The Strategy For Remaining The Function Of The Facial Never In The Microsurgicaltherapy For Acoustic Neurinoma

Objective:To explore the surgical strategy and techniques of facial nerve preservation in the microsurgical treatment for acoustic neuromas, so that to improve the therapeutic effects of this type of tumors.Methods:A total of 97 patients with unilateral cerebellopontine angle tumor which were eventually dignosticated by pathological tests were collected from the ones hospitalized in the neurosurgy department of the 1st affiliated hospital from January 2006 to January 2011. All of them were treated under microscopical operations either with intraoperative facial nerve monitoring (50 patients) or without intraoperative facial nerve monitoring (47 patients).Six month after the operation,the facial function of the two groups was evaluated respectively ,compared. Therefore, we can analyse factors related to the function residue of the facial nerve after operation by the statistics.Results:In the intraoperative facial nerve monitoring group (M group),.one week after the operation, the rate of normal or near , normal facial nerve function (House- Brackmann grade I ~ II) was 74.00 %(37/50),100.00%(3/3) in the small-size tumor subgroup, 75.00%(15/20)in the moderate-size tumo rgroup and 70.37 %(19/27)in the large-size tumor subgroup;While,in N group,the rate of normal or near normal facial nerve function was57.45 %(27/47), 75.00%(3/4) in the small- size tumor subgroup,63.16%(12/19) in the moderate-size tumor goup and 50.00%(12/24) in the large- size tumor subgroup.Whatever size of the acoustic neuromas,the facial nerve function is better in M group six month after the operation (P <0.05). X2 test was performed to compare the facial function preservations of patients operated with intraoperative facial nerve monitoring with those without it half years after their operations, and P =0.034. Then it was performed again in analysing the the facial function preservations half years after the operations in the large-, medium-and minimal-sized tumor subgroups respectively in the former group to disclose the difference among them, and P =0.026. In the end, the test was used in analysing the same items in the large-, medium-and minimal-sized tumor subgroups respectively in the latter group to find the difference among them, and P =0.021. We can draw a conclusion from the statsitics that the facial function preservation of the former group was always better than the latter regardless of the tumor size, that the preseration was in negative proportion to the tumor size within the same group.Conclusions:Learning the pathological anatomic relationships between the facial nerve and the tumor, skilled microsurgical technique and IFNM are very important for totally tumor resection and facial nerve preservation in the patients with large acoustic neuromas.