摘要目的 分析不同厂家CT和不同探测器排数CT的性能差异,为促进CT的合理配置和使用提供依据.方法 根据2014年哨点监测的结果,在北京市16个区的范围内,共有148家医疗机构配置有CT,采用分层抽样的方法,按照综合医院(共53家)、肿瘤医院(共5家)、中医医院(共25家)、儿童医院(共2家)、社区医院(共30家)和其他专科医疗机构(共33家)进行分层,在各层中按等比分配法,以单纯随机抽样的原则共抽取40家医疗机构,其中综合医院14家,肿瘤医院1家,中医医院7家,儿童医院1家,社区医院8家,其他专科医疗机构9家;将所选医疗机构2012—2014年所检测的所有CT设备作为研究对象,共141台CT设备.按照GB 17589-2011《X射线计算机断层摄影装置质量保证检测规范》对CT进行状态检测,选取CT值(水)、噪声、高对比分辨力、低对比可探测能力等和影像质量密切相关的指标进行比较.结果 不同厂家CT的CT值(水)、噪声和低对比可探测能力差异无统计学意义(P＞0.05),但是不同厂家CT的高对比分辨力差异有统计学意义(χ2＝34.706,P＜0.05);探测器排数＜64排的CT与探测器排数≥64排的CT相比,CT值(水)差异无统计学意义(P＞0.05),噪声、高对比分辨力、低对比可探测能力差异有统计学意义(χ2＝6.978、10.040、15.973,P＜0.05);＜64排不同厂家的CT,发现CT值(水)、噪声、低对比可探测能力差异无统计学意义(P＞0.05),高对比分辨力差异有统计学意义(χ2＝9.941,P＜0.05);≥64排不同厂家的CT,发现CT值(水)、噪声差异无统计学意义(P＞0.05),高对比分辨力、低对比可探测能力差异有统计学意义(χ2＝31.376、32.967,P＜0.05).结论 不同厂家之间CT的性能差异较小,与≥64排CT相比,＜64排CT在噪声和低对比可探测能力方面更有优势,而前者则在高对比分辨力和扫描时间方面更具优势,使其在特定疾病检查较多的医疗机构具有更广泛的应用前景.

abstractsObjective To analyze the performance differences of CT scanners with different detector rows between different manufacturers,and to provide the basis for the rational allocation and use of these CT scanners.Methods According to the result from the sentinel surveillance in 2014,a total of 148 medical institutions were equipped with CT scanners in 16 districts of Beijing,including general hospital(53),cancer hospital(5),TCM hospitals(25),children′s hospitals(2),community hospitals(30)and other specialized medical institutions(33).According to the principle of simple random sampling,40 medical institutions are selected,including 14 general hospitals,1 cancer hospital,7 Chinese medicine hospitals,1 children′s hospital,8 community hospitals and 9 other specialized medical institutions.A total of 141 CT scanners are selected from all CT sets of the selected medical institutions from 2012 to 2014.According to GB 17589-2011 X-ray computed tomography device quality assurance testing status test,four parameters related closely to image quality were tested,including CT value(water),noise,high contrast resolution,and low contrast detectability.Results No significant differences were found in CT value(water),noise and low contrast detectability among CT scanners produced by different manufacturers(P＞0.05),whereas high contrast resolution was found to have a remarkable difference(χ2＝34.706,P＜0.05).Significant differences were found in noise,high contrast resolution and low resolution detectability between the CT scanners with ＜64 detector rows and ≥64 detector rows(χ2＝6.978,10.040,15.973,P＜0.05).However,there is no difference in CT value(water)(P＞0.05).For less-than-64 detector row CT scanners,no significant difference was found in CT value(water),noise and low contrast detectability among different manufacturers(P＞0.05).only high contrast resolution differed remarkably(χ2＝9.941,P＜0.05).For more-than-or equal-to-64 detector row CT scanners,CT value(water)and noise have no differences among different manufacturers(P ＞0.05),whereas,there were significant difference in high contrast resolution and low contrast detectability(χ2＝31.376,32.967,P＜0.05).Conclusions There were a few differences in the performance testing of CT scanners from different manufacturers,and the less-than-64 detector row CT scanners have advantages in noise and low contrast detectability compared with the more-than-64 detector row CT scanners,whereas the latter have advantages in high contrast resolution and scanning time,allowing its wider application in medical institutions with more special diseases.