CT机技术参数与CT片质量的相关性分析

Correlative analysis of technical parameters of CT system and the quality of CT film

目的 初步探索CT机技术参数与CT成像照片质量的关系。方法 对 13台CT机分别进行技术参数检测。采集所检测CT机的若干照片 ,依本研究组制定的“CT片质量临床评分标准”对每张照片进行评分 ,对CT机技术参数与照片评分进行多元线性回归分析。结果 CT机的技术参数 :CT剂量指数 (CTDI)、水的CT值、噪声、均匀性、高对比度分辨率、低对比度分辨率、CT值线性与CT成像照片评分存在线性回归关系 ,但其中仅低对比度分辨率对评分的影响有统计学意义 (t =- 2 4 6 0 ,P =0 0 4 9)。结论 对技术参数检测合格的CT机 ,低对比度分辨率对CT成像照片质量有显著影响 ,其他技术参数对照片质量的影响有待于进一步研究。

Objective To primarily explore the relationship between technical parameters of CT scanner and the quality of CT film.Methods Thirteen sets of CT system were tested and seven technical parameters of each CT scanner were collected,then the CT films from the tested CT system were collected and the quality of CT films were quantitatively analyzed according to 'the clinical evaluative standard of CT film' by our study group.The multi-variable linear regression analysis of technical parameters of the CT scanner and the remarks of the quality of CT film was performed.Results There was linear regression relationship between the physical parameters (including CT dose index,mean CT value of water,noise,uniformity,high contrast resolution,low contrast resolution,and the linear CT value) and the score of CT film.However,among them,only low contrast resolution had statistical significant influence on the score of CT films (t= -2.460,P=0.049).Conclusion Low contrast resolution has significant influence on the quality of CT film and further study of the relationship between other physical parameters and the quality of CT film will be needed.