Execution
- 1Position the patient sitting and ask the patient to fixate on the examiner's nose or a stationary target.
- 2Hold the patient's head and flex it slightly forward about 20° to 30°.
- 3Deliver a small, rapid, unpredictable head impulse to one side while keeping amplitude low.
- 4Observe whether the eyes remain on target or require a corrective saccade.
- 5Repeat several impulses to both sides and compare responses.
Positive outcome
A corrective catch-up saccade after a rapid head impulse indicates impaired vestibulo-ocular reflex on the side toward which the head was turned. A normal head impulse in a patient with continuous acute vertigo can be a central red flag when combined with direction-changing nystagmus or skew. Bedside HIT is less sensitive for mild or compensated vestibular hypofunction than video HIT.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Halmagyi & Curthoys (1988) | seminal clinical sign report | NA | NA | NA | NA |
| Black et al. (2005) | active versus passive head impulse study | NA | NA | NA | NA |
CommentHead impulse is a first-line vestibular hypofunction screen, but interpretation differs in chronic peripheral hypofunction versus acute vestibular syndrome. In HINTS, an abnormal HIT supports peripheral vestibular neuritis, while a normal HIT during continuous acute vertigo raises central concern. Video HIT is more objective than bedside observation.
Moderate Clinical Value