Study of variation in dose calculation accuracy between kV cone-beam computed tomography and kV fan-Beam computed tomography
Venkatesan Kaliyaperumal, C Jomon Raphael, K Mathew Varghese, Paul Gopu, S Sivakumar, Minu Boban, N Arunai Nambi Raj, K Senthilnathan, P Ramesh BabuJournal of Medical Physics 2017 42(3):171-180
Cone-beam computed tomography (CBCT) images are presently used for geometric verification for daily patient positioning. In this work, we have compared the images of CBCT with the images of conventional fan beam CT (FBCT) in terms of image quality and Hounsfield units (HUs). We also compared the dose calculated using CBCT with that of FBCT. Homogenous RW3 plates and Catphan phantom were scanned by FBCT and CBCT. In RW3 and Catphan ...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Venkatesan Kaliyaperumal C Jomon Raphael K Mathew Varghese Paul Gopu S Sivakumar Minu Boban N Arunai Nambi Raj K Senthilnathan P Ramesh Babu Source Type: research
A feasibility study on the use of tomotherapy megavoltage computed tomography images for palliative patient treatment planning
Yunfei Hu, Mikel Byrne, Ben Archibald-Heeren, Matthew Squires, Amy Teh, Kylie Seiffert, Sonja Cheers, Yang WangJournal of Medical Physics 2017 42(3):163-170
Dedicated rapid access palliative radiation therapy improves patients' access to care, allowing more timely treatment which would positively impact on quality of life. The TomoTherapy (Accuray, Sunnyvale, CA) system provides megavoltage (MV) fan-beam computed tomography (FBCT) as the image guidance technique, and a module called “statRT” that allows the use of these MV FBCT images for direct planning. The possibility of using this ...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Yunfei Hu Mikel Byrne Ben Archibald-Heeren Matthew Squires Amy Teh Kylie Seiffert Sonja Cheers Yang Wang Source Type: research
Performance characteristics of an independent dose verification program for helical tomotherapy
Isaac C. F. Chang, Jeff Chen, Slav YartsevJournal of Medical Physics 2017 42(3):156-162
Helical tomotherapy with its advanced method of intensity-modulated radiation therapy delivery has been used clinically for over 20 years. The standard delivery quality assurance procedure to measure the accuracy of delivered radiation dose from each treatment plan to a phantom is time-consuming. RadCalc®, a radiotherapy dose verification software, has released specifically for beta testing a module for tomotherapy plan dose calculations. RadCalc®'s accuracy for tomotherapy dose calculations was evalu...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Isaac C. F. Chang Jeff Chen Slav Yartsev Source Type: research
Impact of multileaf collimator configuration parameters on the dosimetric accuracy of 6-MV Intensity-Modulated radiation therapy treatment plans
Nick Petersen, David Perrin, Wayne Newhauser, Rui ZhangJournal of Medical Physics 2017 42(3):151-155
The purpose of this study was to evaluate the impact of selected configuration parameters that govern multileaf collimator (MLC) transmission and rounded leaf offset in a commercial treatment planning system (TPS) (Pinnacle3, Philips Medical Systems, Andover, MA, USA) on the accuracy of intensity-modulated radiation therapy (IMRT) dose calculation. The MLC leaf transmission factor was modified based on measurements made with ionization chambers. The table of parameters containing rounded-leaf-end offset values was modified...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Nick Petersen David Perrin Wayne Newhauser Rui Zhang Source Type: research
The impact of the grid size on tomotherapy for prostate cancer
This study used ten treatment plans for prostate cancer. The final dose calculation was performed with “fine” (2.73 mm) and “normal” (5.46 mm) grid sizes. The dose distributions were compared from different points of view: the dose-volume histogram (DVH) parameters for planning target volume (PTV) and organ at risk (OAR), the various indices, and dose differences. The DVH parameters were used Dmax, D2%, D2cc, Dmean, D95%, D98%, and Dmin for PTV and Dmax, D2%, and D2cc for OARs. The various indices used were homogeneity index and...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Motohiro Kawashima Hidemasa Kawamura Masahiro Onishi Yosuke Takakusagi Noriyuki Okonogi Atsushi Okazaki Tetsuo Sekihara Yoshitaka Ando Takashi Nakano Source Type: research
Choice of a suitable dosimeter for photon percentage depth dose measurements in flattening filter-free beams
Silvia Vargas Castrillon, Francisco Cutanda HenríquezJournal of Medical Physics 2017 42(3):140-143
The International Atomic Energy Agency Technical Reports Series-398 code of practice for dosimetry recommends measuring photon percentage depth dose (PDD) curves with parallel-plate chambers. This code of practice was published before flattening filter-free (FFF) beams were widely used in clinical linear accelerators. The choice of detector for PDD measurements needs to be reassessed for FFF beams given the physical differences between FFF beams and flattened ones. The present study compares PDD curves for FFF be...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Silvia Vargas Castrillon Francisco Cutanda Henr & #237;quez Source Type: research
