الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 141 |  |  |
| | | from | 141 | | |
Abstract
Studying the incidence of normal objective hearing (pure-tone thresholds) among VS patients. Audiological evaluation of this subset of patients along with their management strategy. In addition to investigating the ABR’s diagnostic utility and the effect of tumor size and site on it.
Methods:
This retrospective study was conducted in a Quaternary referral center for managing skull base pathologies. Between 1986 and December 2017, 4,000 patients were diagnosed with VS. Their records were retrospectively reviewed and only patients who complied to the strict criteria of audiological normality were included; detailed as:1) a pure tone audiometric hearing threshold ≤25 dBHL (at the 6-octaves of frequencies from 250 to 8,000 Hz); 2) a WRS >90%; and 3) interaural differences at each frequency ≤10 dB. ABR testing results in addition to radiological imaging data both were assessed.
Results:
The incidence of NH among the 4,000 VS patients was 4.2% in which 162 patients met the strict audiological criteria for NH of this study. The most common symptoms across tumor grades were tinnitus and vertigo; large and giant tumors represented 5.6% of the tumors. The ABR testing yielded a sensitivity of 73.6% using a cutoff point of 0.2 ms for ILDs, yet the false negative rate was 26.3%.
These patients were divided into 2 management groups, W&S (45/162, 25%) and operated patients (123/162, 75%), 6 patients were included in both groups.
The management strategy of this study achieved the goals for treatment of VS. First goal, all tumors were completely removed except for 2 intentional residuals. Second goal, preservation of FN function (House Brackmann I, II and III) was 95.9%. Third goal, possible HP attempts occurred in (50/122) (40.9%) with a HP rate in 44% of the patients. Additionally, there were only 2 cases of postoperative complications with no CSF leakage. The prospect of HP in NH patients did not differ with respect to tumor size.
However, patients with normal preoperative ABR seemed to have better chances of HP and good FN function and vice versa. HP rate was superior for the MCFA as opposed to the RS+RLA. W&S group demonstrated hearing stability in 88.9% of the patients and FN function stability of HB I in 100% of the patients.