孤立性肺结节的增强CT表现及鉴别诊断

目的探讨良恶性孤立性肺结节（ｓｏｌｉｔａｒｙ ｐｕｌｍｏｎａｒｙ ｎｏｄｕｌｅ，ＳＰＮ）的增强ＣＴ表现及鉴别诊断价值。方法对７５例经手术、病理证实的ＳＰＮ患的ＣＴ图象进行回顾性分析，其中恶性肿瘤５９例，良性肿瘤８例，肉芽肿８例。所用ＣＴ为Ｓｉｅｍｅｎｓ Ｓｏｍａｔｏｍ Ｐｌｕｓ，采用病灶中心层面同床位动态扫描模式，测注射造影剂前后相同层面的ＣＴ值，以３０Ｈｕ作为结节造影后有强化的下限。结果本组中

Solitary pulmonary nodules: CT appearance and differentiation of enhancement with contrast medium

I Purpose To evaluate enhanced appearances and establish differential diagnosis of solitary pulmonary nodules(SPNs) with contrast medium. Methods Seventy- five patiens(53 men, 22 women) with SPN confirmed by surgery and pathology were retrospectively studied. In all cases, dynamic CT scanning had been performed before and after intravenous administration of contrast medium and the density values of lesions were measured in Hounsfield unit. The patterns of enhancement were analyzed in all patients. 30HU was set as the lowest threshold of enhancement. Results there are 66 enchanced nodules and 9 unenchanced in 75 SPNs. According to the enhancement patterns, even enhancement appeared in 38 nodules, uneven enhancement in 21 and edge enhancement in 7. Considering the enhancement degrees, there were 35 mild enhancement nodules, 27 moderate and 4 marked. In view of different biological and pathological characteristics, malignant tumors showed mild or moderate and even or uneven enhancement. Pulmonary adenomas and inflammatory pseudotumors demonstrated moderate and even enhancement. Pulmonary hamartomas and tuberculomas had no enhancement or edge enhancement only. The vascular tumors including artery- vein malformation(AVM)had marked and even enhancement. Conclusion since the different characteristics of location,size, vascularity and cytology of malignant and benign nodules, SPNs show different enhancement patterns and degrees with contrast scanning.