Benign Paroxysmal Positional Vertigo (BPPV)

As the name says, this condition brings sudden severe dizziness with movements of the head. Patients describe dizziness that starts as they bend down and straighten up, or as they turn from one side to the other in bed, and that lasts about 30 to 40 seconds.

The first attack frightens people badly. Patients think they are having a heart attack and that they are about to die.

What causes it

The inner ear balance organ holds crystals called otoconia in a part named the saccule. In BPPV these crystals break loose and fall into the semicircular canals.

Whichever canal the crystals fall into, movement of the head along that axis brings on violent dizziness. The canal affected most often is the posterior semicircular canal.

BPPV happens at every age, and it is commoner in older people. Over the age of 65 it is the commonest cause of dizziness.

How the doctor tests for it

The diagnosis is made with positional tests, in which the patient is put into specific positions. The one used most often is the Dix-Hallpike test.

The patient sits on a couch. The doctor turns the head to the right, then lays the patient down quickly while the head keeps that position, so that the head hangs slightly over the end of the couch. During this the doctor watches the patient’s eye movements through Frenzel glasses or with videonystagmography, and looks for the specific eye movement called nystagmus. The patient then sits up again, the head is turned the other way, and the test is repeated.

On the affected side, the position brings on nystagmus, which is a fast jerking movement of the eyes.

Treatment

The condition often settles by itself in a short time. In some patients it does not, and a doctor has to assess them.

The treatment used most often is a repositioning manoeuvre, which sends the crystals back where they belong. The Epley manoeuvre is used most for BPPV of the posterior canal. The barbecue manoeuvre is used most for BPPV of the lateral canal.

One manoeuvre cures 80 to 90 per cent of patients. A second or a third manoeuvre is sometimes needed, and with those 90 per cent of patients recover. Patients who do not respond do habituation exercises, and these solve most of the remaining cases.

Very rarely a patient does not improve with any of these treatments. Surgery is then considered. The surgeon can close the affected semicircular canal, or cut the balance nerve on the affected side.

It can come back

BPPV returns in one third of patients within the first year, and in at least half within five years. This is nothing to fear. It is usually treated with the same repositioning manoeuvres as the first time.