Bilateral Vestibular Loss

Abstract

Bilateral vestibular loss is a rare cause of visual disturbance (oscillopsia) and imbalance. When severe, the most common cause is iatrogenic-gentamicin ototoxicity. Bilateral loss is easily diagnosed at the bedside with the dynamic illegible E test. If this test is omitted, it can easily be misdiagnosed as a cerebellar syndrome. Treatment is largely supportive. Care should be taken to avoid medications that suppress vestibular function, and to encourage activity.

Bilateral Vestibular Hypofunction: Challenges in Establishing the Diagnosis in Adults

“…Also, hearing loss or tinnitus does not regularly accompany BVH. While patients with associated episodes of vertigo or hearing loss might seek medical attention early in their clinical course, other patients may have subtle and poorly recognized symptoms, leading to a delay in diagnosis [12,19,38,41,42]. …”

“…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.…”

“…Often, BVH is underdiagnosed in cerebellar disorders, probably partly because cerebellar and vestibular disorders have overlapping signs and symptoms [22,40]. Vestibular disorders may even be improperly diagnosed as a cerebellar syndrome [12]. Therefore, if imbalance is in excess of that expected for the severity of the neurological disorder, one should consider a coexisting BVH [23].…”

“…BVH is characterized by reduced or absent function of both vestibular organs, the vestibular nerves or a combination of both [12], which results in impairment or loss of the major functions of the vestibular organs: gaze stabilization, maintaining balance, postural control and spatial orientation [13]. The best-known symptoms are oscillopsia (blurred vision), chronic disequilibrium, postural instability and impaired spatial orientation [14,15,16].…”

“…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].…”