高分辨率CT在慢性化脓性中耳炎手术中的应用

目的：探讨高分辨率计算机断层扫描(HRCT)在显示中耳结构时的优越性及临床价值。方法：分别将51例患者的HRCT图像与术者术中所见进行对比，分析中耳结构(听小骨、面神经管、半规管和天盖等)的特征及存在的解剖变异。结果：锤骨、天盖、砧骨、迷路的HRCT表现与术中所见一致性好，镫骨及面神经管破坏显示差，k(Kappa statistics)值分别为0．840，0．788，0．700，0．560，0．366，0．310。HRCT可发现潜在的手术危险及变异结构，如硬脑膜低位，颈静脉球高位，乙状窦前置，面神经暴露及周围骨质破坏。结论：除面神经管破坏及镫骨结构外，其他中耳重要结构HRCT均能显示清楚，并对制定手术方案，提高手术效果具有重要意义。HRCT应作为中耳乳突手术前常规检查项目。

The role of high-resolution CT in the preoperative assessment of chronic otitis media

Objective:To assess the high-resolution CT scan in depicting the middle ear structures.Method:The surgical findings of 51 ears operated on were retrospectively compared with the CT findings.The followings were analysed: diagnostic features of chronic otitis media(COM) on CT status of the middle ear structures (ossicles, facial nerve canal, semicircular canals and tegmen tympani), and anatomical variations.Result:The radio-surgical agreement was excellent for the malleus (kappa statistics, k= 0.840) and tegmen ( 0.788), good for the incus ( 0.700) and semicircular canals ( 0.56), but poor for the stapes ( 0.366) and facial nerve dehiscence ( 0.310). Potential surgical hazards detected by the scans included: Low lying dura, high jugular bulb,anterior lying sigmoid sinus, facial nerve dehiscence and other situations brought about by the destructive nature of the lesion.Conclusion:There is a good radio-surgical correlation in COM for most middle ear structures except for the integrity of the facial canal and stapes. The scan alerts the surgeon the potential surgical dangers and complications of disease.High-resolution CT scan should be a routine examination prior to middle ear and mastoid surgery.