Bourgouin P M, McLoud T C, Fitzgibbon J F, Mark E J, Shepard J A, Moore E M, Rummeny E, Brady T J
Department of Radiology, Massachusetts General Hospital, Boston 02114.
J Thorac Imaging. 1991 Apr;6(2):22-7. doi: 10.1097/00005382-199104000-00006.
Obstructive pneumonitis frequently occurs distal to hilar bronchogenic carcinomas or in lung adjacent to peripheral tumors. The article evaluates the role of MRI in the differentiation of tumor from pneumonitis. Twelve patients underwent MRI of the thorax before surgery. T1-weighted (SE 310/20) and T2-weighted (SE 2000/60-120) images were obtained through the tumor and presumed areas of pneumonitis. Five histologic types of pneumonitis were identified on pathologic examination of the 12 specimens. Cholesterol pneumonitis, found in 7 patients, was the most common type. Organizing pneumonitis, bronchiectasis with mucus plugs, atelectasis, and abscess were found in 3, 4, 2, and 1 patients, respectively. MRI was able to differentiate tumor from pneumonitis in 5 of 6 patients with a hilar mass and in 5 of 6 patients with a peripheral tumor. This was achieved by a visual difference in signal intensity on heavily T2-weighted (SE 2000/120) images. Cholesterol pneumonitis and bronchiectasis with mucus plugs were always hyperintense relative to tumor, and organizing pneumonitis and atelectasis were isointense and indistinguishable from tumor. MRI can differentiate tumor from pneumonitis provided that pneumonitis is of the cholesterol type or if there are mucus plugs in the collapsed lung.
阻塞性肺炎常发生于肺门支气管源性癌的远侧或周围肿瘤相邻的肺组织。本文评估了MRI在鉴别肿瘤与肺炎中的作用。12例患者在手术前行胸部MRI检查。通过肿瘤及推测的肺炎区域获取T1加权（SE 310/20）和T2加权（SE 2000/60 - 120）图像。对12份标本进行病理检查，确定了5种组织学类型的肺炎。7例患者发现胆固醇性肺炎，为最常见类型。3例、4例、2例和1例患者分别发现机化性肺炎、伴有黏液栓的支气管扩张、肺不张和肺脓肿。MRI能够在6例肺门肿块患者中的5例以及6例周围肿瘤患者中的5例中鉴别肿瘤与肺炎。这是通过在重T2加权（SE 2000/120）图像上信号强度的视觉差异实现的。胆固醇性肺炎和伴有黏液栓的支气管扩张相对于肿瘤总是高信号，而机化性肺炎和肺不张与肿瘤等信号且难以区分。如果肺炎为胆固醇型或塌陷肺内有黏液栓，MRI能够鉴别肿瘤与肺炎。
