title: Comparison of the gaze stabilization test and the dynamic visual acuity test in unilateral vestibular loss patients and controls.
abstract: OBJECTIVE
  Compare the dynamic visual acuity test (DVAT) and gaze stabilization test (GST) in patients with unilateral vestibular loss (UVL) and healthy control subjects using a novel computerized testing system prototype.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Tertiary academic referral laboratory.
  
  
  METHODS
  Seventeen UVL patients (median age 62 yr) with bithermal caloric asymmetry (≥49%) or ablative surgery and 17 control subjects (median age 57 yr).
  
  
  METHODS
  Diagnostic.
  
  
  METHODS
  Comparison of DVAT and GST results during self-generated sinusoidal head movements using transient unpredictable target presentations less than 95 milliseconds in duration.
  
  
  RESULTS
  UVL patients had significantly higher DVAT scores toward the lesioned side compared with controls (p = 0.001) and the non-lesioned side (p = 0.003), but the non-lesioned side was not significantly different from controls (p = 0.157). When comparing GST scores, UVL patients required a slower head velocity to maintain visual acuity with movement toward the lesioned side compared with controls (p < 0.001) and the non-lesioned side (p = 0.004). In addition, UVL patients had significantly lower scores toward the non-lesioned side (p = 0.002) compared to controls. ROC curve analysis identified optimal thresholds for abnormal test results to discriminate the lesioned side from controls. A DVAT score greater than or equal to 0.3 ΔlogMAR provided 65% sensitivity and 88% specificity while a GST score less than or equal to 95 degrees/s provided 71% sensitivity and 100% specificity. When GST results were normal, adding DVAT increased overall sensitivity to 88% with 88% specificity.
  
  
  CONCLUSIONS
  Both GST and DVAT demonstrated reduced gaze stabilization toward the lesioned side in the patient group compared with normal controls. Performing GST first and utilizing DVAT when GST was normal provides optimal identification of patients with vestibular dysfunction.
authors.affiliation: *Dizziness and Balance Center, Department of Otolaryngology-Head and Neck Surgery, †Washington University School of Medicine, St. Louis, Missouri, U.S.A.
authors.forename: Courtney C J
authors.initials: CC
authors.lastname: Voelker
authors.forename: Amelia
authors.initials: A
authors.lastname: Lucisano
authors.forename: Dorina
authors.initials: D
authors.lastname: Kallogjeri
authors.forename: Belinda C
authors.initials: BC
authors.lastname: Sinks
authors.forename: Joel A
authors.initials: JA
authors.lastname: Goebel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015837:Vestibular Diseases / Q000503:physiopathology*; D014724:Vestibular Function Tests / Q000379:methods*; D014722:Vestibule, Labyrinth / Q000503:physiopathology; D014787:Vision Tests / Q000379:methods*; D014792:Visual Acuity; D055815:Young Adult