肺炎性假瘤的CT影像特点及其鉴别诊断

目的：认识肺炎性假瘤的CT影像表现，分析其与周围型肺癌，结核球的鉴别点。方法：肺炎性假瘤9例，周围型肺癌27例，结核球23例，回顾性分析所有病例的CT平扫及增强扫描表现。结果：肺炎性假瘤圆形2例，类圆形3例，其中边缘有假包膜2例；不规则形2例，分叶状1例，楔形1例。平均直径2．7cm，边缘光滑3例，毛糙或模糊4例，细短毛刺2例；平扫密度均匀3例，中心低密度灶5例，合并空洞2例；多发点状钙化1例。病灶周围有炎性渗出5例。5例增强扫描，均明显强化，均匀强化或不均匀强化，4例增强值在40Hu以上，2例增强值在80～92Hu之间。周围型肺癌主要表现为分叶状外形，细短毛刺，不均匀密度，增强可均匀或不均匀，以不均匀强化居多，增强值22～55Hu。结核球形态规则或不规则，边缘粗大毛刺和实质钙化多见，周围肺内常见卫星病灶，呈包膜状或周围强化，也可不均匀强化或无强化，增强值4～20Hu。结论：肺炎性假瘤CT影像缺乏特征性表现，定性比较困难，周围型肺癌及结核球表现较为特殊，可作为与炎性假瘤鉴别的依据。

CT Imaging Features and Differential Diagnosis of Pulmonary Inflammatory Pseudotumor

Objective:To study the CT manifestations of pulmonary inflammatory pseudotumors and analyze the differential diagnosis among pulmonary inflammatory pseudotumor,peripheral pulmonary carcinoma and tuberculoma.Methods:The CT imaging with horizontal and enhanced scanning were reviewed.Among them,9 cases were pulmonary inflammatory pseudotumor,27 cases were peripheral pulmonary carcinoma,23 cases were tuberculoma.Results:The CT imaging of pulmonary inflammatory pseudotumor were varied.The shape,margin and density were less characteristics.There were 2 cases in round and 3 roundish shape including 2 with pseudocapsule,2 irregular,1 lobulated and 1 wedged one.The average diameter of spot was 2.7 centimeters.The margin was smooth(2 cases),vague(4 cases)and short spiculate (2 cases).The density of the nodules was homogenous (3 cases),low in central part(5 cases).There are 2 cases combined with cavity,1 multi-punctate calcification and 5 inflammatory effusion.All of 5 lesion underwent contrast-enhanced CT were homogeneously or heterogenously enhanced.The value of scanning was over 40 Hu in 4 cases,between 80 and 92 Hu in 2 cases.The spot of peripheral pulmonary carcinoma appeared lobulated shape with short spiculate,heterogenously enhanced scanning from 22 to 55 Hu.There were characteristic satellite-shaped spot with thick spiculate and parenchymatous calcification,less characteristics with enhanced scanning from 4 to 20 Hu in tuberculoma.Conclusions:There are less characteristic manifestation of CT imaging in pulmonary inflammatory pseudotumor.It can provide diagnositic evidence through comparing with the special manifestation of peripberal pulmonary carcinoma and tuberculoma.