-line and stored on disk. PMID: 21158281 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275724 Mon, 01 Nov 2010 00:00:00 +0100 4275724 http://www.medworm.com/index.php?rid=4275723&cid=s_35855_75_f&fid=35855&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21158282%26dopt%3DAbstract Authors: Schildkraut JS, Prosser N, Savakis A, Gomez J, Nazareth D, Singh AK, Malhotra HK Pulmonary nodules present unique problems during radiation treatment due to nodule position uncertainty that is caused by respiration. The radiation field has to be enlarged to account for nodule motion during treatment. The purpose of this work is to provide a method of locating a pulmonary nodule in a megavolt portal image that can be used to reduce the internal target volume (ITV) during radiation therapy. A reduction in the ITV would result in a decrease in radiation toxicity to healthy tissue. PMID: 21158282 [PubMed - in process] (Source: Medical Physics) Medical Physics journals http://www.medworm.com/rss/comments.php?id=4275723 Mon, 01 Nov 2010 00:00:00 +0100 4275723