Vestibulo-cochlear function in inflammatory neuropathies

Abstract

Objective: We aimed to quantify peripheral-vestibular deficits that may contribute to imbalanced stance/gait in patients with inflammatory neuropathies.

Methods: Twenty-one patients (58 ± 15 y [mean age ± 1SD]; chronic-inflammatory-demyelinating-polyneuropathy = 10, Guillain-Barré Syndrome = 5, Anti-MAG peripheral neuropathy = 2, multifocal-motor-neuropathy = 4) were compared with 26 healthy controls. All subjects received video-head-impulse testing (vHIT), caloric irrigation and cervical/ocular vestibular-evoked myogenic-potentials (VEMPs). The Yardley vertigo-symptom-scale (VSS) was used to rate vertigo/dizziness. Postural stability was assessed using the functional gait-assessment (FGA). Pure-tone audiograms (n = 18), otoacoustic emissions (n = 12) and auditory brainstem responses were obtained (n = 12).

Results: Semicircular-canal hypofunction was noted in 9/21 (43%) patients (vHIT = 6; caloric irrigation = 5), whereas otolith function was impaired in 12/21 (57%) (oVEMPs = 8; cVEMPs = 5), resulting in vestibular impairment of at least one sensor in 13/21 (62%). On average, 2.4 ± 1.1 vestibular end organs (each side: anterior/posterior/horizontal canal, utriculus, sacculus; total = 10) were affected. The VSS-scores were higher in patients (16.8 ± 8.6 vs. 9.5 ± 6.2, p = 0.002) but did not correlate with the number of affected organs. Auditory neuropathy was found in 1/12 (8%) patients.

Conclusion: Impairment of one or more vestibular end organs was frequent, but usually mild, possibly contributing to imbalance of stance/gait in inflammatory neuropathies.

Significance: While our data does not support routine vestibular testing in inflammatory neuropathies, this may be considered in selected cases.

Keywords: Chronic inflammatory demyelinating polyneuropathy; Guillain-Barré syndrome; Peripheral neuropathy; Vertigo.