Evaluation of transiently evoked otoacoustic emissions and auditory brainstem responses in patients with multiple...

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system. This prospective study was planned to evaluate these changes through brainstem evoked response audiometry (BERA) latency abnormalities and otoacoustic emissions (OAE). This study was performed between September 2009 and May 2010. A total of 160 recordings of BERA and OAE were examined, which were obtained from 80 ears of 40 participants. Twenty of these were MS patients and 20 were healthy volunteers in the control group. Mean ages of the MS group and the control group were 31.3 ± 4.73 and 30.95 ± 4.83 years, respectively. In patients' right ears in the MS group, the wave I, III, and V peak latencies and the I-V interpeak latencies were significantly prolonged compared to those in the control group. In patients' left ears in the MS group, the wave I, III, and V peak latencies and the I-III and I-V interpeak latencies also were significantly prolonged compared to those in the control group. There were no significant differences between the right and left ears for each group regarding wave latencies and intervals. In the MS group, the average of the interaural difference for I-V interpeak latency was significantly prolonged compared to that in the control group. The most reliable diagnostic method in MS is magnetic resonance imaging (MRI). However, sometimes plaques in the central nervous system may not be displayed. The pathologic process may exist and continue before these plaques become detectable on MRI, but electrophysiologic testing such as BERA can demonstrate these changes.