Alam, Nur Zarifha Zainol
(2015)
Characterization of EBT3 radiochromic film for
precise measurement of output factors in
stereotactic radiosurgery.
Project Report.
Pusat Pengajian Sains Kesihatan, Universiti Sains Malaysia.
(Submitted)
Abstract
Radiochromic film become a demanding tool in a work of
characterizing dosimetric properties in small field stereotactic radiosurgery. The
aim of this project is to perform a comparative study in measuring output factor
using EBT3 radiochromic film and PTW PinPoint Ion Chamber. Output factor measurements using EBT3 films and PTW
PinPoint Ion Chamber were performed using 6MV photon beam from medical
linear accelerator .The measurements was done in solid water phantom and
CNMC Model 74-320 water phantom. Measurements were done at dmax (1.5cm )
depth inside water phantom and 100 cm source surface distance.
Results: Percentage difference of measured output factor with EBT3 Gafchromic film and PTW Ion PinPoint Chamber was approximately 10-11%.
Analysis on dose response for EBT3 and EBT2 gives difference approximately
4% in magnitude. The result obtained for scanning orientation study show
minimal difference in output factors for different side orientation which differs by
less than 2%. Variations for all doses were found to be less than 0.16 (net
difference of optical density) for 4°C and 28°C but 0.026 for 37°C. Net optical
density for the films stored in 37°C recorded huge difference in relative standard
deviation which approximately only 4% compared to 4°C and 28°C which are
34-37% but still represents linear relationship with dose. EBT3 is suitable for measurements of output factor in stereotactic
radiosurgery and can be use on validation of dose when high spatial resolution
is required for clinical practice.
Actions (login required)
 |
View Item |
