Template:HINTS Exam Procedure: Difference between revisions
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====Inclusion Criteria==== | ====Inclusion Criteria==== | ||
*HINTS exam should only be used in patient with acute persistent vertigo, nystagmus, and a normal neurological exam. | *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:==== | ====The 3 components of the HINTS exam include:==== | ||
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''Test of vestibulo-ocular reflex function'' | ''Test of vestibulo-ocular reflex function'' | ||
#Have patient fix their eyes on your nose | #Have patient fix their eyes on your nose | ||
#Move their head in the horizontal plane to the left and right | #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 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 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> | #*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 | #*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 | #**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==== | ====Nystagmus==== | ||
#Observation for '''nystagmus''' in primary, right, and left gaze | #Observation for '''nystagmus''' in primary, right, and left gaze | ||
#*No nystagmus (normal) or only horizontal unilateral nystagmus is reassuring | #*No nystagmus (normal) or only horizontal unilateral nystagmus (fast direction only in one direction) is reassuring | ||
#*Any other type of nystagmus is abnormal, including bidirectional nystagmus | #*Any other type of nystagmus is abnormal, including vertical or bidirectional nystagmus | ||
====Test of Skew==== | ====Test of Skew==== | ||
Revision as of 16:54, 8 October 2023
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:
| HINTS Test | Reassuring Finding |
| Head Impulse Test | Abnormal (corrective saccade) |
| Nystagmus | Unidirectional, horizontal |
| Test of Skew | No skew deviation |
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 [1][2]
- 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