计算机X线摄影与传统摄片影像质量对比分析

目的：探讨计算机X线摄影(computed radiography,CR)的影像质量及其主要影响因素。材料和方法：参照卫生部“三甲”医院检查采用的标准,评定甲、乙、丙级和废片。对1000份不同部位CR影像片和1000份与前者部位相同的传统片影像的质量进行评定,分析造成非甲级片的成因,对两组影像质量及影响因素进行统计学分析。结果：CR片的甲片率为53．6％,明显高于传统片42．5％的甲片率,造成CR非甲级片主要成因是体位及铅字号码放置缺陷、摄影体部有异物和摄影前患者准备不佳(98．92％),传统片为76．7％;摄影条件不佳、影像处理技术不良(暗室技术)对CR影像质量影响不大(1．08％),而对传统片影像质量的影响为23．3％。CR片的废片率为0．0％(不包括机器故障造成的废片),低于传统片的2．0％废片率。结论：CR片影像质量明显优于传统片的影像质量,可广泛应用于除动态影像检查外的临床影像学检查。

A Comparative Analysis of Image Quality between CR and Conventional Radiography

Purpose: To investigate the image quality of Computed Radiography (CR) and the main factors affected it. Materials and Methods: Referring to the standard adopted in three "A" hospital evaluation, all those films were classified into 4 levels, i. e. level A B C and D (junk films). The image quality of 1000 copies of CR in different anatomy position was compared with that of conventional films in the same position and same amount, and the related factors, which caused non-level A films were evaluated. Chi square test was used in this study. Results: The rate of level 'A' in CR group (53.6%) is great higher than that in conventional films (42.5%). The main factors caused non-level "A" film including wrong project position, missing of Pb marks, foreign objects and not well-preparation (98.92%), while all the above factors only accounted for 76.7% in conventional films. The effect of selection of inappropriate radiographic parameters and post-processing technique (such as dark-room technique) on CR films is small (1.08%), which is great lower than that on conventional films (23.3%). The rate of level D in CR group is 0.0% (not include those caused by machine problems), which is lower than that in conventional group (2.0%). Conclusion: Image quality of CR films is far better than that of conventional films, thus it can be widely used in clinical radiology.