title: Quantifying the vestibulo-ocular reflex with video-oculography: nature and frequency of artifacts.
abstract: Video-oculography devices are now used to quantify the vestibulo-ocular reflex (VOR) at the bedside using the head impulse test (HIT). Little is known about the impact of disruptive phenomena (e.g. corrective saccades, nystagmus, fixation losses, eye-blink artifacts) on quantitative VOR assessment in acute vertigo. This study systematically characterized the frequency, nature, and impact of artifacts on HIT VOR measures. From a prospective study of 26 patients with acute vestibular syndrome (16 vestibular neuritis, 10 stroke), we classified findings using a structured coding manual. Of 1,358 individual HIT traces, 72% had abnormal disruptive saccades, 44% had at least one artifact, and 42% were uninterpretable. Physicians using quantitative recording devices to measure head impulse VOR responses for clinical diagnosis should be aware of the potential impact of disruptive eye movements and measurement artifacts.
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors.forename: Georgios
authors.initials: G
authors.lastname: Mantokoudis
authors.forename: Ali S
authors.initials: AS
authors.lastname: Saber Tehrani
authors.forename: Jorge C
authors.initials: JC
authors.lastname: Kattah
authors.forename: Karin
authors.initials: K
authors.lastname: Eibenberger
authors.forename: Cynthia I
authors.initials: CI
authors.lastname: Guede
authors.forename: David S
authors.initials: DS
authors.lastname: Zee
authors.forename: David E
authors.initials: DE
authors.lastname: Newman-Toker
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D003430:Cross-Sectional Studies; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D064087:Head Impulse Test; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology*; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology; D020338:Vestibular Neuronitis / Q000175:diagnosis* / Q000503:physiopathology