Evaluation of the peripheral vestibular system due to barotrauma of the inner ear in a hyperbaric environment

Background and Aim: The aim of this study was to investigate conditions that may occur in the peripheral vestibular system due to inner ear barotrauma in independent scuba divers exposed to a hyperbaric environment. Material and Methods: After obtaining ethical approval and informed consent forms, the study was conducted on 45 healthy and voluntary individuals at Trakya University Health Application and Research Center. Otological and audiological examinations were performed on two groups: control group (n=24) and SCUBA group (n=21). Subsequently, cervical vestibular evoked myogenic potentials (cVEMP) assessments were conducted to evaluate peripheral vestibular system functions. The SCUBA group consisted of individuals who had completed a minimum of 75 dives and held a CMAS 2 certification. Otological examinations included otomicroscopic examination, followed by audiological and vestibular assessments. Audiological evaluations included impedance measurements and pure-tone audiometry thresholds (0.25-20 kHz), while vestibular evaluations focused on statistical analysis of P1N1 latency and amplitudes in cVEMP testing. Results: Audiological evaluation revealed statistically significant differences in pure-tone audiometry thresholds at low and high frequencies (p=0.001) in the SCUBA group compared to the control group within the normal hearing range (0-26 dB HL). In our vestibular evaluation, while no statistically significant differences were observed in P1-N1 latencies in cVEMP testing between the SCUBA and control groups (p>0.05), there was a significant increase in amplitudes observed, particularly showing statistical significance (P=0.00038). Conclusion: According to the findings of our study, the increase in P1-N1 amplitudes in cVEMP responses of SCUBA divers exposed to a hyperbaric environment may affect saccular functions due to otolithic structure involvement, and consequently, it may alter pure-tone audiometry thresholds within the normal hearing range due to inner ear barotrauma. KeyWords: Diving, Vestibular Evoked Myogenic Potentials, Barotrauma, Ear Financial Support: This study was supported by Trakya University Scientific Research Projects Unit. Project No: 2023/96