外伤后失嗅患者的嗅觉事件相关电位和MRI评估

目的 探讨嗅觉事件相关电位(olfactory event related potentials,OERP)和嗅觉通路MRI对外伤后失嗅的评估价值.方法 回顾性分析24例外伤后失嗅患者的临床资料.所有患者均行详细的病史采集、全面体检、T&T嗅觉检查、鼻内镜检查、OERP测试、颅脑CT和嗅觉通路MRI检查.结果 主观嗅觉测试:双侧完全失嗅20例;单侧完全失嗅,对侧嗅觉减退2例;单侧完全失嗅,对侧嗅觉正常2例.OERP测试:双侧最大嗅刺激均不能引出OERP者20例,单侧最大嗅刺激不能引出OERP者4例;单侧能引出OERP者4例,其中2例能正常引出,另2例OERP幅值下降且潜伏期延长.氨气刺激均能引出鼻内三叉神经化学感受事件相关电位.嗅路MRI检查:嗅球损伤24例次(100%),额叶直回损伤22例次(91.7%),额叶眶回损伤16例次(67%),远端嗅束和颞叶损伤各2例次(8%).结论 OERP能对外伤后嗅觉进行定性和定量的客观整体评估;嗅路MRI能对外伤后失嗅的损伤部位、程度进行客观、精确的评估.两者结合能对嗅觉功能进行全面、客观评价.

Posttraumatic anosmia:olfactory event related potentials and MRI evaluation

OBJECTIVE: Using olfactory event related potentials (OERP) and magnetic resonance to evaluate olfactory function in patients with posttraumatic anosmia. METHODS: Twenty four patients with posttraumatic anosmia were reviewed retrospectively. A thorough medical history, physical examination, nasal endoscopy, T&T olfactory testing, olfactory event-related potentials, brain computed tomography scan and magnetic resonance image of olfactory pathway were performed in all patients. RESULTS: Subjective olfactory testing indicated 20 of 24 patients were birhinal anosmia, 2 with right nostril anosmia and left impairment, 2 with left anosmia and right normal. No OERP were obtained in 24 (20 were birhinal, 4 was monorhinal), except 4 cases with single nostril. Magnetic resonance imaging revealed the injures to the olfactory bulbs (100%), rectus gyrus (91.7%), orbital gyrus (67%), olfactory tracts (8%) and temporal lobes (8%). CONCLUSIONS: OERP can objectively evaluate posttraumatic olfactory function, and magnetic resonance of olfactory pathway can precisely identify the location and extent of injures.