激光打印机应用质量检测及质量控制的初步探讨

The study of quality examination and quality control in laser imager′s application

目的 探讨建立激光打印机应用质量检测方法及质量控制程序。方法 通过对 8家医院 ,分别由Kodak、Agfa生产的 8台激光打印机的调研 ,监测其背景密度、灰阶响应特性、图形几何结构、小对比度变化、分辨率等指标。根据国际电影与电视工程师协会 (societyofmotionpictureandtelevisionengineers,SMPTE)制定的相关标准 ,探讨临床可操作应用的质量检测方法及其质量控制程序。结果 与激光打印机配套的 8台冲洗机均未建立或未严格实施“自动冲洗机的质量控制程序” ,是调研中CT激光照片影像 3 7 5 %不符合标准要求的最主要原因 ;激光打印图像与主机监视器图像一致性好的占 62 5 % (3 0份 ) ,一致性差的占 3 7 5 % (18份 ) ;8台激光打印机 48份CT颅脑照片窗口技术参数符合标准的占 62 5 % (3 0份 ) (窗宽 :80～ 90HU ,窗位 3 5～ 41HU)。 8台激光打印机按临床扫描部位需要设置“输入对应表”曲线的只有 1台。结论 激光打印机的临床应用必须根据相关的国际标准进行验收检测 ,并推行运行中的质量控制程序 ,保证激光打印照片质量稳定可靠。

Objective To discuss and develop a method of quality examination and quality control in laser imager′s application Methods Eight laser imagers produced by Kodak and Agfa in eight hospitals were analyzed for film background density, gray scale responsibility, graphics construction, little contrast distribution, and spatial resolution according to the corresponding criteria established by society of motion picture and television engineers (SMPTE) The method of quality examination and the program of quality control, which could be applied in clinic, were discussed Results The main cause for 18 (37 5%) hard copies of CT studies, which could not match the standard of images, was that the eight automatic film processors coordinated with the laser imagers had not been established with quality control program, or had not been strictly implemented under it The 30 (62 5%) copies were good with the uniformity of the image produced by laser imager and that on the main monitor, whereas 18 (37 5%) copies had bad uniformity Among the 48 hard copies of CT studies of the brain obtained from the eight laser imagers, 30 (62 5%) copies′ window settings were standard (WW: 80-90 HU,WL: 35-41 HU) There was only one imager that had set a curve of 'corresponding input table' according to the clinic demand for the scanning part Conclusion The application of laser imager in clinical use must be checked and accepted according to the related international criteria, and be supervised under the program of quality control, with which the film provided for clinical application has the high quality and stability