Evaluation of the Vestibular System by Masseter Vestibular Evoked Myogenic Potentials in Patients With Obstructive Sleep Apnea Syndrome.

Objective: Obstructive Sleep Apnea Syndrome (OSAS) is a common sleep disorder characterized by respiratory arrests and is thought to affect vestibular system functions. In recent years, the Masseter VEMP test has become an alternative method for evaluating vestibular functions. This study aimed to assess the vestibular system through an mVEMP test in OSAS patients and determine the effects of the disease on vestibular functions.

Methods: This prospective study included 36 patients (72 ears) and 36 healthy controls (72 ears) diagnosed with OSAS. All participants underwent the mVEMP test to evaluate the functions of the vestibular system. N1 latency, P1 latency, P1-N1 difference, mean EMG activity, and amplitude values were assessed.

Results: N1 latency was significantly longer in the OSAS group compared with the control group (P=0.013). P1 latency and the P1-N1 difference did not differ significantly between the groups (P=0.273 and 0.098, respectively). The mean EMG activity was significantly lower in the OSAS group compared with the control group (P=0.010). Amplitude was significantly higher in the OSAS group compared with the control group (P=0.024). Significant differences were observed in N1 and EMG values between the groups based on the severity of OSAS.

Conclusion: In this study, significant changes were observed in N1 latency, EMG activity, and amplitude during vestibular evaluation with mVEMP in patients with severe OSAS. It was noted that vestibular responses (N1 and EMG values) were more impacted in the severe OSAS group.