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

Vestibular neuritis

Vestibular neuritis, also called labyrinthitis or acute unilateral vestibulopathy, is a disorder characterised by sudden loss of function of the vestibular nerve on one side. It's usually acute, but almost always completely reversible. It's a common cause of vertigo and acute vestibular syndrome.

Etiology

As the name implies, vestibular neuritis is assumed to be secondary to inflammation. The prevailing theory is that it's caused by reactivation of latent herpes simplex virus or other viruses. Many patients (up to 40%) have a preceding viral URTI. However, there are few real data to support this mechanism. So the cause is not really well known.

Clinical features

Symptoms include sudden onset (acute or subacute) persistent vertigo, nausea/vomiting, intolerance to head movement, spontaneous nystagmus, and a tendence to fall to the diseased side. The vertigo lasts for multiple days. The nystagmus is directed toward the healthy ear. There is no hearing loss and no focal neurological features. There may be a history of viral URTI recently.

Diagnosis and evaluation

Vestibular neuritis is a clinical diagnosis. Performing the HINTS test is obligatory to rule out central causes of vertigo. As a peripheral cause of vertigo, vestibular neuritis is HINTS positive.

Management

Vestibular neuritis is self-limiting and harmless, but hospital admission may be necessary if one cannot rule out a posterior circulation stroke clinically or if the patient is so severely affected that they cannot function at home.

In the acute phase, bed rest and an antiemetic is indicated. After the condition improves, early vestibular rehabilitation (exercises to train the vestibular system) and movement is important to hasten recovery. A corticosteroid may hasten recovery, but it's unknown whether it improves long-term prognosis. A 10 day taper of prednisolone may be used.

Benign positional paroxysmal vertigo

Benign positional paroxysmal vertigo (BPPV) is a cause of recurring vertigo which occurs due to canalolithiasis, stones in the semicircular canals of the inner ear.

The peak incidence is in the 50s and it affects females more often.

There are two types, posterior canal BPPV (90% of cases) and horisontal canal BPPV (10%).

Clinical features

BPPV causes paroxysmal positional harmonic vestibular signs. Paroxysmal and positional meaning that the symptoms occur in suddenly in certain head positions. The symptoms include vertigo and nystagmus, and last less than 1 minute. In between these episodes, the patient is asymptomatic.

Diagnosis and evaluation

Diagnosis of posterior canal BPPV is based on the Dix-Hallpike test:

Procedure:
- Patient sits on the examination table
- Rotate the head 45 degrees to the side of the suspected BPPV
- Keeping the neck rotated, quickly lay the patient in a supine position so that their head hangs slightly off the short end of the table
- Hold this position for 20 seconds
- Slowly reposition patient into the original seated position
Negative:
- Patient experiences no vertigo
- No nystagmus appears
Positive:
- Patient experiences vertigo and nystagmus when supine, which spontaneously resolve within the 20 seconds

Diagnosis of horizontal canal BPPV is based on the supine roll test.

Treatment

Posterior canal BPPV is treated by the Epley repositioning manoeuvre. It moves the stone into the utricle and out of the semicircular canal. The manoueuvre may need to be repeated multiple times, and the patient may be taught the manoeuvre for performance at home.

Procedure:
- Patient sits on the examination table
- Rotate the head 45 degrees to the side of the suspected BPPV
- Keeping the neck rotated, quickly lay the patient in a supine position so that their head hangs slightly off the short end of the table
- Hold this position for 30 seconds, or until the nystagmus disappears
- Turn patient’s head by 90° towards the unaffected side
- Hold this position for 30 seconds, or until the nystagmus disappears
- Turn patient’s head another 90° towards the unaffected side, so that the patient is lying on their side with they head facing the ground
- Hold this position for 30 seconds, or until the nystagmus disappears
- Slowly bring patient back to a seated, upright position with the head in a neutral position
- Ask patient to remain in this position for about 15 minutes

Horisontal canal BPPV is treated by the barbecue manoeuvre.

Meniere disease

Meniere disease (idiopathic endolymphatic hydrops)
- Impaired resorption of endolymph causes accumulation
- Epidemiology
  - Females
  - Older adults
- Clinical features
  - Meniere triad
    - Episodes lasting from minutes to hours
    - 3 yes 1 no
    - Yes: Sensorineural HL
    - Yes: Repeated attacks of vertigo
    - Yes: Tinnitus
    - No: No neurological signs
- Diagnosis
  - Criteria
    - >1 episode that lasts 20 minutes to 12 hours
    - Low-mid frequency SN hearing loss
    - Tinnitus
- Treatment
  - Avoid triggers (stress, alcohol, caffeine)
  - Low sodium diet
  - Rehabilitation
  - Bed rest
  - Drugs
    - First generation antihistamines
    - Histamine analogues
    - Gentamycin in ear – destroy vestibule
  - Surgery
    - Labyrinthectomy
    - Sacculotomy
    - Vestibular neurectomy