Disorders · Introduction

Bilateral vestibulopathy

When both labyrinths fail, the room stops spinning but the ground stops feeling solid — unsteadiness that worsens in the dark and vision that blurs whenever the head moves. A quiet, disabling disorder, defined by numbers and managed by rehabilitation.

What it is

Trainee

Bilateral vestibulopathy is a chronic syndrome of reduced or absent function in both vestibular labyrinths. The two cardinal symptoms are gait imbalance that worsens in darkness and oscillopsia — visual blurring on head movement from a failed vestibulo-ocular reflex. Because both sides fail together, there is typically little or no spinning vertigo.1

By the numbers

Bilateral vestibulopathy is uncommon but under-recognised, and it carries a real burden — a strong association with falls and a quality-of-life cost comparable to major chronic disease.2 About a quarter of cases remain idiopathic after a full work-up.3

~28/100kestimated adult prevalence (US survey)
~25%remain idiopathic after work-up
<0.6bilateral vHIT VOR gain — a defining threshold
<6°/scaloric sum per ear — a defining threshold

Precipitating events

  • Idiopathic (no cause found)25%
  • Ototoxic (aminoglycoside)18%
  • Genetic / degenerative (incl. CANVAS)16%
  • Bilateral Ménière's12%
  • Autoimmune / infectious12%
  • Neoplastic / surgical / other17%

Illustrative distribution of causes — about a quarter remain idiopathic after a full work-up; ototoxicity is the most important preventable cause.

How this chapter is organised

Key points

  • Chronic, usually symmetric loss of vestibular function on both sides.
  • Cardinal symptoms: imbalance worse in the dark, plus oscillopsia on head movement — with little spinning vertigo.
  • Diagnosis is quantitative (Bárány 2017): symptoms + bilaterally reduced caloric/vHIT/rotational-chair function + no better explanation.
  • Search for a cause — aminoglycoside ototoxicity is the most important preventable one; ~25% stay idiopathic; consider CANVAS.
  • Management is functional — stop the cause, vestibular rehabilitation, avoid suppressants; the vestibular implant is emerging.