Introducing A Processing Method Of Acoustic Neuroma In The IAC:Scrapping And Hooking Out

Objective: To investigate the pathological anatomy of the IAC in patients suffering from acoustic neuromas.To introduce a method of scrapping and hooking out the tumor in the IAC by Suboccipital retrosigmoid approach(SRA).Methods: 103 cases of acoustic neuromas treated mirosurgically by SRA in our department were analyzed retrospectively.In 67 cases between 2000 and 2007 the posterior wall of the IAC was drilled in order to remove tumors within it.In 36 cases from 2011 to 2014 the tumors in the IAC were scrapped and hooked out. The operation time,the incidence of postoperative cerebrospinal fluid(CSF) leakage, tumors' residual and recurrent rates of the two groups were compared respectively.Results: The operation time of scraping and hooking the IAC's tumor out arranged from 8 to 35 minutes,the average operating time was 17.08 ± 6.40 min.However,tumor removal by drilling the posterior wall of IAC expended 20-78 min, the average time of 42.10 ± 12.40 min.The method of scraping and hooking would result in 1 case(2.8%)of postoperative cerebrospinal fluid leakage,corresponding to the 6 cases(9.0%)in the drilling group.Postoperative imaging data 3 months later demonstrated that residual tumors in the IAC existed in 4 cases(11.1%)of the scrapping group,6 cases(9.0%)in drilling group.Patients with complete tumor resection in IAC had been followed up for 3 years.Respectively,2(7.7%)of 26 cases had tumor recurrence in IAC in scrapping group,and 5(8.9%)of 56 cases in drilling group.Conclusions: Scrapping and hooking the tumors in IAC is a simple and feasible method.It may effectively reduce the incidence of postoperative cerebrospinal fluid leakage.