Abstract
The vestibular function is in synergism with the oculomotor vergence. Vertigo may be related to vergence disorders and conversely, vestibular pathologies may affect vergence. To consolidate this hypothesis, we conducted a study at the vestibular orthoptic clinic of the Bastogne Hospital. Fourteen patients with vertigo history appearing 2 weeks to 8 years ago, aged 30 to 65 years were studied; at the moment of the eye movement study, no patient had acute attack of vertigo. The origin of vertigo varied (Meniere's disease, organic pathology, sensitivity to visual movement). An assessment with objective measurement of vergence (single-step protocol) was carried out with the REMOBI technology coupled with binocular video-oculography in sitting and standing positions. Four neuro-rehabilitation sessions of vergence eye movements were performed with the double-step in-depth protocol, alternating sitting and standing positions to involve different postural and vestibular functions. An assessment of vergence was done again 1 to 2 months later. The initial assessment revealed problems of magnitude and/or speed or variability of vergence for 11 of the patients relative to controls (published by the group in previous studies). After neuro-rehabilitation, an improvement was observed in eight patients. Patients reported a clear improvement of their self confidence in moving in the space. Posture measures done before rehabilitation comparing eyes fixating or closed or while making near-far vergence eye movements indicated lower medio-lateral acceleration when doing vergence eye movements in patients with vertigo history of functional origin. The results are in favor of the hypothesis of a symbiosis between vergence and vestibular function and the interest of diagnosis and rehabilitation of the vergence disorder in patients with vertigo history in the absence of acute vertigo attack.