[Analysis of intraoperative EABR characteristics and postoperative efficacy of cochlear implant in patients with tinnitus].

To investigate the characteristics of intraoperative electrically stimulated auditory brainstem responses（EABR） in patients with neural deafness and tinnitus, and to analyze the inhibitory effect of cochlear implantation on tinnitus and its correlation with auditory evoked potential. Twenty-eight adult patients with neuronal deafness accompanied by tinnitus who underwent cochlear implant surgery in the Peking Union Medical College Hospital from 2014 to 2015 were selected, and 10 age-matched patients without tinnitus with the same age were selected as the control group. Preoperative audiology, imaging and tinnitus history of the patients were retrospectively analyzed. During the operation, EABR were used to detect the auditory central functions at all levels, and the electrophysiological characteristics of the two groups were analyzed. The tinnitus handicap inventory（THI） was used to evaluate the severity of tinnitus before and after surgery, and the correlation between EABR results and THI score was analyzed. There were no postoperative complications such as facial paralysis, cerebrospinal fluid leakage, meningitis, etc. , and electroacoustic reactions were observed in all 38 patients. The results of intraoperative EABR showed that there were significant differences in Ⅲ wave amplitude, Ⅴ wave amplitude and Ⅴ wave latency between tinnitus group and control group（<0.05）. The mean C value of （162.78± 24.57）CL and the mean intraoperative EABR threshold of （158.62± 10.31） CL were collected in the two groups 12 months after starting the machine, and there was a significant correlation according to linear correlation analysis（=0.903, <0.01）. The total THI scores of 28 tinnitus patients were 65.00±14.93, 55.00±15.93 and 36.00±21.02 at three time points before, 1 day after and 1 year after cochlear implantation, respectively. The scores of 1 year after cochlear implantation were significantly different by ANOVA（<0.05）, but there was no statistically significant difference 1 day after operation（>0.05）. There was significant correlation between the intraoperative EABR wave Ⅲ amplitude and the linear correlation analysis of THI changes 1 year after operation（=0.873, <0.05）. There is significant difference in intraoperative EABR between patients with neural deafness accompanied with tinnitus and patients without tinnitus. Cochlear electrical stimulation has a good inhibitory effect on tinnitus, and intraoperative EABR can be used as a objective assessment tool for cochlear implant to inhibit tinnitus.