Diagnostic value of video Head Impulse Test

Abstract

The head impulse test (HIT) is a safe and quick way of assessing at the bedside semicircular canal function in patients with peripheral vestibular loss, first described in 1988. This test is practical even in sick patients and needs no equipment. The clinician identifies overt (visible) catch-up saccades back to the target after passive head rotation as a clinical sign of canal paresis. However, it is known that some patients with absence of vestibular function do not make overt saccades, but instead make covert catch-up saccades during a passive unpredictable head turn, which are extremely difficult for the clinician to detect with the naked eye. In 2009, a new lightweight, nonslip, high-speed video-oculography system (vHIT; video head impulse test) was developed, that measures eye velocity during head rotations. This system is easy to use in a clinical setting, provides an objective measure of the vestibuloocular-reflex (VOR), and detects both overt and covert catch-up saccades in patients with vestibular loss. This article discusses the diagnostic values of vHIT which can evaluate both horizontal and vertical semicircular canal functions in patients with a variety of vestibular diseases.

The Clinical Key Features of Persistent Postural Perceptual Dizziness in the General Medicine Outpatient Setting: A Case Series Study of 33 Patients

“…However, there is a possibility that BPPV could not be completely excluded because we could not check the positional nystagmus testing and supine positional testing using a CCD camera with infrared illumination over Frenzel glasses at the time that PPPD was diagnosed ( 15 , 16 ). In addition, vestibular dysfunction cannot be completely excluded because we could not check the quantifiable video-head impulse test or caloric test by at the time of diagnosis of PPPD ( 17 , 18 ). Third, the telephone interviews used to determine outcomes had a response rate of 78.8%, and it is possible that there was some sampling bias for the treatment outcomes.…”