Summary: | 碩士 === 中臺科技大學 === 醫學影像暨放射科學系暨研究所 === 101 === The advent of digital radiographic procedures has brought a revolutionary change to the radiographers daily performance. Traditional film-screen system is replaced by the advent of imaging plate (IP). The image quality is gradually decreased by repeatedly using IP or the life of that. However, how often being used or how old for IP could sacrifice image quality is key issue to be answered.
The three IPs are all AGFA ADC Compact Plus CR reader with MD 4.0 (14×17 inch). Three different part of human bones phantoms and a CIRS Model (CIRS 903 radiology QA phantom, USA) were radiographed with new purchased, 15,000 times of radiographies and seven years IPs respectively. Recorded images were respectively analyzed by using objective evaluation (Moran I test) and subjective evaluation (visual grading analysis, VGA) to understand the changes of image quality.
Subjective evaluation shows no significant difference p>0.05 among three IPs at hand phantom p value 0.051, 0.174, 0.090; elbow phantom p value 0.061, 0.083, 0.069; ankle phantom p value 0.527, 0.101, 0.378; abdomen phantom p value 1.000, 1.000, 0.079. Lower image quality were found by means of objective evaluation, it suggests that IP after seven years should be replaced yet regularly test is suggested for IP being radiographed 15,000 times by Moran I test.
Human visual ability is not sensitive to detect minor change of image quality, it should be carefully double checked by both subjective and objective evaluation to ensure image quality by different life of IPs.
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