Recovery of Visual Acuity in People With Vestibular Deficits
Condition: Vestibular Neuronitis; Vestibular Neuronitis, Bilateral; Vestibular Schwannoma
MeSH terms: Neurilemmoma; Neuroma, Acoustic; Vestibular Neuronitis; Guillain-Barre Syndrome; Neuritis
Study type: Interventional

Summary: 
      The purpose of this study is to determine whether exercises relieve the symptoms of dizziness
      and imbalance in people with vestibular deficits and improves the ability to see clearly
      during head movements. We hypothesize that the performance of specific adaptation and
      substitution exercises will result in an improvement in visual acuity during head movements
      while those patients performing placebo exercises will show no improvement.
    

Detailed description: 
      Decrements in visual acuity during head movement in patients with vestibular hypofunction are
      potentially serious problems. This deficit could contribute to decreased activity level,
      avoidance of driving with resultant diminished independence and, ultimately, limited social
      interactions and increased isolation. Oscillopsia occurs because of inadequate
      vestibulo-ocular reflex (VOR) gain and suggests that compensation for the vestibular loss has
      not occurred. The purpose of this study was to examine the effect of an exercise intervention
      on visual acuity during head movement in patients with unilateral and bilateral vestibular
      hypofunction. We hypothesized that 1) patients performing vestibular exercises would have
      improved visual acuity during head movement compared to patients performing placebo
      exercises; 2) there would be no correlation between dynamic visual acuity (DVA) and the
      patients' subjective complaints of oscillopsia; and 3) improvement in DVA would be reflected
      by changes in residual vestibular function as indicated by an increase in VOR gain.

      Patients are assigned randomly to either the vestibular exercise or placebo exercise group.
      The randomization schedule is generated using a computer program for 2-sample randomization.
      The sequence was not concealed from the investigator who obtained consent from the subjects
      and supervised the exercises (SJH). The group assignment (vestibular exercise or placebo
      exercise) was concealed from the participants and from the investigator who performed the
      outcome measures.

      The vestibular exercise group practiced exercises that consisted of adaptation exercises and
      eye-head exercises to targets (Table 1), which were designed to improve gaze stability 16.
      They also performed gait and balance exercises. The placebo exercise group performed
      exercises designed to be 'vestibular-neutral'.
    

Intervention name(s): Control exercises; gaze stabilization exercises
Intervention type(s): Other; Other
Intervention description(s): saccadic eye movements against a plain background; no head movements; adaptation and substitutin exercises encorporating retinal lsip and head movements
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: vestibular rehabilitation; vestibular hypofunction