Dosimetry comparition of 6mev electron by gafchromic ebt2 and parallel plan chamber

International Conference on Medical Physics

August 03-05, 2015 Birmingham, UK

Nafise Hasoomi, Mahdi Yazdani and Mansour Naderi

Posters-Accepted Abstracts: J Nucl Med Radiat Ther

Abstract :

Aims: The reference dosimeter for electrons are plan parallel chamber. Film dosimetry has been used extensively as a convenient and rapid means of measuring dose distributions of therapeutic electron beams. Film dosimetry is new way for measurement of isodose, profile and PDD. Quality control of dosimetry parameters in electron is necessary for difference energy of electrons because of unpredictable electron behaviour and scattering. Also Profile is a view that encompasses symmetry and flatness. Methods and Material: One of the newest dosimetry film types that are made by the company ISP is EBT2. These types of films are colourless and sensitive to ionizing radiations and UV radiation beams.This project done based on 2 steps: 1- calibration curve of gafchromic film 2- verification of PDD and profile in gafchromic film and parallel plane chamber. Films were exposed by 6MeV electron, and then films scanned with flat board scanner Microtek 9800XL and them analyased with Image J and Excel software. Results: For all measurements found the maximum uncertainty of 2%.This was calculated through the data of PDD and Profile diagram of 6MeV electron and compare with plan parallel data. Conclusions: film dosimetry is a good way to measure profile and PDD of electron beams, new gafchromic EBT2 films can achieved 2 dimention isodose. in this project results of gafchromic EBT2 and plane parallel in the dosimetry of 6 MeV electron beam in Varian accelerator shows the variation is under 2% in Key-words: film dosimetry ,plan parallel,gafchromic EBT2