面神经瘤误诊分析

Misdiagnosis of facial never tumor

目的总结分析面神经瘤误诊的原因,提高对面神经瘤的认识。方法 1993年1月至2006年9月手术治疗的28例面神经瘤患者,11例有误诊的经历。所有患者均行 CT 或 MRI 检查、纯音测听,面神经功能的评估采用 House-Brackman(HB)系统。结果 11例患者被误诊。2例术前被误诊为腮腺肿块,行腮腺浅叶切除术,术中发现肿块来自面神经。4例单侧面神经麻痹长期外院误诊为贝尔面神经麻痹,病史1至8年。由于长期面神经麻痹无好转,行影像学检查发现面神经占位病变。2例复发性面神经麻痹误诊为贝尔面神经麻痹,行影像学检查发现均为面神经膝状神经节占位。1例因左耳渐进性听力下降,体检见外耳道新生物,诊断为外耳道新生物,行活组织检查示神经鞘瘤,进一步影像学检查提示为面神经瘤。1例右耳流脓数年,面神经麻痹1个月。查体示右鼓膜穿孔,CT检查诊断为慢性中耳炎行手术,术中见上鼓室肿块同面神经关系密切,取部分组织送病理,术后病理为面神经鞘瘤。另1例面神经麻痹1年半,CT 检查误诊为先天性胆脂瘤,入院后发现乳突肿块同面神经关系密切,MRI 证实为面神经肿瘤并且侵及腮腺内面神经。11例均经手术和病理证实。结论面神经瘤较罕见,不为大多数临床耳科医生熟悉,在临床中易被漏诊和误诊。临床中,如贝尔面神经麻痹半年内无好转现象或患者表现为反复面神经麻痹,应行影像学检查排除面神经瘤的可能。如患者出现面神经麻痹,CT 示中耳占位并同面神经关系密切时,行 MRI 检查可同中耳胆脂瘤、肉芽、胆固醇肉芽肿等区分。腮腺肿块同面神经总干关系密切者应警惕面神经可能。

Objective To analyze the misdiagnosis of facial nerve tumor and better understand facial nerve tumor. Methods Twenty-eight patients with facial nerve tumor were undergone surgical treatment during January 1993 to September 2006. Eleven patients had been misdiagnosed. All patients were undergone pure tone audiometry ,CT scan or MRI. Facial nerve function was evaluated with House-Brackmann grading system. Results Eleven cases were misdiagnosed. Two cases were misdiagnosed as parotid tumor preoperatively. They were identified as facial never tumor because the masses originated from facial nerve during the surgery and confirmed by pathological examination. Four cases with unilateral facial nerve paralysis lasting from one year to eight years had been misdiagnosed as Bell palsy. Two cases with recurrent facial nerve palsy were misdiagnosed as Bell palsy. Finally MRI and CT demonstrated a mass at the genicular segment of facial nerve. One case with hearing loss and mass in external acoustic meatus was misdiagnoses as external acoustic meatus neoplasm. It was verified as facial schwannomas by biopsy and CT scan. One case with ear discharge,tympanic membrane perforation, soft tissue mass at epitympamum was misdiagnosed as chronic suppurative otitis media, lump was found close to the horizontal segment of facial nerve intraoperatively,and then it was confirmed as facial schwannomas by pathology. One case with soft tissue mass at mastoid and facial paralysis lasting about one and a half years was misdiagnosed as congenital cholesteatoma preoperatively. After admission, MRI study revealed the mass was involved in the facial nerve and parotid gland, and facial nerve tumor was suspected. All the 11 cases were undergone surgery, and the diagnosis was confirmed pathologically. Conclusions Facial nerve tumor was rare and unfamiliar with most of Otologists. The present study showed that the three symptoms or signs should be alert：patient presents with facial paralysis does not partially recovered within six months or patient presents with recurrent facial paralysis, CT scan and MRI should be ordered for these patients to rule out space-occupation along facial nerve. Soft tissue mass associates with the horizontal or vertical segment of facial nerve should be distinguished with Cholesteatoma and ototis media while patient complains of facial paralysis. Parotid neoplasm close to facial nerve should be considered it originates from facial nerve.