title: Vibration-induced nystagmus after acute peripheral vestibular loss: comparative study with other vestibule-ocular reflex tests in the yaw plane.
abstract: OBJECTIVE
  To validate the role of vibration-induced nystagmus (VIN) detecting vestibular asymmetry by comparing several vestibulo-ocular reflex (VOR) parameters in the yaw plane.
  
  
  METHODS
  Prospective validation study for diagnostic test.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  Seventy-four patients with unilateral vestibular loss of acute onset without a history of fluctuating vestibular function and 24 healthy volunteers.
  
  
  METHODS
  Spontaneous nystagmus, head-shaking nystagmus (HSN), and VIN using a 100 Hz handheld vibrator were recorded using a videonystagmography system. Canal paresis on the caloric test and the time constant (TC) on the step velocity test were examined as parameters of the laboratory test.
  
  
  METHODS
  Correlation analysis between horizontal VOR parameters was performed. Receiver operating characteristic (ROC) curves of these parameters were plotted, and the area under the ROC curve (AUC) was compared according to the lower limiting value of TC on step velocity test as well as the presence of unilateral vestibular loss.
  
  
  RESULTS
  VIN was observed in 64 (86%) of 74 patients, and it was directed toward the contralesional side in 98%. VIN showed a significant positive correlation with the canal paresis (r=0.416, p<0.001) and a negative correlation with the TC (r=-0.351, p<0.005). ROC curves of several VOR parameters were compared according to the presence of unilateral vestibular loss. The AUC of VIN was 0.882, and the cutoff intensity of VIN was 2.5 degrees per second. The AUCs of the HSN and spontaneous nystagmus were 0.774 and 0.661, respectively.
  
  
  CONCLUSIONS
  The lateralization value of VIN was comparable with caloric test and superior to HSN. VIN is a useful vestibular test detecting vestibular asymmetry in the evaluation of dizziness.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Gyeonggi-do, South Korea.
authors.forename: Ja-Won
authors.initials: JW
authors.lastname: Koo
authors.forename: Ji-Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Sung Kwang
authors.initials: SK
authors.lastname: Hong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004244:Dizziness / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009759:Nystagmus, Pathologic / Q000209:etiology / Q000503:physiopathology*; D011446:Prospective Studies; D012027:Reflex, Vestibulo-Ocular; D015837:Vestibular Diseases / Q000150:complications / Q000503:physiopathology*; D014725:Vestibular Nerve / Q000503:physiopathology*; D014722:Vestibule, Labyrinth / Q000503:physiopathology*; D014732:Vibration / Q000009:adverse effects*