Evaluation of radiation shielding properties of the polyvinyl alcohol/iron oxide polymer composite
Conclusions: 0.5% of the magnetite gives superior shielding properties compared with other concentrations. It may be due to the presence of 0.3617% of Fe. Elemental weight fraction, atomic number, photon energy, and mass densities are the important parameters to understand the shielding behavior of any material. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: K Srinivasan E James Jabaseelan Samuel Source Type: research
A study to determine whether the volume-weighted computed tomography dose index gives reasonable estimates of organ doses for thai patients undergoing abdomen and pelvis computed tomography examinations
Conclusion: Values of SSDE were similar to the doses calculated for the liver, stomach and kidney, which are covered by the primary beam, confirming that it provides a good estimate of organ-absorbed dose. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Supawitoo Sookpeng Colin J Martin Chitsanupong Butdee Source Type: research
Verification of dosimetric commissioning accuracy of intensity modulated radiation therapy and volumetric modulated arc therapy delivery using task Group-119 guidelines
Conclusion: From the obtained data in this study, we conclude that the commissioning of IMRT and VMAT delivery were found within the limits of TG-119. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Karunakaran Kaviarasu N Arunai Nambi Raj Misba Hamid A Ananda Giri Babu Lingampally Sreenivas Kammari Krishna Murthy Source Type: research
Evaluation and performance of arccheck and film using gamma criteria in pre-treatment quality assurance of stereotactic ablative radiotherapy
Conclusion: The AC results at 3%/3 mm were in good agreement with film dosimetry for most cases. We observed a significant reduction in QA time on using AC for SABR QA. This study showed that AC results are comparable to film dosimetry for all studied sites except for spine IMRT SABR. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Prabhakar Ramachandran Abdulrahman Tajaldeen David Taylor Derrick Wanigaratne Karl Roozen Moshi Geso Source Type: research
Modulation of radiation-induced base excision repair pathway gene expression by melatonin
Conclusion: Our results suggested that MLT in mentioned dose may result in modulation of Ogg1, Apex1, and Xrcc1 gene expression in peripheral blood cells to reduce X-ray irradiation-induced DNA damage. Therefore, administration of MLT may increase the normal tissue tolerance to radiation through enhancing the cell DNA repair capacity. We believed that MLT could play a radiation toxicity reduction role in patients who have undergone radiation treatment as a part of cancer radiotherapy. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Saeed Rezapoor Alireza Shirazi Sakineh Abbasi Javad Tavakkoly Bazzaz Pantea Izadi Hamed Rezaeejam Majid Valizadeh Farid Soleimani-Mohammadi Masoud Najafi Source Type: research
Melatonin ameliorates radiation-induced oxidative stress at targeted and nontargeted lung tissue
Conclusion: Although pretreatment with melatonin did not increase the activity of SOD and GPx in comparison to the radiation groups, this study showed that preadministration of melatonin can ameliorate the oxidative damage induced by ionizing radiation. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Alireza Ghobadi Alireza Shirazi Masoud Najafi Masoud Heidari Kahkesh Saeed Rezapoor Source Type: research
Estimating second malignancy risk in intensity-modulated radiotherapy and volumetric-modulated arc therapy using a mechanistic radiobiological model in radiotherapy for carcinoma of left breast
Conclusions: VMAT plans had a higher risk of developing second malignancy in lung, contralateral breast, heart, and cord compared to IMRT plans. However, the increase in risk was found to be marginal compared to IMRT. Incorporating the age correction factor decreased the risk of contralateral breast SCR. No strong correlation was found between EAR and MU. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Vasanthan Sakthivel Ganesh Kadirampatti Mani Sunil Mani Raghavendiran Boopathy Jothybasu Selvaraj Source Type: research
A unified dose response relationship to predict high dose fractionation response in the lung cancer stereotactic body radiation therapy
Conclusion: The LQ-L(Dt-mt) model is able to fit wide variety of cell survival data over a very wide dose range, and retains the strength of the LQ model in the low-dose range. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Than S Kehwar Kashmiri L Chopra Durg V Rai Source Type: research
Grid block design based on monte carlo simulated dosimetry, the linear quadratic and Hug & #8211;Kellerer radiobiological models
Conclusion: In summary, using MC-based dosimetry, two radiobiological models, and previously published clinical data, we have introduced a method to design a Grid block with optimum therapeutic response. The simulated data were reproduced by experimental data. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Somayeh Gholami Hassan Ali Nedaie Francesco Longo Mohammad Reza Ay Sharifeh A Dini Ali S Meigooni Source Type: research
The impact of dose rate on the accuracy of step-and-shoot intensity-modulated radiation therapy quality assurance using varian 2300CD
Conclusion: IMRT delivery using step-and-shoot technique on Varian 2300CD is impacted by the dose rate and the total amount of segments. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Christopher F Njeh Howard W Salmon Claire Schiller Source Type: research
Assessment of volumetric-modulated arc therapy for constant and variable dose rates
Conclusion: The most significant differences were observed in delivery time and number of MUs. All-in-all, the best CDR for prostate cases was found to be 300 MUs/min and 200 or 300 MUs/min for HN cases. However, VDR plans are still the choice in terms of MU efficiency and plan quality. (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - December 5, 2017 Category: Physics Authors: Mariluz De Ornelas-Couto Ivaylo Mihaylov Nesrin Dogan Source Type: research
News
Pratik KumarJournal of Medical Physics 2017 42(3):196-197 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Pratik Kumar Source Type: research
Handbook of radiobiology
BS RaoJournal of Medical Physics 2017 42(3):194-195 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: BS Rao Source Type: research
Artificial body fluid as tissue substitute for radiotherapy beam analysis: A theoretical evaluation of its electron density information
Ramamoorthy RavichandranJournal of Medical Physics 2017 42(3):191-193 (Source: Journal of Medical Physics)
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: Ramamoorthy Ravichandran Source Type: research
Quality assurance and average glandular dose measurement in mammography units
This study evaluated different operating parameters through mechanical test, accelerating voltage (kVp) accuracy test, machine output measurement, half-value layer measurement, calibration of compression device, image quality assessment, measurement of leakage radiation, radiation survey, and average glandular dose (AGD) measurements using stereotactic needle biopsy phantom. The results show that out of eight mammography units, only a single mammography unit (U-1) passed all QA tests and 2 units passed 7 tests, 2 units passed 6 tests, and 3 units passed 5 tests out of 8 QA tests. In unit 5, the AGD value was 4 and 1.93 mGy...
Source: Journal of Medical Physics - September 13, 2017 Category: Physics Authors: C Senthamil Selvan CS Sureka Source Type: research
