CT机的性能检测和临床照片评估

目的：探讨ＣＴ 机的性能检测方法。材料和方法：ＣＴ 设备２０ 台。性能检测参数为层厚、ＣＴ 值线性与对比度标度、均匀性、噪声、空间分辨力、密度分辨力、诊视床定位光精度、诊视床运动精度、剂量指数（ ＣＴＤＩ） 等九项。用Ｃａｔｐｈａｎ体模以及ＲＡＤＣＡＬ 剂量测试设备对ＣＴ 机进行性能参数检测。用近２ 个月多部位照片进行临床照片评估。结果：９ 台ＣＴ 机全部参数合格，其中有３ 台照片质量评估为１ 等，６ 台照片质量评估为２ 等，７ 台ＣＴ 机有１ 项参数不合格，照片质量评估为２ 等，４ 台ＣＴ 机有３ 项以上参数不合格，照片质量评估为２ 等。结论：该检测方法可对ＣＴ 机的各项参数作精确的检测，能够满足ＣＴ 机质量保证性能检测的要求。

Performance Testing and lmage Evaluation for Computed Tomography

Purpose:To develop the methods of performance testing for computed tomography (CT).Materials and methods:20 sets of CT,The measured parformance parameters of CT are slice width,linearity of CT value,uniformity,noise,spatal resolution,low contrast resolution,precision of patient alignment system,scan incrementation and index of CT dose (CTDI).The Catphan phantom and the Radcal dosemeter were used to measure the performance parameters.The patient images which were obtained in recent two months were arbitrarily taken out for evaluation.Results:In 9 sets of CT all the parameters were up to the standards and the quality of images in 3 sets of CT was in first grade ,the quality of image in 6 sets of CT was in second grade:in 7sets of CT only one parameter was not up to the standards and the quality of image in these CT equipments was in second grade;in 4 sets of CT more than 3 performance parameters were not up to the standards and the quality of images in these CT equipments was in second grade.Conclusion:The methods of performance testing for CT work well,and are satisfied for the performance evaluation of CT.