Vestibular alterations assessed using the Video Head Impulse Test (vHIT) in patients with systemic vasculitis at the Luis Guillermo Ibarra National Rehabilitation Institute (Ibarra).

A cross-sectional study.

Abstract

Systemic vasculitis is an inflammatory disease affecting blood vessels of different calibers with multisystem clinical manifestations. Vestibular system involvement and its association with vasculitis have been understudied and underdiagnosed. The main vestibular alterations described are vertigo and vestibulo-ocular reflex (VOR) dysfunction. The latter is detected by the objective Video Head Impulse Test (vHIT), which provides valuable information on the pattern of involvement and its relationship with the type and activity of vasculitis. It also allows for a quantitative evaluation of the vestibulo-ocular reflex, early detection of subclinical vestibular hypofunction, and objective monitoring of vestibular rehabilitation.

Objective: This protocol aims to describe vestibular alterations in the vHIT of patients with systemic vasculitis.

Methods: Study design: Descriptive cross-sectional. Sample: Patients with a confirmed diagnosis of systemic vasculitis treated at the Luis Guillermo Ibarra Ibarra National Rehabilitation Institute in Mexico City. Inclusion criteria: Female and/or male patients aged ≥18 years, diagnosed with vasculitis according to ACR/EULAR criteria, and able to cooperate with vestibular testing. Exclusion criteria: History of head trauma or cervical injuries, previous otologic disease or surgery, use of vestibulotoxic medications, or history of vestibular pathologies.
Evaluation equipment: The Synapsys vHIT Plus model with a remote camera was used.
Application protocol:
Individualized calibration with a visual target at a distance of less than 2.0 m
20 head impulses per plane (horizontal and vertical)
Angular velocity: 150-300°/s (horizontal), 100-200°/s (vertical)
Parameters measured: VOR gain (normal 0.8-1.2), presence of corrective saccades (overt/covert), and interaural asymmetry.

Results: The results of 7 patients with systemic vasculitis were analyzed. The average VOR gain across all channels was described in Table 1. No patients presented corrective saccades, and only two patients with lateral canal asymmetry were reported, with data suggestive of vestibular dysfunction due to an asymmetry of less than 5%.
Conclusions: The above data indicate that VHIT parameters are not altered in patients with vasculitis, except in some cases with interaural asymmetry.
Limitations: An increase in the number of patients is required, and videonystagmography should be supplemented with caloric tests and evoked myogenic potentials to fully assess vestibular function.