神经纤维瘤病II型与听觉脑干植入

Neurofibromatosis type 2 and Auditory Brainstem Implantation

目的探讨神经纤维瘤病II型(neurofibromatosis 2,NF-2)(双侧听神经瘤)的临床特征和治疗方法,以及多道听觉脑干植入(auditory brainstem implant,ABI)对双侧听神经瘤切除术后全聋患者听力康复的应用价值。方法回顾性分析了一神经纤维瘤病II型家系3例患者的发病情况和治疗经过。对其中一例患者在经乙状窦后枕下径路切除第二侧听神经瘤时,将12道ABI(MED-EL公司,奥地利)的电极阵置入第四脑室的侧隐窝内,术中行第79、颅神经监测,并结合电刺激脑干诱发电位以校正电极阵位置。术后2月开机并调试。结果文中3例患者早期症状均是以耳部为主,如耳聋、耳鸣、行走不稳感。听觉脑干植入术后开机调试发现电刺激12个电极均能引起听觉反应,无一个引起非听觉反应。结论双侧听神经瘤的临床特点、治疗方法不同于单侧听神经瘤,治疗方案应遵循个体化原则。多导听觉脑干植入能让因双侧听神经瘤导致全聋的患者产生有意义的听觉,术中电极阵准确地植入到脑干耳蜗核是手术成功的关键。对神经纤维瘤病II型患者家庭成员进行筛查有助于该病的早期发现。

Objective Neurofibromatosis 2 （NF - 2） is characterized by bilateral acoustic neuromas, pre - senile lens opacities, dermal, subcutaneous, and plexiform neurofibromas, and brain and spinal cord tumors. Approximately 50% of NF - 2 has a positive family history. Reviewing the history of 3 patients suffering from NF - 2, this paper aims to explore the clinical characteristics, management strategies and surgical approaches for resection of acoustic neuromas. Disscussed is the clinical value of multi- channel auditory brainstem implant （ABI） in auditory rehabilitation of NF - 2 patients with bilateral acoustic neuroma. Methods The clinical data of 3 patients within one family suffering from NF - 2 were retrospectively analyzed. One patient received auditory brainstem implant （ABI） at the same surgery for resection of the second tumor. Presented were the results of preoperative assessment, surgical approach, intra- operative 7th and 9th nerves monitoring, intra- operative electrically evoked auditory brainstem responses （EABR） and post - operative assessment. Results In all 3 patients, otologic symptoms, such as hearing impairment, tinnitus and dizziness, were the most common initial manifestation. The retro - sigmoid approach was used for resection of the tumor while the lateral recess of the fourth ventricle was exposed for placement of the ABI electrode array. For the patient with ABI, initial switch - on was pefformed eight weeks after the surgery under close monitoring. Auditory sensation was through multi - channels stimalation. The additional auditory input obtained could facilitate lip - reading. Conclusion The clinical characteristics and treatment strategies for bilateral acoustic neuromas are different from those of unilateral acoustic neuroma. Individualized management is essential for the success of the treatment. The multi - channel ABI can effectively produce auditory sensation for patient deafened by bilateral acoustic neuromas. The accurate location of the cochlear complex during surgery is the critical factor for success of ABI. Screening of family history for NF - 2 is of help in early identification.