Your Audiology Tutorial: BPPV

It's a horrible effect. You're turning your head or entire body while in bed and the room tilts. Worse yet, does 360s. Maybe it occurs when you make such a turn while showering, or driving. The episode usually only lasts a minute or so, leaving you dazed, possibly nauseous, very likely confused and alarmed. For some, it's akin to being spun around in a swivel chair (or the Mad Hatter's Tea Cup ride at Disney World). The after effect? You feel like the floor is coming up to smack the side of your head.

If that's you, you may have suffered Benign Paroxsymal Positioning Vertigo (BPPV). Well documented in medical lit and coffee table mags alike, BPPV accounts for about half of all reported dizziness. It is the most common vertiginous disorder seen by ear, nose, and throat (ENT) doctors. Children may get it, but it is more likely to occur, the older you are.

Calcium crystals, known as otoconia, are naturally occuring in the inner ear. However, due to head traumas, infections, or advancing age, these "ear rocks" migrate into the fluid filled area that, by its movement, transfers information that will travel up the hearing/balance nerve to the brain. When the fluid moves, messages are sent to Central, so to speak. If this debris is falling into and moving around in that fluid, like stones skipping across a pond, the ripples will tell the brain you are moving when you may not be. Those quick head turns set the rocks in motion after they've fallen into a free float. They also may attch themselves to the canals, making treatment/management more challenging.

How is BPPV diagnoed? The clinician (audiologist, ENT, etc.) will perform a maneuver, bringing the patient supine and head to either side. Such a positioning, if the patient is positive for BPPV, will provoke an involuntary, often torsional eye movement known as nystagmus.

The patient will also note (sometimes quite loudly and with great anxiety) that the room is spinning. The sensations usually come on quickly, intensely, then subside in under a minute. The clinician may repeat the procedure (known as the Dix-Hallpike maneuver) to see if the wild eye movement and subjective complaint fatigues with the do-over. If so, you have classic symtomology.

How is BPPV treated? A repositioning of the head is performed, most commonly known as the Epley Manuever. Basically, the patient gets another Dix-Hallpike, with the problem ear down (BPPV is usually unilateral). The tester waits for the nystagmus. Then, three more movements of the head and body are performed in an effort to get the errant crystals out of where they don't belong. It is a quick, easy procedure that boasts an 80% effective cure rate. It can be performed by the above professionals or a physical therapist. Recurrance rate is low, but sometimes a repeat of the Epley is required a week later or later in life. Some patients are prescribed a protocol of home exercises for self-treatment as well.

More invasive surgical procedures are sometimes utilized, such as a Posterior Canal Occlusion. The surgeon actually plugs the fluid filled area of a particular inner ear canal so the message (via the moving fluids) stops prior to reaching the nerve. A small risk to hearing is posed if this procedure is undertaken. Fortunately, it is rarely needed, as most patients have spontaneous remission.



Here's a glimpse at what nystagmus during a BPPV episode looks like:

http://video.google.com/videoplay?docid=164170967551063153&ei=GW78SrmbJJOerAK007GrBA&q=BPPV+nystagmus&hl=en#

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