【摘要】目的  分析骨内气囊的临床CT表现，提高其认识水平。方法  总结分析8例骨内气囊患者的临床CT资料，男7例，女1例，年龄21-60岁，平均(38.9±6.1)岁。分析病变的部位、大小、形态、密度、边缘、病变所在骨及其周围邻近结构的表现。结果 8例CT表现为单发的气体密度影，其中2例骨内气体密度影周围伴有液体密度影。2例位于股骨头，2例位于邻近肋椎关节的椎体，另4例分别位于紧邻终板的椎体、邻近肩关节的肩胛骨、邻近骶髂关节的髂骨和紧邻肋软骨的肋骨，最大径2-13mm，呈圆形5例，呈椭圆形、分叶状和不规则形各1例。8例边界清楚，1例伴有硬化边，1例骨皮质局部变薄，4例骨皮质中断，2例病变邻近结构同时有积气。结论  骨内气囊常邻近关节和椎间盘，其形成原因与真空现象密切相关。CT表现为边界清楚的骨内含气病变，通过其囊腔内的气体密度可确诊。

Objective To analyze clinical and CT imaging features to improve the recognition level. Methods Clinical and CT data of 8 patients with the intraosseous pneumatocyst were collected, including 7 male and 1 female, aged 21-60 years with mean age of (38.9±6.1) years were analyzed. The location, size, shape, density, margin, the involved bone and the adjacent structures were observed. Results CT showed a solitary gas density within the bone in 8 cases and some liquid density shadow in 2 of 8 cases. 2 cases were located in the femoral head and 2 cases in the vertebral body adjacent to costovertebral joints. Another 4 cases were located in the vertebral body adjacent to endplate, the scapular bone adjacent to the shoulder joint, the ilium adjacent to sacral sacroiliac joint and rib close to the costal cartilage, respectively. The maximum diameter of lesion were 2-13mm. The lesion was round (5 cases), oval (1 case), lobulated (1 case) or irregular (1 case) in shape. The margin of all lesions were clear. Of them, 1 case was accompanied by sclerotic rim, 1 case had cortical bone local thinning, 4 cases had cortical bone interrupt, and 2 cases had a small amount of gas in the adjacent structures at the same time. Conclusions Intraosseous pneumatocyst is generally considered to be secondary to acquired gas-containing bone lesions, usually close to the joint and intervertebral disc. The cause of gas formation is closely related to the vacuum phenomenon. CT can help make a definite diagnosis of the intraosseous pneumatocys using the appearance of the gas density within the bone,