基于ASiR-V算法的超低剂量CT应用于肺部非实性结节检出与测量的可行性研究  

A feasibility study of ultra-low-dose CT scan based on adaptive statistical iterative reconstruction-V algorithm in detection and measurement of pulmonary non-solid nodules

作　　者：叶凯 朱巧[1] 李美娇 卢禹流 袁慧书[1] YE Kai;ZHU Qiao;LI Mei-jiao(Department of Radiology,Peking University Third Hospital,Beijing 100191,China)

机构地区：[1]北京大学第三医院放射科,北京100191

出　　处：《放射学实践》2020年第8期967-971,共5页Radiologic Practice

摘　　要：目的:探讨基于ASiR-V算法的超低剂量CT(ULDCT)在肺部非实性结节(NSN)的检出和测量中的临床应用价值。方法:对65例行胸部低剂量CT(LDCT)扫描发现肺部NSN的患者,以选定结节为中心层面、3 cm扫描范围行ULDCT局部扫描。LDCT扫描采用噪声指数14.1的自动kV(120/100 kV)和智能mA模式,ULDCT扫描采用120kV+2.8 mAs的扫描条件,所有数据均采用50%ASiR-V算法及进行重建。分别记录LDCT和ULDCT图像上肺结节的长径,以LDCT检出结果为标准分析ULDCT的检出率,并对影响ULDCT结节检出的因素进行单因素及分组分析。结果:65例患者ULDCT扫描的平均CTDIvol为(0.19±0.00)mGy,较LDCT扫描的(1.77±0.55)mGy减少达89.3%(P<0.001)。LDCT共检出65个NSN,ULDCT对结节的总体检出率为83.1%(54/65),对6 mm以上结节的检出率为96.4%(27/28)。LDCT和ULDCT所测得的结节长径分别为(6.6±2.0)和(6.7±2.1)mm,两者间差异无统计学意义(P>0.05)。单因素方差分析结果表明,平均长径对结节的检出有显著影响(P<0.05),而BMI对结节的检出无显著影响(P>0.05)。结论:在辐射剂量较LDCT降低约90%的条件下,可以尝试将基于ASiR-V算法的ULDCT应用于BMI≤30 kg/m^2患者肺部非实性结节的检出及测量。Objective:To evaluate the clinical value of ultra-low-dose CT(ULDCT)scan based on adaptive statistical iterative reconstruction-V(ASiR-V)algorithm in detection and measurement of pulmonary non-solid nodules(NSN).Methods:Sixty-five patients with pulmonary nodules detected on low-dose chest CT(LDCT)underwent local ULDCT scan in a scan length of 3.0cm with the chosen nodules as the center.Tube voltage and current were set as assist-kV(120/100kV)and smart-mA for LDCT with a noise index(NI)of 14.1HU,and 120kV with 2.8mAs for ULDCT.All CT images were reconstructed using 50%ASiR-V afterwards.The long diameter of pulmonary nodules on LDCT and ULDCT images were measured and recorded respectively.The presence and types of lung nodules found on LDCT was taken as the reference standards,and then the sensitivity of ULDCT was calcula-ted.Univariate and subgroup analysis were used to determine the independent predictors for nodule detection.Results:The mean CTDIvol in ULDCT was(0.19±0.00)mGy,with decreasement of 89.3%compared with(1.77±0.55)mGy of LDCT,and there was statistical difference between the two methods(P<0.001).65 NSNs were showed on LDCT,the general sensitivity of ULDCT for nodule detection was 83.1%(54/65),and 96.4%(27/28)for nodules≥6mm.The mean diameter of NSNs was(6.6±2.0)mm on LDCT and(6.7±2.1)mm on ULDCT with no statistical difference between the two groups(P>0.05).Univariate and subgroup analysis showed that the diameter was the indepen-dent predictor for detection rate(P<0.05),and body mass index(BMI)had no effect on nodule detection(P>0.05).Conclusion:ULDCT can be used in detection and measurement of pulmonary NSN at 10%radiation dose of LDCT for patients with BMI less than 30kg/m^2.

关 键 词：非实性结节 计算机体层成像 辐射剂量 迭代重建 肺癌筛查 

分 类 号：R734.2[医药卫生—肿瘤] R814.42[医药卫生—临床医学]