Benign Paroxysmal Positional Vertigo (BPPV) is one of the most common causes of vertigo. BPPV stands for:
Benign as although it can be quite disabling, it is not due to serious disease
Paroxysmal because it occurs in short bursts of up to one minute
Positional as it is provoked specifically by movement to or from certain positions
Vertigo – dizziness defined as an illusion of movement.
Who is affected by BPPV?
BPPV is estimated to affect around 50% of all people at some time in their lives and can become progressively more common with age.
Symptoms of BPPV
The vertigo is generally rotational (like getting off a roundabout) but sometimes sufferers, on lying down, will feel that they are falling through the bottom of the bed or, on getting up, that they are being thrown back onto it. The classic provoking movements to induce BPPV are: lying flat, sitting up from lying flat; turning over in bed; looking up (e.g. hanging washing) or bending down, especially if also looking to the side. The duration of the vertigo is brief; usually five to 30 seconds but very occasionally lasts up to two minutes.
What causes BPPV?
BPPV is caused when loose chalk crystals get into the wrong part of the inner ear. These microscopic crystals should be embedded in a lump of jelly. The crystals weigh the jelly down and make that part of the ear sensitive to gravity. The crystals are constantly being re-absorbed and re-formed and over time fragments come loose. Lying flat can then occasionally cause some of the loose debris to fall into one of the semi-circular canals; the parts of the ear responsible for sensing rotation. Movement in the plane of the affected canal causes the crystals to move along the canal, stimulating it and giving the sensation of rotation.
How is BPPV diagnosed?
During periods when attacks are not occurring, the diagnosis is made from the characteristic history and by the exclusion of other disorders that can cause similar dizzy symptoms. When attacks are occurring, the Hallpike positional test is diagnostic. In the commonest form of BPPV the Hallpike test is positive (i.e. induces vertigo and nystagmus) when the affected ear is down most. Up to 10% of cases may involve both ears.
How is BPPV treated?
At least a half of all cases will get better without treatment though this may take months. As BPPV is basically a mechanical disorder, drugs have no effect and should be avoided. Most cases that do not resolve rapidly can now be relieved by the appropriate Particle Repositioning Manoeuvre; of which the most commonly performed is the Epley manoeuvre which offers instant relief of symptoms in nine out of 10 patients.