Program Information
Comparison of Penumbra Regions Produced by Gamma Knife Model C and Gamma ART 6000 Using Monte Carlo MCNP6 Simulation
N Banaee1*, S Asgari2 , H Nedaie3 , (1) Department of Engineering, Science and Research Branch, Islamic Azad University Tehran, Iran.(2)Department of Medical Radiation, Engineering Faculty, Central Tehran Branch, Islamic Azad University, Tehran, Iran.(3) Odette Cancer Centre, University of Toronto, Toronto, Canada.
Presentations
SU-I-GPD-T-344 (Sunday, July 30, 2017) 3:00 PM - 6:00 PM Room: Exhibit Hall
Purpose: The accuracy of penumbral measurements in radiotherapy is pivotal because dose planning computers require accurate data to adequately modeling the beams, which in turn are used to calculate patient dose distributions. Gamma knife is a non-invasive intracranial technique based on principles of the Leksell stereotactic system for open deep brain surgeries, invented and developed by Professor Lars Leksell. Gamma ART 6000 is the newest version of the American Rotating Gamma System (RGS). Since Gamma ART 6000 is a new system and also Leksell Gamma Knife (LGK) model C is the most widely used system, this study would focus on comparison of penumbra widths produced in LGK model C and Gamma ART 6000 using Monte Carlo MCNP6 code.
Methods: Initially, the structure of both systems including the distribution of ⁶°Co sources, helmet, various collimators and ... were simulated by using Monte Carlo MCNP6 code and after validating the accuracy of simulation with EBT3 radiochromic films, beam profiles of different collimators were plotted and the penumbra width which is defined as the distance between the 20% and 80% isodose lines were calculated.
Results: MCNP6 beam profile calculations showed that the penumbra values of Leksell Gamma knife model C and Gamma ART 6000 for 18, 14, 8 and 4 mm collimators are 9.7, 7.9, 4.3, 2.6 and 8.2, 6.9, 3.6, 2.4, respectively.
Conclusion: The results of this study showed that since Gamma ART 6000 has larger solid angle in comparison with Gamma Knife model C, it produces smaller beam profile penumbras than LGK model C in the direct plane but this difference is not very significant. Therefore, it may be concluded that RGS behaves similarly in terms of dosimetric and mechanical accuracy to the LGK model C.
Contact Email: