计算机辅助检测系统在低剂量肺癌筛查结节检出中的应用价值  

Computer-aided detection of nodule in low-dose CT screening for lung cancer

作　　者：唐威[1] 王建卫[1] 吴宁[1] 黄遥[1] 蔡强[2] 赵世俊[1] 徐晓娟[1] 

机构地区：[1]中国医学科学院北京协和医学院肿瘤医院影像诊断科,100021 [2]山西省人民医院影像中心

出　　处：《中华放射学杂志》2012年第7期619-623,共5页Chinese Journal of Radiology

基　　金：国家“十一五”科技支撑项目（2007BAl05805）;首都医学发展科研基金资助项目（2005.1039）;北京希望马拉松专项基金资助项目（LC2008A14,LC2010838）

摘　　要：目的评价计算机辅助检测系统（CAD）在64层CT低剂量肺癌筛查肺结节检出中的应用价值及其对放射科医师的辅助作用。方法从2007年6月至2008年6月肺癌低剂量筛查数据库共578例中运用纯随机抽样方法抽取100例。低剂量CT扫描参数管电压120kV，管电流30及40mA或管电流调制技术，层厚1．25或1．00mm。由2名胸部影像医师首先阅读胸部CT图像，再应用CAD系统按结节所在位置分为肺外野、肺内野两部分，并将结节检出阈值分别设定为3．0、4．0、5．0mm进行分析。所有结节以2人达成一致作为真结节。分别分析医师双阅片及CAD系统检出结节的能力，并进行McNemar-Bowker检验。结果在100例胸部低剂量CT中，共检出真结节257枚，直径为1．7-18．5mm；分布在双肺外野191枚，双肺内野66枚。CAD系统肺结节检出率为91．1％（234／257），漏诊率为8．9％（23／257），在漏诊的23枚结节中，10枚为实性结节，直径为2．4-6．0mm；13枚为非实性结节，直径为2．1-8．6mm；分布在肺外野17枚，肺内野6枚。放射科医师阅片结节检出率为59．1％（152／257），漏诊率为40．9％（105／257），漏诊结节中94枚为实性结节，10枚为部分实性结节，1枚为非实性结节，结节大小2．4-11．8mm；分布在肺外野69枚，肺内野36枚。结论低剂量螺旋CT肺癌筛查中CAD检出肺结节的能力明显高于医师双阅片，尤其是对肺内野病灶的检出。使用CAD作为辅助诊断时，对非实性结节漏诊率高。Objective To evaluate the performance of computer-aided detection （CAD） system for detection of pulmonary nodules in 64-slice low-dose CT screening and to investigate whether CAD can improve the performance of radiologists in detecting pulmonary nodules. Methods One hundred low-dose screening CT examinations were randomly selected from the database containing 578 consecutive cases between Jun 2007 and Jun 2008. All the examinations were performed on a 64-MSCT scanner with the exposure of 120 kVp, 30 or 40 mA, or automatic exposure control. Before the study started, the screening reports had been made with double reading by two radiologists. All the selected images were analyzed with the lung VCAR software from GE Healthcare with a nodule diameter threshold 3.0 mm. All discrepancies between the screening reports and the CAD results were reviewed and the true non-calcified nodules were determined in consensus by two experienced chest radiologists. Detected nodules were classified by density, size and location. The performance of the double reading and the CAD system were compared and analyzed statistically. McNemar-Bowker test was used for the statistical analysis. Results A total of 257 true non- calcified nodules were determined in all 100 low-dose screening CT examinations. The detection rate of CAD system was 91.1% （234/257） , with the missed rate of 8.9% （23/257）. Twenty three nodules were missedby CAD, in which 10 were solid with the diameter ranged from 2.4 to 6.0 mm, and 13 were nonsolid with the diameter ranged from 2. 1 to 8.6 mm. Of the 23 nodules, 17 were located in the outer zones of lungs and 6 in the inner zones. The double reading showed a detection rate of 59. 1% （152/257）and a missed rate of 40. 9% （ 105/257 ） , which was significantly lower than CAD. The diameter of all the 105 missed nodules by radiologists were ranged from 2.4 to 11.8 mm, in which 94 nodules were solid, 10 were partly solid and 1 was nonsolid, with 69 located in outer zones of lungs and 36 in the inner zones

关 键 词：多发性肺结节 辐射剂量 体层摄影术 X线计算机 

分 类 号：R734.2[医药卫生—肿瘤]