创伤性肺假性囊肿的CT表现及其形成机制的探讨

Posttraumatic pulmonary pseudocyst:CT findings and mechanism of formation

目的总结创伤性肺假性囊肿(PPP)的胸部CT影像特征,探讨其形成机制。方法回顾性分析43例PPP患者,其中男性36例,女性7例;年龄5～70岁,平均年龄30.7岁。行系列胸部CT检查:32例采用Siemens Somatom Sensation 4螺旋CT扫描仪;11例采用Philips Brilliance 64螺旋CT扫描仪。结果 43例患者共发现74个PPP,分布于胸壁下(n=48)、脊柱旁(n=12)、叶间胸膜旁(n=10)、肺韧带旁(n=2)及上纵隔旁(n=2)的肺组织内;大部分PPP呈圆形或类圆形,部分呈不规则形或长椭圆形。比较不同形态的PPP大小与分布显示:圆形或类圆形PPP最大径显著小于另外2组(P<0.05),不规则形多分布于胸壁下而长椭圆形则常见于脊柱旁。结论 PPP形态与分布具有一定的规律,是由不同的损伤机制所造成。多排螺旋CT并多平面重组等后处理技术可更好地观察PPP的形态。

Objective To analyze the CT characteristics of posttraumatic pulmonary pseudocyst（PPP）,and discuss the mechanisms of its formation.Methods A total of 43 PPP patients,included 36 males and 7 females,who were 5-70 years old with a mean age of 30.7.All of them were retrospectively studied serial chest CT films and clinical data.Siemens Somatom Sensation 4 scanner was used for 32 patients and Philips Brilliance 64 scanner was used for 11 cases.Results Seventy-four PPP from 43 patients were found.PPP were located in the subpleural pulmonary parenchyma（n = 48）,thoracic vertebra（n = 12）,intralobar fissure（n = 10）,pulmonary ligament（n = 2） and mediastinum（n = 2）.Most of PPP had round shape and regular margin（n = 44）,part of team had irregular shape（n = 23） or oblong shape（n = 7）.The PPP with round shape were significantly smaller than those with irregular or oblong shape（P〈 0.05）.The irregular shaped PPP was located in subpleural pulmonary parenchyma,whereas the oblong was common in paraspinal region.Conclusion It is demonstrated that the differences of PPP morphology and distribution are related to the injury mechanism,CT scan combined with multi-planar reconstruction could accurately observed the morphological characteristics of PPP.