耳硬化症的高分辨率CT诊断

The HRCT diagnosis of otosclerosis

目的回顾性分析耳硬化症HRCT表现,并评价HRCT对诊断耳硬化症的诊断价值。方法收集53例经手术确诊的耳硬化症患者CT资料,用MPR技术重建标准横断位、冠状位及镫骨同层显示图像,由三位神经放射学医师对图像进行评价,并分析其影像学表现,计算耳硬化症患者CT检出的敏感性。结果 53例(98耳)患者中,CT确定诊断86耳,病变均表现为点状、条状或小片状低密度灶,其中64耳位于前庭窗前,8耳位于耳蜗周围,7耳位于内听道周围;7耳为多发病变;48耳见镫骨底板增厚。CT可疑诊断7耳患者表现为镫骨底板前部增厚,其中3耳伴有镫骨前脚近底板侧轻度不规则增厚。CT阴性诊断患者5耳,HRCT未见异常改变。本组病例HRCT发现耳硬化症的敏感性为94.9%。结论HRCT可准确显示大部分耳硬化症病灶部位及形态,亚毫米层厚及MPR技术的应用可提高病变的检查率。

Objective To retrospectively analyse the HRCT features of the otosclerosis and to evaluate the sensitivity of HRCT to the diagnosis of otosclerosis. Methods The CT data of 53 patients with otosclerosis were collected. Standard axial, coronal and the image showing all structures of stapes were reformed using MPR technique. The images of 53 patients were evaluated by three neuroradiological doctors. Imaging findings of every patient were analyzed and HRCT detection sensitivity of otosclerosis was evaluated. Results CT confirmed the diagnosis of otosclerosis in 86 ears of 53 patients （98 ears ）. Otosclerosis lesions were shown as lower density lesions, punctate strip or patch. The lesions located anterior of vestibular window in 64 ears, pericochlear in 8 ears and peri internal auditory canal in 7 ears. Multi-lesions were seen in 7 ears. Thickened footplates of stapes were seen in 48 ears. The diagnosis in 7 ears was suspicious on CT images, which only showed thickened anterior part of stapes footpiate in 7 ears and slightly irregular thickened stapes forefoot near bottom side in 3 ears. No abnormal changes were found in 5 ears with otoscelerosis on HRCT images. The HRCT sensitivity in diagnosis of otoscelerosis of this study was 94.9%. Conclusion The features in most patients with otosclerosis can be shown on HRCT images. The images with submillimeter and the application of MPR technology can improve the HRCT sensitivity in diagnosis of otosclerosis.