Function preservation of facial / acoustic nerve during acoustic neuroma microsurgery: report of 40 cases

Objective To investigate the acoustic neuroma microsurgery techniques and facial/acoustic nerve protection without intraoperative electrophysiological monitoring.Methods Retrospective analysis of 40 imaging-proved acoustic neuromas patients underwent suboccipital-retrosigmoid approach for the tumor resection without intraoperative electrophysiological monitoring was performed.Results Total removal of the tumor was achieved in 38 cases(95.0%),with subtotal or partial removal in 2 cases(5.0%).Facial nerve was anatomically reserved in 28 cases(70.0%),with postoperative intact function(House-Brackmann Ⅰ-Ⅱ grade) in 8 cases.There was 30.8%(8/26) of facial nerve function preservation rate in cases with normal preoperative function.Acoustic nerve was anatomically reserved in 18 cases(45.0%),with preserved serviceable hearing in 7 cases.There was 21.9%(7/32) of acoustic nerve function preservation rate in cases with intact preoperative hearing.During follow-up of 27 cases,function reservation of facial nerve and acoustic nerve was observed in 17(63.0%) and 7(25.9%) cases,respectively.Conclusion Familiarity with the anatomy of cerebellopontine region,skillful micro-neurosurgery technique,emphasis of the function protection and postoperative adjuvant therapy are key points of facial / acoustic nerve protection.