Using the clinical exam to evaluate the vertigo patient

xx

Dizzy17

Once you understand how inner ear disease can cause vertigo and nystagmus, you can use our simple four step clinical scheme to distinguish inner ear problems from more serious and rarer central causes like stroke in dizzy patients:

xx

Step one, does this dizzy patient have vertigo?

First, be sure you understand what the patient means by dizziness – patients can use this vague term when they as suffering from:

xx
Lightheadedness or pre-syncope from an impending faint:

xx

Disequilibrium or unsteady gait:

xx

True vertigo, which is a definite sense (hallucination) of movement, using a spinning:

xx

Once you have diagnosed vertigo, you need to find out if you are dealing with:

1. An acute prolonged episode of vertigo (go to step two),

2. Recurrent episodic vertigo (go to step three), or

3. Chronic dizziness (go to step four).

xx

For acute prolonged vertigo, Step two is used to distinguish an acute labyrnthitis from something more sinister like a brain stem or cerebellar stroke.

Labyrinthitis is acute unilateral labyrinthine failure caused by viral or post-viral inflammation of the inner ear. This causes the acute onset of vertigo, nausea, and vomiting, worse with movement, better sitting or lying still. Physical exam will show a characteristic peripheral nystagmus.  In the case shown below, the nystagmus is right beating (the fast phase is to the right) and it gets worse on gaze to the right-side, indicating left labyrinthine failure:

Patients can use visual fixation to suppress the vertigo – so it’s worse with the eyes closed, and recovers spontaneously within a few days from central compensation.

xx
However, even though the vertigo and nystagmus are suppressed, patients will still have a positive head thrust test, which is a useful sign for diagnosing peripheral vertigo in the emergency room.

xx
A normal patient can maintain visual fixation when the head is quickly rotated to one side:

xx
When a patient has labyrinthitis (and unilateral labyrinthine failure) undergoes the head thrust test, their eyes cannot keep up when the head is thrust to the bad side, and what you see is a delayed catch up saccade to maintain fixation:Dizzy6

xx

xx
By contrast, acute central vertigo is rarer and more serious, usually caused by brain stem or cerebellar stroke:
Dizzy8
Central nystagmus doesn’t fatigue (compensate) and is associated with other signs like ataxia (dysmetria or past pointing):

Unlike peripheral nystagmus, central nystagmus can occur in any direction, even vertically:

Here is a summary of how to differentiate peripheral from central nystagmus:
Dizzy11

Obviously, if you can correctly complete step two, and confidently diagnose a peripheral problem, you can potentially avoid an necessary brain scan. Only the patients with suspected central lesions need to undergo costly brain imaging and admission to the hospital.

xx

Step three is to evaluate patients presenting with recurrent episodes of vertigo.

This is best classified according to the duration of each episode.

Most of these patients will be having brief episodes of vertigo and/or dysequilibrium triggered by certain head movements.  This is usually going to be from benign paroxysmal positional vertigo. Click here to find out more how to diagnose and treat this common disorder.

Dizzy18

xx

Patients with vertigo episodes lasting for hours are usually going to turn out to have migrainous vertigo, particularly if the episodes are associated with headache.

Dizzy19

xx

Finally, patients with recurrent vertigo attacks lasting days,  particularly when associated with pressure or fullness in the ears and or tinnitus, are likely to be suffering from Meniere’s disease.  Now, you might get fooled into thinking this is a labyrinthitis during their first attack, but once they have their second or third episode this common syndrome becomes easier to diagnose.

Meniere’s disease, sometimes referred to as endolymphatic hydrops, is caused by the episodic built up of fluid pressure in the inner ear:

Dizzy20

Meniere’s disease is caused by episodes of increased fluid pressure within the inner ear (right), alternating with times when there is more normal fluid pressure (left).

During the episode of pressure build up, the affected patient will experience a prolonged episode of vertigo, nausea and dysequibrium, usually associated with a sense of pressure and tinnitus  in the affected ear.  The audiogram will show low frequency hearing loss during the attack, which normalizes between attacks, and demonstrating this fluctuating hearing loss is the best way to make the diagnosis:

dizzy13

Audiograms from a patient with Meniere’s disease, showing a normal pattern when asymptomatic (left) and a low frequency hearing loss during an attack (right).

Some patients with Meniere’s disease will also develop otolithic drop attacks, when they suddenly drop down to one side without loss of consciousness.  They will often say that they felt themselves being pushed over:

xx

Finally, Step four, the patient with chronic dizziness:

These are patients who complain of chronic unsteadiness and dizziness most days for >2 months. Symptoms are most severe standing and walking. Many patients have associated anxiety and depression. This syndrome can be provoked by an inciting event like a labyrnthitis (25%), BPPV or vestibular migraine, and the syndrome might be the result of a failure of central compensation or adaptation:
Dizzy16
xx

So, next time you see a dizzy patient, try it out…..

Using this scheme to correctly diagnosis will not only help you patient get better more quickly, but also save the expense of unnecessary brain scan and hospital admission – this can add up to billions of $$s!

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s