What is benign paroxysmal positional vertigo BPPV?

Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of dizziness and one of the easiest to diagnose and treat. It is best characterized by true vertigo and geotropic rotary nystagmus that occurs for a few seconds after specific head movements, such as rolling over in bed, bending over, or looking up. The vertigo usually lasts no more than a minute. Both the vertigo and nystagmus tend to lessen in severity with repetitions of the evoking movement. The symptoms are most often experienced when patients lie down, which distinguishes BPPV from orthostatic hypotension. BPPV may be recurrent.

What is the pathophysiology of BPPV?

It is thought that the most probable cause of BPPV is the dislodging of otoconia (calcium particles) that are shed from the utricular macula (which responds to linear motion) and migrate to the posterior semi-circular canal (which responds to rotational motion). These loose otoconia stimulate the nerve endings in the balance canals and send a message to your brain that you are moving in a direction you really are not. Whiplash injury, falls, a severe cold or even high-impact exercises may accelerate this process. Individuals with prolonged inactivity, such as confinement to a bed, may also develop BPPV because of the settling of the otoconia particles

When the otoconia particles have dislodged, they either settle into the sensory organ cupula of the posterior semi-circular canal (cupulolithiasis) or they may continue to free float within the endolymph of the posterior canal itself (canalithiasis). In either case, their presence sends misinformation about your position with respects to head movement, causing vertigo.

How is BPPV diagnosed?

The diagnosis of BPPV is determined by a clinical history, with a typical complaint of vertigo whenever the patient leans forward, sits up, or rolls over in bed. The diagnosis is confirmed by a positive response on the Dix-Hallpike maneuver, which will be discussed in the next section.

Following the first CRP procedure, more than 80% of patients no longer experience vertigo or nystagmus. Patients who do not respond to the first CRP and undergo a second or third procedure have an overall success rate of greater than 90%.

BPPV is not associated with any particular pattern of hearing loss.

What is the Dix-Hallpike test?

The Dix-Hallpike test is specific for the diagnosis of BPPV. While sitting on an examining table, the patient's head is turned either to the right or to the left. The patient is then moved rapidly from a sitting position to a supine position with the head hanging off of the back of the examining table. The patient is instructed to keep his/her eyes open so that the examiner can see eye movement during the entire procedure. If BPPV is present, vertigo will begin after a latency of 5 to 10 seconds and usually will last 30 seconds to a minute. Rotary nystagmus will occur and the patient will complain of dizziness. After the nystagmus and the vertigo subside, the patient is returned to the sitting position. The opposite ear is then tested in a similar fashion. The offending ear is the one that is toward the ground when BPPV occurs during the Dix-Hallpike maneuver.

How is BPPV treated?

The Canalith Repositioning Procedure (CRP) is the treatment of choice for patients with the classic signs of BPPV. Also known as the Epley maneuver, the patient is moved through several positions to slowly move the otoconia particles from the posterior semicircular canal back into the utricle. The entire CRP maneuver takes approximately 5 minutes. The patient is instructed not bend down or lay flat for 48 hours after the procedure. Two weeks after the CRP, the Dix-Hallpike test is repeated. Most patients are not symptomatic and the Dix-Hallpike maneuver elicits neither nystagmus nor vertigo. If the patient does experience vertigo and nystagmus, then the CRP is repeated.

Other than this post-procedure inconvenience, there is minimal stress to the patient. For patients who fail to improve with CRP, the possibility of positional vertigo has been eliminated and the diagnosis of a concomitant vestibular problem must be considered. Because long-term follow up is not required, there is no medication, and perhaps only two restless nights from sitting upright, CRP offers the most effective and tolerable treatment for BPPV.