This sounds a bit like the punch line of a bad joke, doesn’t it? But believe it or not, it’s true.
Dizziness can be caused by loose crystals called “otoconia” in your inner ear, which is known as BPPV. Benign paroxysmal positional vertigo, or BPPV, is the most common cause of vertigo, and is also the most common vestibular (inner ear) disorder. BPPV occurs when tiny calcium crystals are displaced from either one or both of the otolith organs of the inner ear and fall down into one of the semicircular canals, disrupting the flow of the fluid of that canal.
What results from that disruption of fluid is essentially a false sense of motion. People with BPPV will most often report experiencing short episodes of severe vertigo with change in head and/or body position, such as turning over in bed or getting up and out of bed, tilting their head back in the shower to wash their hair, or turning their head from side to side while driving. The onset of vertigo can be very sudden and very frightening. And while the classic sign of BPPV is episodic severe vertigo related to changes in head position, many people experience a more mild or low grade constant unsteadiness between attacks or episodes.
Why do those crystals come loose?
About half of the time, the cause is unknown. When the reason can be identified, it is typically the result of a head injury, which can range from mild to severe. Sometimes taking a misstep off the end of a curb is enough to displace one or more otoconia. High intensity aerobics or mountain biking on rough trails can also cause BPPV. Occasionally, BPPV can be secondary to viruses that affect the inner ear, such as vestibular neuritis or labyrinthitis, and has also been associated with migraines.
How is BPPV diagnosed?
The diagnosis of BPPV is typically based on case history, physical examination, possibly hearing and vestibular testing or lab work to rule out other diagnoses, and the Dix-Hallpike maneuver which is designed to elicit nystagmus (eye beating) as a result of specific changes in head positions. The involved semicircular canal is revealed through the pattern of nystagmus elicited in the Dix-Hallpike maneuver.
How is BPPV treated?
While BPPV is the most common cause of vertigo, it is also one of the most easily treated. Repositioning maneuvers are completed typically in a health care provider’s office but can sometimes be performed at home as well. The maneuvers incorporate a specific series of head and body movements designed to move the displaced otoconia out of the involved or affected semicircular canal. This series of movements is typically completed in a short period of time, though repetition of the series can sometimes be required. There are several types of repositioning maneuvers, including the Epley maneuver, the Semont, and the Appiani, which are specific to the semicircular canal that is involved.
(You can also find more information on BPPV here.)