Volumetric-modulated arc therapy lung stereotactic body radiation therapy dosimetric quality assurance: A comparison between radiochromic film and chamber array
Conclusion: Both detectors provide satisfactory results for the QA of plans for VMAT lung SBRT. The film provided greater mean GPR values, afforded greater spatial resolution and was more efficient overall. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Juan Fernando Mata Colodro Alfredo Serna Bern & #225; Vicente Puchades Puchades David Ramos Amores Miguel Alcaraz Ba & #241;os Source Type: research
A phantom study on fetal dose reducing factors in pregnant patients with breast cancer during radiotherapy treatment
Conclusions: Using a lead apron for shielding the abdominal region of a pregnant patient during breast irradiation showed a minor advantage; however, its possible side effects (i.e., increased scattered radiation and skin dose) should also be investigated further to solidify its benefits. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Ak & #305;n Ogretici Ayd & #305;n & #199;ak & #305;r U & #287;ur Akba & #351; Canan K & #246;ksal & #220;mm & #252;han Kalafat Makbule Tamba & #351; Hatice Bilge Source Type: research
Cardiac dose reduction with deep-inspiratory breath hold technique of radiotherapy for left-sided breast cancer
Conclusions: 3DCRTDIBHprovided excellent dosimetric results in patients with left-sided breast cancer without the need for IMRT. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Lalitha Kameshwari Sripathi Parveen Ahlawat David K Simson Chira Ranjan Khadanga Lakshmipathi Kamarsu Shital Kumar Surana Kavi Arasu Harpreet Singh Source Type: research
A hybrid conformal planning technique with solitary dynamic portal for postmastectomy radiotherapy with regional nodes
Conclusion: Hybrid conformal plans with SDP would facilitate improved dose distribution and reduced uncertainty in delivery and promises to be a suitable treatment option for complex postmastectomy CW with regional nodal irradiation. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: K Mohamathu Rafic BS Timothy Peace S Ebenezer Suman Babu I Rabi Raja Singh Source Type: research
Magnitude, impact, and management of respiration-induced target motion in radiotherapy treatment: A comprehensive review
SA Yoganathan, KJ Maria Das, Arpita Agarwal, Shaleen KumarJournal of Medical Physics 2017 42(3):101-115
Tumors in thoracic and upper abdomen regions such as lungs, liver, pancreas, esophagus, and breast move due to respiration. Respiration-induced motion introduces uncertainties in radiotherapy treatments of these sites and is regarded as a significant bottleneck in achieving highly conformal dose distributions. Recent developments in radiation therapy have resulted in (i) motion-encompassing, (ii) respiratory gating, and (iii) tracking methods for adapting the radiation beam aperture to account for the respiration-induce...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: SA Yoganathan KJ Maria Das Arpita Agarwal Shaleen Kumar Source Type: research
Response to the comments on & #8220;The feasibility study of a hybrid coplanar arc technique versus hybrid intensity-modulated radiotherapy in treatment of early-stage left-sided breast cancer with simultaneous-integrated boost. J Med Phys 2017;42:1-8 & #8221;
Yuan-Gui Chen, An-Chuan Li, Wen-Yao Li, Miao-Yun Huang, Xiao-Bo Li, Ming-Qiu Chen, Mutian Zhang, Ben-Hua XuJournal of Medical Physics 2017 42(2):100-100 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - June 16, 2017 Category: Physics Authors: Yuan-Gui Chen An-Chuan Li Wen-Yao Li Miao-Yun Huang Xiao-Bo Li Ming-Qiu Chen Mutian Zhang Ben-Hua Xu Source Type: research
Reference to: Chen YG, Li AC, Li WY, Huang MY, Li XB, Chen MQ, et al. The feasibility study of a hybrid coplanar arc technique versus hybrid intensity-modulated radiotherapy in treatment of early-stage left-sided breast cancer with simultaneous-integrated boost. J Med Phys 2017;42:1-8
Biplab SarkarJournal of Medical Physics 2017 42(2):99-99 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - June 16, 2017 Category: Physics Authors: Biplab Sarkar Source Type: research
Radioactive cobalt-60 teletherapy machine - estimates of personnel dose in mock emergency in patient release during & #8220;source stuck situation & #8221;
Ramamoorthy RavichandranJournal of Medical Physics 2017 42(2):96-98 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - June 16, 2017 Category: Physics Authors: Ramamoorthy Ravichandran Source Type: research
The influence of acquisition mode on the dosimetric performance of an amorphous silicon electronic portal imaging device
Conclusions: For EPID dosimetry application using cine mode, this study recommends the calibration of the EPID images to be undertaken at a large MU. There were no additional corrections that were required when the EPID operated in cine acquisition mode as compared to calibration in integrated mode. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - June 16, 2017 Category: Physics Authors: Omemh Bawazeer Sisira Herath Siva Sarasanandarajah Tomas Kron Pradip Deb Source Type: research
