Video Head Impulse Test Coherence Predicts Vertigo Recovery in Sudden Sensorineural Hearing Loss With Vertigo

Abstract

Objectives: Labyrinthitis significantly reduces quality of life due to prolonged vestibular symptoms in patients experiencing sudden sensorineural hearing loss with vertigo (SSNHLV). This study employed a novel coherence analysis in the video head impulse test (vHIT) to explore vertigo outcomes in SSNHLV patients.

Methods: A retrospective review was conducted on 48 SSNHLV patients who completed high-dose steroid treatment between December 2016 and April 2023. Additionally, 38 healthy volunteers were prospectively enrolled from November 2022 to April 2023 at our academic tertiary referral center. The magnitude-squared wavelet coherence between eye and head velocities during the vHIT was measured to assess correlations across frequency bands. Recovery from vertigo, determined by a visual analog scale (VAS) score of 0 at both 2 weeks and 2 months, was analyzed using multivariable Cox regression.

Results: The mean VAS for patients with SSNHLV was 5.73±2.45. Higher coherent frequencies in the horizontal semicircular canal (SCC), posterior SCC, and the mean and minimal coherent frequencies of all three SCCs combined were significantly associated with early complete remission of vertigo 2 weeks posttreatment. In the multivariate analysis, the minimal coherent frequency among the three SCCs emerged as an independent factor (hazard ratio, 2.040; 95% CI, 1.776-2.304). Two months posttreatment, in addition to the previously significant parameters, abnormalities in the vestibulo-ocular reflex (VOR) in the posterior SCC, gains in the horizontal and posterior SCCs, total and overt saccades in the horizontal SCC, coherent frequency in the anterior SCC, and mean VOR gain of all three SCCs combined were also statistically significantly related to total relief from vertigo.

Conclusion: The highest minimal coherent frequency among the three SCCs significantly contributed to earlier vertigo relief in patients with SSNHLV. Coherence analysis in vHIT may offer greater sensitivity than time series analysis for predicting the prognosis of vertigo.

Keywords: Sudden Sensorineural Hearing Loss; Vertigo; Video Head Impulse Test; Wavelet Coherence.

Fig. 1.

Video head impulse test results depicting vertigo recovery at the 2 weeks by (A) coherent frequency and (B) vestibulo-ocular reflex (VOR) gain. SCC, semicircular canal.

Fig. 2.

Video head impulse test results depicting vertigo recovery after 2 months by (A) coherent frequency and (B) vestibulo-ocular reflex (VOR) gain. SCC, semicircular canal.

Fig. 3.

(A) Illustration of the magnitude-squared wavelet coherence (MSWC) varying with changes in amplitude and frequency. (B-D) A patient with no recovery of vertigo after 2 weeks of treatment demonstrated normal vestibulo-ocular reflex (VOR) gain (1.13), several compensatory saccades, and an evidently lower coherent frequency (3.36 Hz) in the posterior semicircular canal (SCC). (A) MSWC diminished with inconsistent amplitudes or frequencies in paired signals. (B) Horizontal SCC: VOR gain=1.17 and coherent frequency=6.85 Hz. (C) Anterior SCC: VOR gain=1.47 and coherent frequency=8.38 Hz. (D) Posterior SCC: VOR gain=1.13 and coherent frequency=3.36 Hz.