Tehran University of Medical Sciences

Science Communicator Platform

Stay connected! Follow us on X network (Twitter):
Share this content! On (X network) By
The Effect of Magnetic Field on Linac Based Stereotactic Radiosurgery Dosimetric Parameters Publisher Pubmed



Nedaie HA1, 2 ; Gholami S1, 2 ; Longo F3 ; Banaee N4 ; Hassani M1 ; Sarfehnia A5 ; Pang G5
Authors
Show Affiliations
Authors Affiliations
  1. 1. Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran
  2. 2. Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
  3. 3. Department of Physics, University of Trieste and INFN Trieste, Italy
  4. 4. Department of Medical Radiation, Engineering Faculty, Central Tehran Branch, Islamic Azad University, Tehran, Iran
  5. 5. Odette Cancer Centre, Department of Radiation Oncology, University of Toronto, 2075 Bayview Avenue, Toronto, M4N 3M5, Canada

Source: Biomedical Physics and Engineering Express Published:2020


Abstract

Objective: MR-linac machines are being developed for image-guided radiation therapy but the magnetic field of such machines could affect dose distributions. The purpose of this work was to evaluate the effect of a magnetic field on linac beam dosimetric parameters including penumbra for circular cones used in radiosurgery. Methods: Monte Carlo simulation was conducted for a linac machine with circular cones at 6 MV beam. A homogenous magnetic field of 1.5 T was applied transversely and parallel to the radiation beam. Percentage depth dose (PDD) and beam profiles in a water phantom with and without the magnetic field were calculated. Results: The results have shown that when the magnetic field is applied transversely, the PDDs in the water phantom differ in the buildup region and distant part of PDD curves. The beam profiles at three different depths are all significantly different from those without the magnetic field. The penumbra is greater when a magnetic field has been applied. Conclusion: Linear accelerator-based SRT and SRS use small circular cones. The beam penumbra for these cones can change in the presence of a magnetic field. The perturbation of dose distribution has been also observed in a patient plan due to the presence of a magnetic field. The results of this study show that dose distributions in the presence of a magnetic field must be considered for MR-guided radiotherapy treatments. © 2020 IOP Publishing Ltd.
Related Docs
1. Normal Lung Tissue Complication Probability in Mr-Linac and Conventional Radiotherapy, Reports of Practical Oncology and Radiotherapy (2020)
2. Beam Penumbra Reduction of Gamma Knife Machine Model 4C Using Monte Carlo Simulation, Computer Methods and Programs in Biomedicine (2020)
3. Health Technology Assessment of Image-Guided Radiotherapy (Igrt): A Systematic Review of Current Evidence, Medical Journal of the Islamic Republic of Iran (2016)
4. Application of Geant4 Monte Carlo Simulation in Dose Calculations for Small Radiosurgical Fields, Medical Dosimetry (2018)
5. Beam Quality and the Mystery Behind the Lower Percentage Depth Dose in Grid Radiation Therapy, Scientific Reports (2024)
6. Precise Ebt3 Gafchromic Film Dosimetry for Grid Therapy, Radiation Measurements (2019)
7. Impact of Magnetic Fields on Calculated Aapm Tg-43 Parameters for 192Ir and 60Co Hdr Brachytherapy Sources: A Monte Carlo Study, Applied Radiation and Isotopes (2020)
Experts (# of related papers)
View all Related Experts
Hassan Ali Nedaie (3)
Ghazaleh Geraily (2)