Study of a Spherical Phantom for Gamma Knife Dosimetry

Overview

Journal J Appl Clin Med Phys

Specialties Biophysics
General Medicine

Date 2010 Jul 2

PMID 20592697

Citations 2

Authors

Dengsong Zhu

Carlos Austerlitz

Sidi Benhabib

Helvecio Mota

Ron R Allison

Diana Campos

Affiliations

Soon will be listed here.

Abstract

Four 16 cm diameter spherical phantoms were modeled in this study: a homogenous water phantom, and three water phantoms with 1 cm thick shell each made of different materials (PMMA, Plastic WaterTM and polystyrene). The PENELOPE Monte Carlo code was utilized to simulate photon beams from the Leksell Gamma Knife (LGK) unit and to determine absorbed dose to water (Dw) from a single 18 mm beam delivered to each phantom. A score spherical volume of 0.007 cm3 was used to simulate the dimensions of the sensitive volume of the Exradin A-16 ionization chamber, in the center of the phantom. In conclusion, the PMMA shell filled with water required a small correction for the determination of the absorbed dose, while remaining within the statistical uncertainty of the calculations (+/- 0.71). Plastic WaterTM and polystyrene shells can be used without correction. There is a potential advantage to measuring the 4 mm helmet output using these spherical water phantoms.

Citing Articles

Evaluation of Radiation Resistance of Polystyrene Using Molecular Dynamics Simulation.

Yeon Y, Shim H, Park J, Lee N, Park J, Chae M Materials (Basel). 2022; 15(1).

PMID: 35009493 PMC: 8746079. DOI: 10.3390/ma15010346.

FT-IR investigations on effect of high doses of gamma radiation-induced damage to polystyrene and mechanism of formation of radiolysis products.

Vardhan P, Shukla L Radiat Environ Biophys. 2018; 57(3):301-310.

PMID: 29666924 DOI: 10.1007/s00411-018-0740-y.

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