多层螺旋CT及重建技术对气管主支气管肿瘤的诊断

目的 探讨多层螺旋CT(multidetector spiral CT，MSCT)及其多平面容积重建(multiplanar volume refoiraation，MPVR)、容积再现(volume rendering，VR)和仿真支气管镜(virtual bronchoscopy，VB)重建技术对气管、主支气管肿瘤的临床诊断价值。方法 31例可疑气管、主支气管肿瘤病例，进行MSCT薄层扫描，回顾性重建原始扫描数据后形成图像重建数据。在AW工作站，应用MPVR、VR和VB软件对图像重建数据行后处理重建，分别得到MPVR、VR和VB图像。将MSCT原始横轴面图像、MPVR、VR和VB图像显示气管、主支气管肿瘤的结果与手术病理结果进行对照分析。结果 MSCT原始横轴面图像结合MPVR、VR和VB图像，显示的气管、主支气管肿瘤部位(气管19例，右、左主支气管各6例)、形态(窄基底腔内结节型2例、宽基底腔内结节型13例、腔内外肿块型16例)、内部特征(密度均匀、密度低各1例，强化不明显；23例鳞癌、3例腺癌密度较均匀，强化较明显；密度均匀、欠均匀及瘤内点状钙化各1例，强化明显)、管壁外侵犯情况(1例仅突破浆膜层，1例与不张的右肺组织分界不清，14例侵犯范围为4～56mm)、管腔狭窄形态(偏心性1例，不规则26例，环状3例，锥状中断1例)和程度(轻度5例，中度7例，重度19例)，以及测量的沿管壁长轴累及范围(1例为3mm，1例累及整个右主支气管壁和隆突，29例为5～68mm)、主支气管肿瘤与隆突的距离(1例侵犯隆突，1例为16mm，10例大于20mm)等均与手术病理结果相符合。结论 MSCT及其重建技术能够对气管、主支气管肿瘤作出定位、定性和定量诊断，是1种准确的无创性诊断方法，为治疗提供有意义的影像学信息，具有十分重要的临床诊断价值。

Diagnosis of multidetector spiral CT and its reconstruction techniques in trachea and principal bronchus tumors

Objective To investigate the clinical diagnostic value of multidetector spiral CT (MSCT) and its reconstruction techniques including multiplanar volume reformation (MPVR), volume rendering (VR), and virtual bronchoscopy (VB) in the trachea and principal bronchus tumors. Methods Thin slice MSCT scanning was performed in 31 patients with suspected trachea or principal bronchus tumors, and image reconstruction data were formed after retro-reconstructing of initial scanning data. MPVR, VR, and VB images were obtained respectively by postprocessing of image reconstruction data with MPVR, VR, and VB image processing software in AW workstation. The findings of MSCT initial axial images, MPVR, VR, and VB images were compared with surgical and pathological results. Results MSCT initial axial images combined with MPVR, VR, and VB images displayed the locations (tracheae, n=19; right principal bronchi, n=6; left principal bronchi, n=6), morphologies (endoluminal nodular tumors with narrow bases, n=2; endoluminal nodular tumors with wide bases, n=13; intraluminal and extraluminal massive tumors, n=16), internal features (1 had homogeneous density, 1 had low density, they both without obvious enhancement; 23 squamous cell carcinomas and 3 adenocarcinomas had fairly homogeneous density and rather obvious enhancement; 1 had homogeneous density, 1 had inhomogeneous density, 1 had punctate calcification, all with obvious enhancement), extramural invasion situations (broke through only serous membrane, n=1; no clear border with right atelectatic lung tissue, n=1; ranges of extramural invasion 4-56 mm, n= 14), morphologies of luminal stenoses (eccentric, n=1; irregular, n=26; circular, n=3; conical interruption, n=1), extents (mild, n=5; moderate, n=7; severe, n=19); measured longitudinal invasion ranges (only 3 mm, n=1; invaded the whole right principal bronchus wall and carina, n=1; 5-68 mm, n=29), and distances between principal bronchus tumors and carina (invaded carina, n=1; 16 mm, n=1; longer than 20 mm, n=10). The results were all consistent with those of surgery and pathology. Conclusion MSCT and its reconstruction techniques can make diagnosis of location, nature, and quantity of trachea and principal bronchus tumors. As an accurate and noninvasive diagnosis method, they provide significant imaging information for treatment and have very important clinical diagnostic value.