Vertigo
Vertigo is the sensation that you are moving, or everything moves around you. It's a common symptom in a variety of disorders, ranging from harmless to life-threatening.
Acute vestibular syndrome is defined as the presence of severe vertigo lasting more than 24 hours which causes nausea and vomiting and an intolerance to head movement (because it makes the vertigo worse).
Etiology
The most common causes include:
- Non-ENT causes
- Orthostatic hypotension
- Hypertension
- Heart disease
- Anaemia
- Peripheral causes
- Vestibular neuritis (most common)
- Benign positional paroxysmal vertigo
- Central causes
- Posterior circulation stroke or TIA
- Vestibular migraine
Types
One can distinguish two types of vertigo:
- Peripheral vertigo
- Central vertigo
Peripheral vertigo is the most common and is caused by dysfunction of the vestibular system. Central vertigo is rare but can be fatal, and is due to disorder of the CNS. In Hungarian literature, these are called harmonic and disharmonic vestibular syndromes, respectively.
Clinical features
Nystagmus, nausea, and vomiting are all common features in people with vertigo. In case of focal neurological signs, posterior circulation stroke is likely. In case of tinnitus or hearing loss, peripheral causes are more likely.
Peripheral vertigo (harmonic vestibular syndrome) | Central vertigo (disharmonic vestibular syndrome) | |
---|---|---|
Nystagmus direction | Never changes direction
Fast component away from affected ear. (Slow component toward affected ear) |
Direction may change based on gaze
Fast component toward affected side. (Slow component away from affected ear) |
Nystagmus type | Horizontal or combined horizontal and rotational
Never purely rotational or purely vertical |
Any direction
Purely vertical or purely rotational is always central |
Sense of motion | Severe, nausea and vomiting common | Usually mild |
Romberg test | Patient falls toward the affected ear | Patient falls toward the affected side |
Does visual fixation suppress nystagmus? | Yes | No |
Postural instability | Instability toward affected side
Walking usually preserved |
Severe instability
Walking usually difficult |
Other inner ear symptoms (hearing loss, tinnitus) | May be present | Usually not present |
Ataxia, diplopia, dysphagia, weakness, other neurological symptoms | Absent | Often present |
Diagnosis and evaluation
HINTS
The HINTS exam is essential for screening for posterior circulation stroke in patients presenting with acute-onset sustained vertigo (not episodic or paroxysmal vertigo). The name is a mnemonic for three tests. The patient must have vertigo during the examination for it to be valid.
Head Impulse test
The head impulse test is performed by asking the patient to fixate on your nose. The examiner gently turns the patient's head 30 degrees to the side, and then rapidly turns the head back so the patient faces forward again. This is repeated to both side.
If there is no dysfunction of the peripheral vestibular system (negative test), the vestibulo-ocular reflex ensures that the examinee will be able to fixate their eyes on the examiner's nose despite the head movements.
If there is dysfunction of the peripheral vestibular system (positive test), the vestibulo-ocular reflex is lost. This causes the examinee to lose fixation on the examiner's nose for a second after the rapid head turn (the eyes move with the head), before the eyes rapidly move to fixate on the nose again.
Nystagmus
Ask the patient to look to the left. Look for nystagmus. Then do the same for the other side.
If there is no dysfunction of the peripheral vestibular system (negative test), the nystagmus will change direction when the patient changes their gaze. In other words, if the nystagmus beats to the left when looking left, it will change to beating right when the patient looks right.
If there is dysfunction of the peripheral vestibular system (positive test), the nystagmus will maintain the same direction irrespective of the direction of gaze.
Test of skew
Ask the examinee to focus their gaze on the examiner's nose. The examiner must cover one of the examinee's eyes, then quickly move the cover to the other eye. Observe for uncovered eye for vertical movement. Repeat for the other side.
If there is no dysfunction of the peripheral vestibular system (negative test), the eye from which the cover was moved will exhibit a vertical movement.
If there is dysfunction of the peripheral vestibular system (positive test), there will be no such vertical movement.
Interpretation of HINTS
If the head impulse test, nystagmus test, and test of skew are ALL positive, and there are no focal neurological signs, then a peripheral cause of vertigo is more likely.
If ANY of the tests are negative, or if there are any focal neurologal signs, then posterior circulation stroke is more likely, and the patient requires neuroimaging for stroke.
Differential diagnosis
Peripheral vertigo
Disorder | Duration of episode | Recurrence of vertigo | Other symptoms | Other clinical features |
---|---|---|---|---|
Vestibular neuritis | Days | Single episode | Symptoms of viral infection earlier or during. Intolerance to head movement, spontaneous nystagmus, and a tendence to fall to the diseased side | None |
Benign paroxysmal positional vertigo | Seconds | Recurrent episodes | Specific head movements and positions precipitate symptoms | Positive Dix-Hallpike test |
Ménière disease | Hours | Recurrent episodes | Hearing loss, tinnitus | Audiometry shows SN hearing loss |
Otitis media | Days | Single episode | Ear pain | Characteristic findings on otoscopy |
Central vertigo
Disorder | Duration of episode | Recurrence of vertigo | Other symptoms | Other clinical features |
---|---|---|---|---|
Vestibular migraine | Minutes | Recurrent episodes | Headache, other symptoms of migraine | None |
TIA of vertebrobasilar system | Minutes | Single or multiple episodes | Other brainstem or cerebellar symptoms | MRI confirms ischaemia |
Brainstem stroke | Days | Single episode | Other brainstem symptoms | MRI confirms infarct |
Cerebellar stroke | Days | Single episode | Other cerebellar symptoms | MRI confirms infarct |