Vertigo – the sensation of movement where the individual or the individual’s surroundings appear to whirl about – is, for most people an unpleasant event. The sensations of vertigo sometimes include dizziness, falling or spinning. Any time vertigo affects balance, it may lead to falls and accidental injuries – especially in the elderly. More severe cases of vertigo can also cause vomiting, nausea, migraine headaches, visual irregularities called nystagmus and fainting spells.
There are several different forms of vertigo with different underlying causes. Audiologists generally encounter benign paroxysmal positional vertigo, or BPPV, because it’s related to your sense of hearing. Benign paroxysmal positional vertigo is caused by naturally-forming calcium crystals in the inner ear called otoconia or otoliths, and which normally cause no problems. In people who suffer from BPPV, however, these crystals become dislodged from their normal position and migrate into one of the semicircular canals of the inner ear that control our sense of balance. When a person with benign paroxysmal positional vertigo reorients their head relative to gravity, these crystals cause an abnormal displacement of endolymph fluid and cause vertigo.
BPPV is characterized by the episodic (paroxysmal) nature of the episodes, and may be triggered by such basic movements as looking up or down, tilting the head, rolling over while laying down, or any other sudden head motion. The ensuing vertigo can be worsened by stress, sleep disorders, or changes in barometric pressure (for instance, in advance of a rainfall or snowfall). BPPV may appear at any age, but it is most often seen in individuals over the age of 60. It is difficult to pinpoint the specific cause of benign paroxysmal positional vertigo for any given patient, but it generally develops after accidents in which the individual receives a blow to the head.
Benign paroxysmal positional vertigo is easily distinguished from other types of vertigo because it is almost always brought on by movements of the head with symptoms subsiding in one minute or less. Doctors may diagnose it by having the patient lie on their back and then tip their head to one side or over the edge of the examination table. More extensive tests can be used in certain cases including electronystagmography (ENG), videonystagmography (VNG) and magnetic resonance imaging (MRI). ENG and VNG test for abnormal eye movements while MRI is used to rule out other potential causes of vertigo such as brain abnormalities or tumors.
Benign paroxysmal positional vertigo is typically treated using a technique called canalith repositioning which guides the crystals to a position in the inner ear where there are less bothersome using a sequence of physical motions. Two types of canalith repositioning that may be used are the Epley maneuver and the Semont maneuver. In about 10 percent of cases, surgical treatment may be suggested if these therapies do not provide satisfactory outcomes. If you have experienced inexplicable vertigo or dizziness that lasts for over a week, see your balance disorder specialist.