Measurement of HINTS in peripheral vestibulopathy
Reviewed by Praneta Kulloo

Acute vestibular syndrome (AVS) is caused by acute onset of unilateral vestibular insult in either the peripheral or central vestibular system. The HINTS (head-impulse, nystagmus, test-of-skew) exam is a bedside test to distinguish central lesions among patients with AVS. In a patient with stroke, positive findings of HINTS are presence of normal head-impulse test (HIT), direction-changing nystagmus in eccentric gaze and skew deviation. The authors conducted a study to evaluate how often the central sign, a positive HINTS finding, appeared in patients with acute peripheral vestibulopathy showing spontaneous nystagmus. They included 14 acute vertigo patients with spontaneous nystagmus in their outpatient clinic over a one-year period. Horizontal vestibulo-ocular reflex (VOR) gain was measured using the video head-impulse test (vHIT). Gaze-evoked nystagmus (GEN) was evaluated from values of slow-phase velocities at different points of lateral gaze. Skew deviation was tested using anaglyph goggles simulating the alternate cover test. Diagnoses of the 14 subjects were vestibular neuritis (seven, 50%), Ménière’s disease (five, 36%), acute spontaneous vertigo with spontaneous resolution (one, 7%), and vestibular schwannoma (one, 7%). Among the 13 patients of peripheral vestibulopathy, seven showed positive signs in HINTS (normal vHIT and skew deviation). The patient with vestibular schwannoma had positive HINTS findings. This study suggests that there are cases with positive HINTS findings in acute vertigo patients with peripheral lesions. The authors recognise that their study is underpowered with a small sample size and their results may not be generalisable to other patients. It is not possible to conclude a central cause in patients with dizziness based only on HINTS measurements. Instead, comprehensive evaluation including medical history and other factors, such as stroke risk, is more important when evaluating AVS patients. Larger studies are required to establish how quantitative HINTS tests may become clinically useful.

Objective measurement of HINTS (Head Impulse, Nystagmus, Test of Skew) in peripheral vestibulopathy.
Lee DH, Schneider E, Lee SY, et al.
AURIS NASUS LARYNX
2022;49(6):938-49.