Also referred to simply as “positional vertigo,” benign paroxysmal positional vertigo (BPPV) is a common form of balance disturbance that originates in the inner ear. Imagine waking up in the morning: you open your eyes and start to roll out of bed just as usual, but then you’re stopped by a sudden sensation that the room is spinning. You have to hold the furniture and walls just to get out of bed and take a few steps. After you stand in one position for a few minutes, the feeling passes.
This is the most common description given by patients with BPPV. It is a brief, intense sensation of spinning that occurs when getting out of bed or turning your head too quickly. Although frightening, it is most often harmless.
A functioning vestibular system
The inner ear houses the hearing organ (cochlea) and the balance organ, also called the vestibular system. The vestibular system is composed of the utricle, the saccule and three semicircular canals. The different structures of the vestibular system are all built in a similar manner. Very simply described, each structure is like a wired mini marshmallow in a Jello mold: they consist of nerve receptors that are embedded in a gelatinous mixture in which little calcium carbonate crystals float.
When the head changes direction, the change in gravity or velocity moves the crystals around in the gel and changes the pressure against the nerve receptors (imagine that Jello wobbling as you transfer it from the kitchen to the table). Each of the five vestibular system structures is oriented in a particular manner so that we can detect head position and motion in all different directions. When everything is working properly, the vestibular system helps us keep our balance whether we’re out walking, dancing the tango or doing a somersault.
The abnormally functioning vestibular system
Occasionally, the calcium carbonate crystals get disengaged from the gelatinous mixture and fall into the wrong space. The displaced crystals then cause abnormal stimulation of the nerve receptors when the head is moved in certain ways. This abnormal stimulation results in the perception of vertigo, or spinning. The reason why these crystals become disengaged and cause this condition is unknown about half of the time.
When there is a known cause for BPPV, it is commonly head injury or migraine. Traumatic head injury can mechanically jostle the crystals out of place; migraines can cause spasm of the labyrinthine artery, which can predispose patients to recurrent episodes of BPPV. Another related factor seems to be aging, as the condition is more common in the elderly than in younger populations.
Evaluation for BPPV
When you get an evaluation for dizziness, there are many tests that may be ordered by your physician. Several tests involve a trained healthcare provider observing the eyes (directly or via video recording) during and after a patient is carefully guided into a position that is likely to elicit vertigo, usually laying down on their back. If BPPV is present, the eyes will move in a particular way, known as nystagmus, indicating that there is abnormal nerve stimulation in the vestibular system. These patients will often report a spinning sensation as well.
Patients who have BPPV will have indicative eye movements, called nystagmus, that correspond with the abnormal nerve stimulation in the vestibular system.
After a few minutes, the eye movements will subside and the patient will be brought back up to a sitting position. The examiner will continue to guide the patient and observe any eye movements. In classic cases of this condition, returning the patient to the sitting position will elicit the nystagmus again, but to a lesser extent and in the opposite direction.
For a lot of people, BPPV is an unpleasant experience that occurs for a few days, in response to certain head positions and then fixes itself. The crystals will either move out of the way or dissolve and the problem is gone just as quickly as it arrived.
If you are evaluated by an ENT physician or an audiologist, there is a treatment that can be done in the office and at home to resolve the issue. The BPPV treatment consists of a guided series of postures that are designed to redirect any loose calcium carbonate crystals. The physician or clinician will physically guide you through the treatment because if it is successful, you will likely experience dizziness. As you are placed in the different postures, you will stay in each position until any dizziness fatigues. When all of the postures are completed, the crystals are typically cleared from the path of the nerve receptors.
As this condition has a high recurrence rate, the physician or clinician may send you home with a copy of the exercises for you to try on your own if you experience the symptoms again. As it is a mechanical issue within the vestibular system, there is no medication to treat or reduce the symptoms. This type of dizziness is rarely progressive and usually responds well to treatment, however, permanent issues may require surgical intervention.
What do I do if I feel dizzy?
Dizziness is a symptom of many different conditions. BPPV is just one condition that causes a spinning type of dizziness. If you are experiencing dizziness in any form—unsteadiness, lightheadedness or spinning—please contact your physician right away to determine the best course of action.