Use of HINTS in the acute vestibular syndrome. An Overview

Abstract

Following the initial description of HINTS to diagnose acute vestibular syndrome (AVS) in 2009, there has been significant interest in the systematic evaluation of HINTs to diagnose stroke and other less common central causes of AVS. This trend increased with availability of the video head impulse test (video-HIT). This article reviews the original papers and discusses the main publications from 2009 to 2017. Many authors use video-HIT in the diagnosis of patients with AVS; this paper focuses on the major publications on the topic featuring nystagmus, manual and video-HIT, and skew deviation. Twenty-five papers provide a summary of the last 8 years' application of HINTS, the video-HIT added quantitative information to the early clinical observations. Further research will undoubtedly provide specific combination of abnormalities with high degree of lesion localisation and aetiology. In a short time following the original description, neurotologist and neurologists in the evaluation of AVS use the HINTS triad. The introduction of the video-HIT added greater understanding of the complex interaction between the primary vestibular afferents, brainstem and cerebellum. In addition, it permits evaluation of the angular vestibulo-ocular reflex in the plane of all six semicircular canals, with accurate peripheral versus central lesion localisation often corroborated by brain imaging.

Keywords: acute vestibular syndrome; dizziness; head impulse test; stroke; vertigo.

Figure 1

Axial DWI MRI. The top three panels represent serial images obtained when the patient was asymptomatic. The lower three panels obtained while symptomatic, about 10 hours later with primary gaze upbeat nystagmus and a right internuclear ophthalmoplegia. The red arrow points to the mid-basilar stenosis and occlusion of the lumen of a paramedian penetrator artery. The yellow arrow points to the midline pontine tegmentum/basis pontis stroke.