Evaluation of hiigh frequency audiometry and ABR results in patients with unilateral tinnitus

Tinnitus is an auditory hallucination that occurs in the ears or inside the head of a person without acoustic stimuli, affecting 10% of the population. Tinnitus may be closely associated with hearing loss, but some patients do not have clinically detectable hearing loss and the underlying cause is difficult to detect. Our main aim was to determine the pathology by analyzing the ABR waves in patients with unilateral tinnitus by comparing them with the healthy ear, to determine whether the ABR results change with the stimulus repetition rate, and to determine the possibility of hearing loss in the tinnitus ear in Extended High Frequency Audiometry (EHFA). The data of the patients who applied to the otorhinolaryngology outpatient clinic due to unilateral tinnitus were scanned. After scanning the EHFA and ABR data, 48 patients who met the study criteria were identified. As a result of the comparisons, it was found that the latency of the I. wave was significantly prolonged in the ear with tinnitus (p=0.012) and the III. wave and V.wave amplitudes were found to be significantly reduced in the ear with tinnitus (p=0.007). According to the EHFA results, there was no significant difference between ears with and without tinnitus, but the number of ears exceeding the hearing threshold was higher in ears with tinnitus. When the ABR results for Protocol 1 and Protocol 2 were compared according to the stimulus repetition rate, both in the group with and without tinnitus, significant differences were observed in most of the parameters in the two groups, and the sensitivity of the measurements changed with the stimulus repetition rate. It was thought that there might be central and peripheral causes in the ABR wave results. These results made us think that in the etiopathogenesis of tinnitus, primarily distal pathologies of the 8th nerve and the normal hearing thresholds despite this difference in ABR latencies, degenerative changes in the nerve may take time. We suggest that not only peripheral causes are effective in tinnitus pathology, but central pathologies should also be investigated, ABR stimulus repetition rates should be specified in studies, and GYFO should be applied in patients with unilateral tinnitus complaints.