A New Method for Gain Calculation in Quantified Visuo-vestibular Interaction Test.

Abstract

To develop a new method to quantify visually-enhanced vestibulo-ocular reflex (VVOR) gain, in patients with vestibular function loss, that is mathematically suitable given the nature of the test, and determine the reliability of the method by comparing results with those of the gold standard, the video head impulse test (vHIT). We developed a new method for VVOR gain quantification and conducted a cross-sectional study in patients diagnosed with vestibular function loss and controls, all participants undergoing both a VVOR test and a vHIT. We measured VVOR gain with three different methods: area under the curve (AUC), slope regression, and a Fourier method (VVOR_AUC , VVOR_SP , and VVOR_FR , respectively); and compared these gain values with vHIT gain calculated using the AUC method. Overall, 111 patients were included: 29 healthy subjects and 82 patients with vestibular function loss. Intraclass correlation coefficients (ICC(1,1)) between gain from the gold standard and each of the VVOR gain methods were: 0.68 (CI: 0.61-0.75) for VVOR_AUC , 0.66 (CI: 0.58-0.73) for VVOR_SP and 0.71 (CI: 0.64-0.77) for VVOR_FR . No interference was found between VVOR gain calculation methods and potentially influential variables considered (p ≥ 0.98). The new method for quantifying VVOR gain showed good concordance with the vHIT method. 2: Individual cross-sectional studies with consistently applied reference standard and blinding (Diagnosis) Laryngoscope, 133:3554-3563, 2023.