圆形肺不张的CT诊断(附4例报告)

目的：回顾性复习圆形肺不张的CT表现，并结合文献探讨CT诊断的可能性。方法：分析4例经皮肺穿刺活检及随访证实的圆形肺不张的CT表现及病理结果。着重观察病变的部位，大小，形态，边缘，密度及周围邻 近肺组织，胸膜改变，以确定具有诊断价值的征象。结果：4例病灶均在胸膜下区，分别位于右下叶（2例），左上叶和右上叶，呈圆形或椭圆形高密度灶，最大径分别为2.2cm-4.5cm，均呈周边密度略高的软组织肿块，邻近肺组织支气管，血管呈弧形向肿块集中（“彗星尾”征），均伴有相邻胸膜明显增厚，1例并有少星胸腔积液，病理组织学检查均显示肺组织火车性改变，其中2例伴纤维结缔组织增生，2例检材中含有纤维增生的胸膜组织。结论：胸膜下肿块并“彗星尾”征是圆形肺不张较特异的CT征象，其形成与圆形肺不张的发生有关。

Rounded atelectasis: Diagnosis by CT (Report of 4 cases)

Objective: To retrospectively review the CT finding of rounded atelectasis and to evaluate the probability of the diagnosis by CT.Methods: CT and pathological finding in 4 cases proved by fine-needle biopsy.In order to find the imaging features of CT value in diagnosis,the position, size, configuration, margin, density of the masses and the change of the pulmonary parenchyma and pleura around the masses were observed.Results:All of the four masses were pleural-based location. There were two masses in the right lower lobe, others located the left upper lobe and the right upper lobe.The masses were rounded or oval with the most transversal diameter being 2.2 cm to 4.5 cm.The periphery of the masses was more opaque than the central portion.The comet tail sign could be found in every cases.The adjacent pleural thickening was presence in three cases.The small pleural effusion could be found in another case.The histological features included inflammation of pulmonary parenchyma with hyperplastic connective tissue and pleura.Conclusion:The characteristic findings of the rounded atelectasis is comet tail sign and pleural-based location.