Preservation of facial nerve function with neurophysiological monitoring during microsurgery of acoustic neuroma

Objective To summarize and analyze the effect of intraoperative neurophysiological monitoring combining with surgical techniques on avoidance of facial nerve injury during microsurgery of acoustic neuroma.Methods 62 patients with acoustic neuroma of medium to large size(diameter≥2.4 cm) received tumor removal via suboccipital retrosigmoidal approach from 2011 to 2012.During operation,the facial nerve was reserved with intraoperative neurophysiological monitoring and the anatomic relationships among the bone,arachnoid,nerve and vascular structure were observed particularly.The patients were followed up for 6 months and the function of the facial nerve was evaluated according to the House-Brackmann system.Results Total tumor resection was achieved in 58 of 62 patients(93.5%) and subtotal in 4(6.5%),no patient died.As for the facial nerve function,recovery of normal function(grade Ⅰ) was achieved in 57 cases(91.9%),grade Ⅱ in 5 cases(8.1%),and none of grade Ⅲ(0.0%).Conclusion Neurophysiological monitoring and microneurosurgical techniques are helpful for total tumor resection and keeping facial nerve anatomic intact in microsurgery of medium to large acoustic neuroma.