BPPV Statistics
Benign Paroxysmal Positional Vertigo is the most common cause of dizziness, most experts agree. Experts disagree as to its prevalence, however, if anyone you know has gotten dizzy briefly from leaning back, rolling over, or simply changing head position, they probably have BPPV.
Patients often come in having been told that they 'have rocks loose in their head' or 'crystals' loose in their balance system. This is correct. It just isn't correct in the sense most patients imagine. The rocks or crystals are actually otoconia. Otoconia are calcium carbonate crystals that are normally a part of the otolithic membrane included in one of the five vestibular (inner ear balance organs) organs called the utricle.
The otolithic membrane and the otoconia are gravity sensors. When they sit on the otolithic membrane, the inner is given accurate information in regard to movement up and down and sideways. In the case of injury, a disease process, or in the case of degeneration, the otolithic crystals break off of the utricle.
Once free of the utricle, the otoconia still manage to create sensations of the pull of gravity only that once they are free-floating in the inner ear balance system they no longer provide accurate information. In most cases, the physiology of the inner ear balance system has these crystals ending up in what is commonly referred to the posterior semicircular canal. When the crystals end up in the posterior semicircular canal, dizziness will be provoked by having a patient lean their head backwards and turn either right or left. The dizziness will depend on where the crystal have ended up. If they are free on the right side, the dizziness will occur when the leaning and turning goes to the right. If the otoconia are loose on the left, then leaning back and turning to the left will produce dizziness. We test for BPPV by leaning patients backwards and having them turn their heads - commonly called a Dix-Hallpike test. If you get dizzy the test is positive, if you don't get dizzy, the test is negative.
Once the position of the crystals has been identified, they can often be repositioned into their proper place. The most common and famous of these repositioning maneuvers is called the Epley Maneuver. After one, sometimes several, Epley maneuvers, the condition is greatly improved as measured by putting the patient's head into the offending position and checking for dizziness.
It is commonly suspected that BPPV is a symptom rather than a disease process. We are the Werner Center certainly believe so. The otoconia don't just randomly come off. There is an insult, injury, or process at work. We use as evidence that a great majority of our BPPV patients exhibit inner ear weakness and dysfunction on other measures of balance such as the VNG, the VAT, and the CDP. These issues need to be addressed as well to keep patients functioning optimally.
BPPV recurs in a good number of patients. So, maintaining a relationship with your therapist who can work you into their schedule when you are having an episode of BPPV is a very good idea.
