View source for Template:HINTS Exam Procedure

====Inclusion Criteria====
*HINTS exam should only be used in patient with acute persistent vertigo, nystagmus, and a normal neurological exam. 
*HINTS exam, when done correctly, has high sensitivity and specificity in distinguishing peripheral vs central etiologies of vertigo
*Note that the original study was done by neuro-ophthalmologists in a differentiated patient base. This exam has not been studied in a large ED population yet

====The 3 components of the HINTS exam include:====
{| {{table}}
| align="center" style="background:#f0f0f0;"|'''HINTS Test'''
| align="center" style="background:#f0f0f0;"|'''Reassuring Finding'''
|-
| Head Impulse Test||Abnormal (corrective saccade)
|-
| Nystagmus||Unidirectional, horizontal
|-
| Test of Skew||No skew deviation
|}

*Always use correct terminology; "HINTS negative" does not convey a clear interpretation. State "HINTS central" or "HINTS peripheral" as suggested in literature
**If able, specify the exact exam finding as shown by chart above

====Head Impulse Test====
''Test of vestibulo-ocular reflex function''
#Have patient fix their eyes on your nose
#Move their head rapidly in the horizontal plane to the left and right
#*When the head is turned towards the normal side, the vestibular ocular reflex remains intact and eyes continue to fixate on the visual target
#*When the head is turned towards the affected side, the vestibular ocular reflex fails and the eyes make a visible corrective saccade to re-fixate on the visual target <ref>Barraclough K, Bronstein A. Vertigo. BMJ. 2009;339:b3493</ref><ref>Kuo CH, Pang L, Chang R. Vertigo - part 1 - assessment in general practice. Aust Fam Physician. 2008;37(5):341-7</ref>
#*Normally, a functional vestibular system will identify any movement of the head position and instantaneously correct eye movement accordingly so that the center of the vision remains on a target. 
#**This reflex fails in peripheral causes of vertigo affecting the vestibulocochlear nerve unilaterally; thus, failure of the reflex unilaterally is reassuring (since the cause is peripheral)
#*Note that in central causes of vertigo, test may show normal reflex response OR failure of the reflex BILATERALLY

====Nystagmus====
#Observation for '''nystagmus''' in primary, right, and left gaze
#*No nystagmus (normal) or only horizontal unilateral nystagmus (fast direction only in one direction) is reassuring
#*Any other type of nystagmus is abnormal, including vertical or bidirectional nystagmus

====Test of Skew====
#Have patient look at your nose with their eyes and then cover one eye
#Then rapidly uncover the eye and quickly look to see if the eye moves to re-align.  
#Repeat with on each eye
#*Skew deviation is a fairly specific predictor of brainstem involvement in patients with acute vestibular syndrome. The presence of skew may help identify stroke when a positive head impulse test falsely suggests a peripheral lesion.
#*Skew is also known vertical dysconjugate gaze and is a sign of a central lesion