title: The video ocular counter-roll (vOCR): a clinical test to detect loss of otolith-ocular function.
abstract: CONCLUSIONS
  vOCR can detect loss of otolith-ocular function without specifying the side of vestibular loss. Since vOCR is measured with a simple head tilt maneuver, it can be potentially used as a bedside clinical test in combination with video head impulse test.
  
  
  OBJECTIVE
  Video-oculography (VOG) goggles are being integrated into the bedside assessment of patients with vestibular disorders. Lacking, however, is a method to evaluate otolith function. This study validated a VOG test for loss of otolith function.
  
  
  METHODS
  VOG was used to measure ocular counter-roll (vOCR) in 12 healthy controls, 14 patients with unilateral vestibular loss (UVL), and six patients with bilateral vestibular loss (BVL) with a static lateral head tilt of 30°. The results were compared with vestibular evoked myogenic potentials (VEMP), a widely-used laboratory test of otolith function.
  
  
  RESULTS
  The average vOCR for healthy controls (4.6°) was significantly different from UVL (2.7°) and BVL (1.6°) patients (p < 0.0001). The vOCR and VEMP measurements were correlated across subjects, especially the click and tap oVEMPs (click oVEMP R = 0.45, tap oVEMP R = 0.51; p < 0.0003). The receiver operator characteristic (ROC) analysis showed that vOCR and VEMPs detected loss of otolith function equally well. The best threshold for vOCR to detect vestibular loss was at 3°. The vOCR values from the side of vestibular loss and the healthy side were not different in UVL patients (2.53° vs 2.8°; p = 0.59).
authors.affiliation: a Department of Neurology , The Johns Hopkins Hospital , Baltimore , MD , USA.
authors.forename: Jorge
authors.initials: J
authors.lastname: Otero-Millan
authors.affiliation: b Department of Otolaryngology , University of Minnesota Medical Center , Minneapolis , MN , USA.
authors.forename: Carolina
authors.initials: C
authors.lastname: Treviño
authors.affiliation: a Department of Neurology , The Johns Hopkins Hospital , Baltimore , MD , USA.
authors.forename: Ariel
authors.initials: A
authors.lastname: Winnick
authors.affiliation: a Department of Neurology , The Johns Hopkins Hospital , Baltimore , MD , USA.|c Department of Otolaryngology , The Johns Hopkins Hospital , Baltimore , MD , USA.|d Department of Neuroscience , The Johns Hopkins Hospital , Baltimore , MD , USA.|e Department of Ophthalmology , The Johns Hopkins Hospital , Baltimore , MD , USA.
authors.forename: David S
authors.initials: DS
authors.lastname: Zee
authors.affiliation: c Department of Otolaryngology , The Johns Hopkins Hospital , Baltimore , MD , USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Carey
authors.affiliation: a Department of Neurology , The Johns Hopkins Hospital , Baltimore , MD , USA.|c Department of Otolaryngology , The Johns Hopkins Hospital , Baltimore , MD , USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Kheradmand
mesh_terms: D000328:Adult; D003939:Diagnostic Techniques, Otological / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015837:Vestibular Diseases / Q000175:diagnosis*; D058585:Vestibular Evoked Myogenic Potentials
keywords: OCR; VOG; clinical test; ocular counter-roll; otolith; vestibular; video-oculography