气管旁囊肿的CT表现

CT Findings of Paratracheal Air-containing Cysts

目的 探讨气管旁含气囊肿的CT表现。资料与方法 总结50例胸部常规CT扫描中发现的气管旁含气囊肿,分析其部位、大小、形态、边缘以及临床症状及肺部CT表现。结果 50例气管旁含气囊肿均位于胸腔入口处的气管右侧,其中35例(70％)位于第1～2胸椎水平,47例(94％)位于气管的右后外侧,另有2例在左主支气管旁各还有一含气囊肿。CT均表现为卵圆形或圆形的含气囊肿,囊内有不规则线状、索条状分隔(52％),平均大小为1cm×1cm×2cm,外缘多呈不规则分叶状,壁厚薄不一(84％)。薄层扫描中可见到囊肿和气管间的含气交通细管,三维重建图像可见到软组织密度的交通管道和在气管内壁上的开口。结论 位于胸腔入口处气管右外后侧和气管间有细管状交通的含气囊肿影是本病最可靠的CT征象。它的发生和慢性肺疾患密切相关。

Objective To discuss CT features of paratracheal air-containing cysts. Materials and Methods Fifty cases with paratracheal air cysts found on conventional CT exam were enrolled in this study. The location, size, shape and margin of the lesions, as well as the clinical manifestations were analyzed. Results All the 50 cysts were situated at the thoracic inlet on the right side of the trachea, of which 35 lesions (70% ) were located at T1 ~ T2 level and 47 (94% ) at the right posterolateral side of trachea. Two cases showed an additional air cyst near the left bronchus. On CT scans, all cysts displayed as round or spherical air-containing lesions, with irregular linear septa (52% ) within the cyst and irregular lobulated outline (84%) . The mean size of the lesions was of 1 cm×1 cm×2 cm. On thin-section scans, a fine communicating channel between the cyst and trachea was found in 9 cases. Clinically, 34 patients (68%) showed respiratory symptoms. Conclusion A paratracheal air cyst situated at the thoracic inlet with a fine communicating channel with the trachea is the most reliable CT sign of the disease. Its development is closely related to chronic pulmonary diseases.