支气管源性囊肿常见CT影像征象分析

CT signs of bronchogenic cysts

目的:探讨支气管源性囊肿常见CT影像征象表现。方法:回顾性分析32例经手术病理证实的支气管源性囊肿病例CT影像资料,通过CT横断面、多平面重建(MPR)观察病变形态、大小、密度,增强观察病变的强化情况及毗邻关系。结果:32例支气管源性囊肿病例,均行CT检查及增强扫描,单发病变,异位型2例(颈部),纵隔型28例(10例位于前纵隔,6例位于中纵隔,12例位于后纵隔),肺内型2例。病变呈类圆形或圆形22例,水滴形或D字形9例,不规则形1例,3例后纵隔病例可见胸膜尾征;1例CT值呈负值,可见分层,囊壁弧形钙化;20例CT值为0~30 HU,11例CT值>30 HU;增强扫描,31例未见强化,1例肺内型合并感染,囊壁明显强化。结合MPR显示,前纵隔病变与周围组织分界清楚;中纵隔病变可表现与支气管关系密切;后纵隔部分病变以宽基底与邻近胸椎相贴,形成D字征,邻近骨质无改变或轻度压迫吸收变薄;肺内病变一般合并感染,或与邻近支气管相通。结论:支气管源性囊肿常见CT影像表现上具有一定相对特征性,熟悉其征象有助于此病的准确诊断。

Objective To investigate the common CT imaging features of bronchogenic cysts.Methods A retrospective analysis was carried out on 32 cases with bronchogenic cysts confirmed by surgery and pathology.CT cross-section and multi-plane reconstruction(MPR)were used for observing the morphology,size and density of the lesions,and enhancement scan for analyzing the enhancement and adjacent relationships.Results All cases had single lesion and underwent CT examination and enhancement scan.There were 2 cases of ectopic type(neck),28 of mediastinum type(10 of anterior mediastinum,6 of middle mediastinum,12 of posterior mediastinum),and 2 of intrapulmonary type.The tumors were quasicircular or circular in 22 cases,droplet-or D-shaped in 9 cases,and irregular in 1 case.Pleural indentations were observed in 3 cases of posterior mediastinum.Negative CT value was found only in 1 case in which there was stratified and the capsule wall was arc-shaped with calcifications;CT value was 0-30 HU in 20 cases and>30 HU in 11 cases.Enhancement scan showed no enhancement in 31 cases,except 1 case of intrapulmonary type with complicated infection and obvious enhancement in the capsule wall.The combination with MPR demonstrated that the anterior mediastinum and surrounding tissues had clear boundaries.Mediastinal lesions may be closely associated with bronchi.The lesions in the posterior mediastinum were attached to the adjacent thoracic vertebra with a broad base,forming the D-sign.The adjacent bones were not affected or became thinner due to slight compression and absorption.Intrapulmonary lesions were accompanied by infection or communicated with adjacent bronchi.Conclusion The common CT signs of bronchogenic cyst are characteristic,which contribute to the accurate diagnosis.