I. See Also
- HiNTs Exam (Three-Step Bedside Oculomotor Examination)
- Nystagmus
- Skew Deviation (Vertical Ocular Misalignment, Vertical Heterotropia, Vertical Strabismus)
- Dix-Hallpike Maneuver
- Vertigo
- Vertigo Causes
- Peripheral Causes of Vertigo
- Central Causes of Vertigo
- Vertigo Diagnostic Testing
- Vertigo Management
- Meniere's Disease
- Motion Sickness
- Vestibular Neuronitis
- Benign Paroxysmal Positional Vertigo
- Perilymphatic Fistula (Hennebert's Sign)
- Acute Labyrinthitis
- Bacterial Labyrinthitis (Acute Suppurative Labyrinthitis)
- Dizziness
- Dysequilibrium
- Syncope
- Light Headedness
II. Indications
- Acute Vestibular Syndrome (AVS) evaluation
- Distinguishes Acute Peripheral Vestibulopathy (APV) in which there are catch-up saccades from cerebellar stroke in which saccades are absent
III. Mechanism
- Vestibulo-ocular reflex function test
- Peripheral Vertigo disrupts the Medial Longitudinal Fasciculus (communication between the vestibular system and Oculomotor Nucleus)
- Therefore a catch-up saccade is present due to a delay in the eyes needing to correct for the head position change
- In a posterior CVA, the defect is at a higher level and the eye correction is immediate (no saccade is seen)
IV. Technique
- Examiner asks the patient to focus on the examiners nose throughout the procedure
- Examiner rapidly rotates a patients head 20-40 degrees to the right or left
- Patients eyes are observed for Nystagmus
- Observe for one eye that lags in response to maintain forward gaze (makes quick saccade movement to catch-up or correct)
- Procedure is repeated several times on each side
- Avoiding habituation
- In between rapid movements, examiner gently and slowly rotates the patient's head from side to side
- Procedure is repeated multiple times, randomly selecting one side or the other, so the patient cannot anticipate which side will be tested next
V. Interpretation
- Acute Vestibular Syndrome (AVS) with a "normal" test (no saccade/correction) strongly suggests central Vertigo (e.g. cerebellar infarction)
- Acute Vestibular Syndrome (AVS) with an "abnormal" test (saccade/correction) weakly suggests Acute Peripheral Vestibulopathy (APV)
VI. Efficacy
- High Test Specificity for central Vertigo (low False Positive Rate)
- Strongly suggests central Vertigo (e.g. posterior CVA)
- Test is most valuable when "normal" (no saccade/correction) despite an Acute Vestibular Syndrome (AVS)
-
Test Sensitivity for central Vertigo: 85%
- Saccade present despite central Vertigo in 15% of cases (False Negative Rate)
- Presence of a saccade does not exclude central Vertigo
VII. Resources
- Video of a Head Impulse Test with saccades present
