Comparison of dose response of radiochromic film measured with He-Ne laser, broadband, and filtered light densitometers.
Dose response curves for GAFChromic MD-55-2 film were measured using three different densitometer systems: a He-Ne laser densitometer, a broadband (white light) densitometer, and a filtered red light densitometer. These were found to differ significantly; the dose needed to achieve a net optical density of 1 (DNOD1) was greater than 100 Gy for the white light densitometer, 56 Gy for the He-Ne densitometer, and only 14.8 Gy for the filtered red light densitometer. This represents approximately a fourfold increase in response for the filtered red light versus the He-Ne laser densitometer, which is a significant improvement. For some patient prescriptions this enables us to achieve an accuracy and precision sufficient to verify daily dose to within 5%.
Reinstein
L E
LE
Department of Radiation Oncology, SUNY at Stony Brook 11794-7028, USA.
Gluckman
G R
GR
D055592:Biophysical Phenomena; D001703:Biophysics; D003720:Densitometry / Q000295:instrumentation* / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D006801:Humans; D007834:Lasers; D008027:Light; D009369:Neoplasms / Q000532:radiotherapy; D011874:Radiometry / Q000295:instrumentation* / Q000706:statistics & numerical data; D011880:Radiotherapy Planning, Computer-Assisted / Q000295:instrumentation / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D013679:Technology, Radiologic / Q000295:instrumentation / Q000706:statistics & numerical data; D014962:X-Ray Film