Martin N, Sterkers O, Mompoint D, Julien N, Nahum H
Department of Radiology, Hôpital Beaujon, Clichy, France.
Radiology. 1989 Aug;172(2):521-5. doi: 10.1148/radiology.172.2.2748835.
Symptomatic cholesterol granuloma developed in the middle ear cavities in three cases. At computed tomography (CT) after the administration of contrast material, the granulomas appeared as nonspecific, nonenhanced soft-tissue masses with variable bone erosion. These features are indistinguishable from those of other similar clinical entities, especially cholesteatoma, paraganglioma, and endaural brain hernia. At magnetic resonance (MR) imaging, cholesterol granulomas had a more characteristic appearance. In two cases, the granulomas were depicted as areas of high signal intensity with both T1- and T2-weighted sequences. In the third case, an expansile mastoid cholesterol cyst exhibited medium signal intensity on T1-weighted images, with only a small hyperintense area and a hypointense area located in the cystic wall. Correlations between CT, MR, and microscopic findings show that MR imaging is far superior to CT in tumoral characterization, which is crucial for planning surgical approaches. MR imaging has limitations, however, particularly its inability to depict subtle bone abnormalities.
3例患者中耳腔内出现症状性胆固醇肉芽肿。在注射造影剂后的计算机断层扫描（CT）上，肉芽肿表现为非特异性、无强化的软组织肿块，伴有不同程度的骨质侵蚀。这些特征与其他类似临床病变难以区分，尤其是胆脂瘤、副神经节瘤和耳内脑疝。在磁共振（MR）成像中，胆固醇肉芽肿有更具特征性的表现。2例患者中，肉芽肿在T1加权和T2加权序列上均表现为高信号强度区域。第3例患者中，一个膨胀性乳突胆固醇囊肿在T1加权图像上呈中等信号强度，仅在囊壁上有一个小的高信号区和一个低信号区。CT、MR和显微镜检查结果之间的相关性表明，MR成像在肿瘤特征描述方面远优于CT，这对规划手术入路至关重要。然而，MR成像也有局限性，尤其是无法显示细微的骨质异常。
