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Analysis the effects of film dosimetry during processing and scanning
HAN Jun, LI Qin, LIANG Zhi-wen, CHEN Mi
Oncology Center, Union Hospital, Huazhong University of Science and Technology;Tongji Medical College, Wuhan 430023, China Corresponding author:LI Qin, Email:lq20092wh@yahoo.com.cn
Abstract Objective To explore the effects of different flushing and scanning processing on optical density (A) responding and set up the clinic quality assurance protocol based on silver halide emulsions radiographic films. Methods Setting different flushing temperature and choosing different batch′s film and developer and fixer or fixer in the same batch with different analyzing dose were performed to analyze the effect on A value;The effect of light uniform, the stabilize work time and the noise of different scanning resolution were discussed. Results The A value at the same dose level would enhance as the temperature increased;the responding curve of dose and A value with different batches of films varied a lot;the responding curve of dose and A value with different batches of films and developer and fixer solution had marked variations;the responding of dose and A with the same batches would show some low. The heterogeneity of the scanner would achieve 0.03;the A value of the same dose would gradually steady while the time of scanning was more than 10 minutes;the affect of noise would increase as the dose and resolution ratio increased. Conclusions The best processing temperature is 29－31℃. Different batches of film couldn′t be confounded. A new calibration must be obtained when the film dosimetry to evaluate dose distribution is used. A 5－10 min warm up for stabilize work and the best setting resolution/depth lever are 72 dpi/16 bit for scanning films are determined.
HAN Jun,LI Qin,LIANG Zhi-wen et al. Analysis the effects of film dosimetry during processing and scanning[J]. Chinese Journal of Radiation Oncology, 2012, 21(3): 285-288.
HAN Jun,LI Qin,LIANG Zhi-wen et al. Analysis the effects of film dosimetry during processing and scanning[J]. Chinese Journal of Radiation Oncology, 2012, 21(3): 285-288.
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2012, Vol. 21 
