中耳炎侵犯迷路的影像表现

Imaging Findings of Labyrinth Involved by Otitis Media

目的:探讨中耳炎侵犯迷路的HRCT和MRI表现及其诊断价值与局限。方法:回顾性分析24例(24耳),经临床综合诊断为中耳炎侵犯迷路患者的HRCT和MRI表现。结果:骨迷路破坏8耳,HRCT诊断7耳,表现为骨迷路破坏,中耳内病变与迷路腔相通。迷路腔淋巴液受侵14耳,HRCT显示骨迷路破坏9耳,骨迷路完好5耳。MRI示8耳迷路腔淋巴液于T1WI上信号升高,T2WI信号无变化,其中7耳增强扫描有明显强化,1耳轻度强化;5耳迷路腔淋巴液于T1WI信号升高,T2WI信号减低,其中4耳明显强化,1耳轻度强化;1耳迷路腔淋巴液于T1WI和T2WI信号无变化,增强后明显强化。迷路增生、硬化1耳,HRCT显示耳蜗骨迷路骨质增厚、硬化,迷路腔变窄;MRI上表现为蜗腔变细。骨迷路广泛破坏1耳,位于耳蜗后部骨迷路内,HRCT显示骨迷路内大片软组织密度影,周围骨质破坏,内部可见形态不规则死骨;MRIT1WI和T2WI显示骨迷路内均呈混杂信号,增强后有不均匀强化。结论:HRCT和MRI可显示中耳炎侵犯迷路的程度,能为临床制定治疗方案提供重要信息。

Objective：To study the High resolution CT（HRCT）and MRI findings of labyrinth involved by otitis media diagnosd by comprehensive clinical features.Methods：HRCT and MRI findings in twenty-four cases（twenty-four ears）with labyrinth involved by otitis media were retrospectively analyzed.Results：Of the 8 ears had only bony labyrinth erosion which proved by surgery,HRCT in seven ears showed bony destruction and the mid ear lesion was in close contact to the labyrinth cavity.Of the 14 ears had labyrinth cavity lymph fluid involvement,9 ears showed bony destruction and 5 ears showed intact bony labyrinth by HRCT.On MRI,8 ears had lymph fluid within lacrimal cavity showing increased signal intensity on T1WI and no change of signal intensity on T2WI;7 ears showed marked enhancement after contrast administration and 1 ear showed mild enhancement.5 ears with lymph fluid showed increase signal intensity on T1WI and decreased signal intensity on T2WI;4 ears had significant enhancement and 1 ear had mild enhancement.1 ear with lymph fluid showed no signal intensity change on both T1 and T2WI,yet obvious enhancement after contrast administration.One ear had labyrinth hyperostosis and sclerosis,cochlea hyperostosis,sclerosis and stricture of labyrinth cavity were assessed on HRCT,narrowing of cochlea cavity was assessed on MRI.Extensive destruction of bony labyrinth was showed in 1 ear,the lesion located within the bony labyrinth posterior to the cochlea,extensive soft tissue density was assessed on HRCT,with surrounding bony destruction and intra-lesion irregular seqestrum;mixed intensities both on T1WI and T2WI within the lesion accompanied with uneven enhancement were revealed on MRI.Conclusion：HRCT and MRI can accurately diagnose the extent and location of labyrinth involved by otitis media,which can provide important information in treatment planning.