成人活动性肺结核的CT表现

CT Findings of Active Pulmonary Tuberculosis in Adults

目的 分析成人活动性肺结核的CT表现 ,明确其CT特征。资料与方法 肺结核组 6 1例 ,肺炎组 4 0例 ,均行常规螺旋CT扫描和HRCT扫描。分析各自的影像学表现 ,并进行统计学分析。结果 肺结核组 :肺实变影6 0例 (98.4 % ) ;合并空洞 2 1例 (34.4 % ) ;小叶中心结节或直径 2～ 4mm分支线样结构 (春芽征 ) 4 2例 (6 8.9% ) ;直径5～ 8mm边缘模糊的结节 5 0例 (82 .0 % ) ;支气管扩张 4 3例 (70 .5 % ) ;不规则线影 4 9例 (80 .3% ) ;疤痕性肺气肿 2 1例 (34.4 % ) ;血管束变形 4 0例 (6 5 .6 % )。肺炎组 :肺实变影 32例 (80 .0 % ) ;合并空洞 5例 (12 .5 % ) ;小叶中心结节或直径 2～ 4mm分支线样结构 (春芽征 ) 16例 (40 .0 % ) ;直径 5～ 8mm边缘模糊的结节 8例 (2 0 .0 % ) ;支气管扩张 2例 (5 .0 % ) ;不规则线影 2 0例 (5 0 .0 % ) ;肺气肿 4例 (10 .0 % ) ;血管束变形 14例 (35 .0 % )。结论 典型的活动性肺结核CT表现有其特点 ,发生在常见或非常见部位的肺实变影 ,伴有局限或广泛的支气管播散灶 ,在HRCT上观察到小叶中心结节或 2～ 4mm分支线样结构 (春芽征 )和 5～ 8mm边缘模糊的结节影 ,均应初诊为活动性肺结核 ;同时出现钙化或纤维化的征象 。

Objective To analyze the CT signs of active pulmonary tuberculosis (TB) in adults, to clarify its CT features.Materials and Methods This study included 61 patients with active TB (TB group) and 40 patients with bacterial pneumonia (pneumonia group). The diagnosis was pathologically proved in all patients. Both conventional helical CT and HRCT scanning were performed in all cases. Imaging findings in each group were observed and statistically analyzed.Results CT findings in TB group included focal pulmonary consolidation (n=60, 98.4%) with cavitation (n=21, 34.4%), 2～4 mm linear branching structure ('tree in bud' sign) or centrilobular nodules (n=42, 68.9%), 5～8 mm sized nodules with poorly defined border (n=50, 82.0%), bronchiectasis (n=43, 70.5%), irregular linear opacity (n=49, 80.3%), cicatricial emphysema (n=21, 34.4%) and bronchovascular distortion (n=40, 65.6%). The above CT signs were also seen in the pneumonia group. The signs included focal pulmonary consolidation (n=32, 80.0%) with cavitation (n=5, 12.5%), 2～4 mm linear branching structure ('tree in bud' sign) or centrilobular nodules (n=16, 40.0%), 5～8 mm nodules with poorly defined border (n=8, 20.0%), bronchiectasis (n=2, 5.0%), irregular linear opacity (n=20, 50.0%), cicatricial emphysema (n=4, 10.0%) and bronchovascular distortion (n=14, 35.0%).Conclusion Classical active pulmonary TB carries certain characteristic CT signs, they are focal pulmonary consolidation shadow, accompanied by localized or diffuse bronchogenic dissemination foci, 'tree in bud' sign on HRCT and poorly defined 5～8 mm sized nodules. Active pulmonary TB should be diagnosed when the above CT signs are observed, and the diagnosis is strongly supported by the presence of calcification and fibrosis.