HINTS (Head Impulse Nystagmus Test of Skew) Exam

The HINTS "Plus" examination is used to evaluate patients with the acute vestibular syndrome (AVS), an acute onset of continuous vertigo or dizziness, nausea, and vomiting with nystagmus. A head impulse test is performed to evaluate function of cranial nerve 8. The patient is asked to look at a target (the examiner's nose) while their head is quickly thrust to either side. A positive test occurs when the patient's eyes fall off target followed by a quick correction (a catch up saccade), which represents peripheral vestibular dysfunction. Nystagmus that is unidirectional and mixed horizontal-torsional is considered peripheral. All other patterns of nystagmus as listed above are considered central findings. Test of skew is evaluated by completing the cross-cover test (occluding one eye and then the other). If there is a vertical movement after the eye is uncovered, this is called a skew deviation and is a central localizing finding. Lastly, in a patient with AVS, acute onset hearing loss should be considered a central sign until proven otherwise, unless there is an obvious explanation for the patient's symptoms. All components of the peripheral HINTS exam must be present for it to be considered a peripheral localizing examination.