孤立性肺结节影像特征和误诊分析

Analysis of imaging features and misdiagnosis of solitary pulmonary nodules

目的探讨误诊的孤立性肺结节CT的影像特征,与病理结果对照,并分析误诊原因。方法选取CT诊断错误的30例孤立性肺结节病例,回顾性分析病灶的位置,大小,形状,内部密度,强化特点及影像学特征,以此分析其发生误诊的原因。CT误诊为恶性肿瘤为假阳性组,反之为假阴性组。结果1)结节分布:假阳性组病灶位于右肺上叶3例,右肺下叶4例,左肺上叶4例。假阴性组累及右肺上叶6例,右肺中叶1例,右肺下叶4例,左肺上叶4例,左肺下叶4例;2)强化特点:假阳性组表现为轻度强化4例,中度强化1例,重度强化1例。假阴性组表现为轻度强化1例,中度强化2例,重度强化1例;3)影像特征:假阳性组表现为分叶征7例,毛刺征8例,血管征象6例,胸膜牵拉3例,空泡征0例。假阴性组出现分叶征6例,毛刺征9例,血管征象15例,胸膜牵拉5例,空泡征5例。结论假阳性组误诊原因为病灶出现较多恶性征象,可通过对一些恶性征象的良性特征进行分析,假阴性组多因较少表现出明显的恶性征象而误诊,对血管有无侵犯以及空泡征等早期征象可以辅助诊断,但仍需穿刺活检以明确诊断。

Objective To analyze the misdiagnosis reasons of isolated pulmonary nodules based on the comparative analysis of CT and pathological features.Methods The location,size,shape,internal density,enhancement characteristics and imaging features of 30 cases of solitary pulmonary nodule were retrospectively analyzed to investigate the causes of misdiagnosis.Patients misdiagnosed as malignant tumor by CT were classified as a false positive group,otherwise,a false negative group.Results 1)Nodule distribution in false positive group,the nodule distributing in right upper lobe was found in 3 cases,right lower lobe in 4 cases and left upper lobe in 4 cases.While,in the false negative group,there were 6 cases in the upper lobe of the right lung,1 case in the middle lobe of the right lung,4 cases in the lower lobe of the right lung,and 4 cases in the upper lobe of the left lung,4 cases in the lower lobe of the left lung;2)The characteristics of enhancement in the false positive group,4 cases were mild enhancement,1 case was moderate enhancement,and 1 case was severe enhancement.In the false negative group,there were 1 case of mild enhancement,2 cases of moderate enhancement and 1 case of severe enhancement were confirmed;3)Imaging features in false positive group,lobed sign was found in 7 cases,burr sign in 8 cases,vascular sign was found in 6 cases,pleural traction in 3 cases,vacuole sign in 0 case.In false negative group,lobular sign was found in 6 cases,burr sign in 9 cases,vascular sign in 15 cases,pleural stretch in 5 cases,and vacuole sign in 5 cases.Conclusion The reason of misdiagnosis in false positive group is due to some malignant signs,which can be corrected by the analysis of the typical benign signs.The misdiagnoses of false negative group can attribute to less obvious malignant signs in the patients.The early signs,including vascular invasion and vacuole sign,can help for the diagnosis,but puncture biopsy is suggestive to the patients for identifying the diagnosis of pulmonary nodules.