Evaluation of the Vestibulo-Ocular Reflex Using the Video Head Impulse Test in Patients with Unilateral Chronic Otitis Media

Introduction: The aim of the study was to evaluate the vestibulo-ocular reflex (VOR) using the video head impulse test (vHIT) as a vestibular function assessment method in patients with unilateral chronic otitis media (COM). Methods: Twenty-eight patients with unilateral COM scheduled for middle ear surgery, including 12 males and 16 females with a mean age of 54.5 years, successfully underwent preoperative vHIT. vHIT variables, including VOR gain, VOR gain asymmetry, and the incidence of corrective saccades, were compared between the ipsilesional and contralesional ears. Results: Ten (35.7%) patients reported varying degrees of disequilibrium or lightheadedness. The VOR gain in the ipsilesional and contralesional ears was 1.01 +/- 0.10 and 1.04 +/- 0.11, 0.97 +/- 0.12 and 0.94 +/- 0.13, and 0.97 +/- 0.13 and 1.04 +/- 0.15 in the horizontal canal (HC), anterior canal, and posterior canal (PC), respectively. The average VOR gains in the ipsilesional ears were within the predefined range of normal values; however, the gains in HC and PC significantly decreased compared with those in contralesional ears (p = 0.038 in HC and p = 0.015 in PC). The prevalence of corrective saccades, including overt and/or covert saccades, did not differ significantly between the two ears. Conclusion: This study assessed the pathophysiology of the inner ear affected by chronic middle ear infection by quantitatively comparing the VOR using vHIT. It demonstrated that vHIT can be a practical assessment of vestibular function in patients with COM.