Causative Factors, Epidemiology, and Follow‐up of Bilateral Vestibulopathy

Abstract

Bilateral vestibulopathy (BV) is characterized by impaired or lost function of both peripheral labyrinths or of the eighth nerves. In a review of 255 patients (mean age +/- SD, 62 +/- 16 years) with BV diagnosed in the authors' dizziness unit between 1988 and 2005, 62% of the patients were male. Previous vertigo attacks had occurred in 36%, indicating a sequential manifestation. The definite cause of BV was determined in 24% and the probable cause in 25%. The most common causes were ototoxic aminoglycosides (13%), Ménière's disease (7%), and meningitis (5%). Strikingly, 25% exhibited cerebellar signs. Cerebellar dysfunction was associated with peripheral polyneuropathy in 32% compared with 18% in BV patients without cerebellar signs. In a follow-up study on 82 BV-patients (mean age at the time of diagnosis 56.3 +/- 17.6 years), the frequency and degree of recovery or worsening of vestibular function over time were determined. The patients were reexamined 51 +/- 6 months after the first examination. Electronystagmography with bithermal caloric irrigation was analyzed by measurement of the mean peak slow-phase velocity (SPV) of the induced nystagmus. Statistical analysis of the mean peak SPV revealed a nonsignificant worsening over time (initial mean peak SPV 3.0 +/- 3.5 degrees/s vs. 2.1 +/- 2.8 degrees/s). Only patients with BV due to meningitis exhibited an increasing, but nonsignificant SPV (1.0 +/- 1.4 degrees/s vs. 1.9 +/- 1.6 degrees/s). Forty-three percent of patients subjectively rated the course of their disease as stable, 28% as worsened, and 29% as improved.

Bilateral Vestibular Hypofunction: Challenges in Establishing the Diagnosis in Adults

“…magnetic resonance imaging, computed tomography), lumbar puncture, sensory nerve action potentials, speech assessment, etc. [18,19,20,23,40,89]. However, these tests are mainly used for determination of coexisting problems or the etiology of BVH (table 1), not for an evaluation of vestibular function.…”

“…meningitis, encephalitis, cerebellitis), neoplasms, vascular lesions, and others (table 1). Up to 39% of BVH patients may have a vestibular deficit combined with a neurological disorder [12,20]. In some cases, BVH may precede cerebellar ataxia.…”

“…Nowadays, this symptom complex is known to have many causes, and BVH probably represents a functionally heterogeneous disorder with different combined or isolated deficits of the semicircular canals and/or otolith organs [18]. Most of the etiologies described are presented in table 1[12,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44]. However, its etiology still remains unclear in approximately 50% of all cases [7,19].…”

Instability Due to Drug-Induced Vestibulotoxicity

“…It is well known that ototoxicity is caused by aminoglycoside antibiotics [2,3] . However, ototoxic effects induced by other drugs, such as salicylates, some chemotherapeutic agents, other non-aminoglycoside antibiotics, or sildenafil, have also been reported.…”

Perception of Discomfort Caused by a Unilateral Hearing Loss in People Suffering from a Total Bilateral Vestibular Loss

“…Patients mainly complain of imbalance, blurred vision while walking, and spatial disorientation [2]. So far, no efficient treatment exists for this disorder [3]. However, important steps towards the development of a vestibular implant have recently been made in animals and humans [4,5,6,7,8].…”