title: Gaze stabilization test: a new clinical test of unilateral vestibular dysfunction.
abstract: OBJECTIVE
  Evaluate the sensitivity, specificity, and reliability of the Gaze Stabilization Test (GST) for detection of unilateral vestibular dysfunction.
  
  
  METHODS
  Prospective controlled clinical trial.
  
  
  METHODS
  Tertiary academic referral laboratory.
  
  
  METHODS
  Fourteen patients (mean age, 63.8 yr; range, 43-77 yr) with history of vertigo and greater than 50% bithermal caloric asymmetry; 14 control subjects (mean age, 45.8 yr; range, 23-78 yr).
  
  
  METHODS
  Diagnostic test protocol with computerized system of target presentation and head velocity monitoring.
  
  
  METHODS
  Comparison of peak head velocity with ipsilesional and contralesional head movement-allowing gaze stability by randomly presenting transient (75 ms) targets of three optotypes above static acuity in patients and healthy subjects during self-generated headshake movements.
  
  
  RESULTS
  GST demonstrated 93% specificity, 64% sensitivity, and a reliability index of 0.91 for the detection of unilateral dysfunction with ipsilesional movement. Peak head velocity in healthy subjects averaged 147 degrees per second, whereas ipsilesional velocities dropped significantly to an average of 84 degrees per second. Surprisingly, peak velocities were also significantly reduced to an average of 112 degrees per second with contralesional movements.
  
  
  CONCLUSIONS
  GST is a reliable specific test of gaze stability which has diagnostic and rehabilitative applications in patients with vestibular dysfunction. Reduced contralesional velocities may help explain oscillopsia in patients with unilateral dysfunction.
authors.affiliation: Dizziness and Balance Center, Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA. goebelj@ent.wustl.edu
authors.forename: Joel A
authors.initials: JA
authors.lastname: Goebel
authors.forename: Nilubon
authors.initials: N
authors.lastname: Tungsiripat
authors.forename: Belinda
authors.initials: B
authors.lastname: Sinks
authors.forename: Jaime
authors.initials: J
authors.lastname: Carmody
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006257:Head / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D012720:Severity of Illness Index; D014717:Vertigo / Q000175:diagnosis* / Q000503:physiopathology*; D014724:Vestibular Function Tests; D014722:Vestibule, Labyrinth / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology