AbstractID: 6672 Title: Dosimetric Performance of Kodak’s EDR2 Film for IMRT QA
The quality assurance process for IMRT treatments includes verification of fluence maps
for each beam and the isodose distribution in at least one plane for the total plan. Film
dosimetry is the most efficient detector for these tests. Until recently, Kodak XV2 film
was the most commonly used film for these tests. Now Kodak has released a new
extended dose range film, EDR2, which has promising features for IMRT QA, most
notably linearity of dose-response up to about 5Gy, and lower energy sensitivity. Testing
was performed to compare the dosimetric performance of XV2 to EDR2 film in the
IMRT QA environment. XV2 and EDR2 were compared for accuracy of central axis
percent depth dose for field sizes from 2x2 cm to 20x20 cm with the film parallel to the
beam. For a series of IMRT plans, individual fluence maps were irradiated and analyzed
with each film and compared to the calculated maps. Also, each film was irradiated by
the total IMRT plan in a coronal plane in a solid water phantom to compare absolute dose
as well as isodoses. The results indicate that EDR2 film is superior to XV2 film in
reproducing percent depth dose data and more nearly matched the calculated isodoses for
the IMRT fluence maps and composite plans without the need for reduction of the total
plan monitor units to avoid film overexposure. EDR2 film is easier to use and more
accurate than XV2 film for IMRT QA testing. Eastman Kodak Company supported this
research.