Dizziness – Benign Paroxysmal Positional Vertigo (BPPV)
Benign paroxysmal positional vertigo (BPPV) is a common vestibular (inner ear balance) disorder which is characterized by a false sense of spinning or rotational movement which results in the feeling of dizziness. Benign paroxysmal positional vertigo typically occurs suddenly with no apparent cause, and each episode usually lasts only for a brief time when the head is held in certain positions. While BPPV is not considered to be a serious condition, the dizziness associated with it can be temporarily debilitating and cause unsteadiness and loss of balance.
Other symptoms of benign paroxysmal positional vertigo include:
- Difficulty concentrating
- Unusual eye movements
Benign paroxysmal positional vertigo can affect people of any age, but is extremely rare in children and most common in patients over 50. When BPPV does present in younger patients, it is often a result of a head injury.
How Benign Paroxysmal Positional Vertigo Occurs
Benign paroxysmal positional vertigo is a mechanical problem in the inner ear which occurs when calcium carbonate crystals called otoconia become dislodged from the gel they normally rest in within the ear structure. These loose crystals can travel into one of the 3 canals of the vestibular labyrinth, the tiny organ in the ear which contains fluid and sensors that monitor head rotation.
Crystals that accumulate in one of the canals can interfere with fluid movement causing false signals of head motion to be sent to the brain. This misinformation relayed to the brain, which does not match the information from the other ear or the eyes, coupled with the fluid movement caused by the crystals creates the sensation of movement when there is none.
Types of benign paroxysmal positional vertigo are:
- Canalithiasis: This is the most common BPPV in which the loose crystals in the ear canal are able to move freely thus causing the vertigo. When the head is rotated, the spinning sensation usually lasts approximately one minute and, once the crystals have settled, the symptoms subside.
- Cupulolithiasis: In this less common form of BPPV, the loose crystals become caught on the sensory nerves within the ear canal which prolongs the episode and its symptoms until the head is moved into a position that dislodges the crystals from the bundle of nerves.
While the symptoms are similar, it is important to identify what type of benign paroxysmal positional vertigo is causing the symptoms, as each variant of BPPV is treated differently. Oftentimes, BPPV comes on suddenly when a patient is older because, as we age, the inner ear is affected by natural wear and tear that has occurred over time.
Benign paroxysmal positional vertigo often presents when the head changes positions such as:
- Standing up
- Rolling over in bed
- Tipping the head back
- Bending over
- Any quick head movement
Other possible factors that may trigger BPPV include:
- Disorders of the inner ear (such as Meniere’s disease)
- Certain types of migraines
- Keeping the head in one position for an extended length of time
- Lying in bed for long periods, such as while on bed rest or in hospital
- High intensity physical activity
- Being exposed to extremely bumpy terrain, such as during mountain biking
Diagnosing Benign Paroxysmal Positional Vertigo
Because the crystals involved in causing benign paroxysmal positional vertigo do not appear in imaging tests, such as an MRI, achieving a diagnosis involves identifying specific symptoms particular to BPPV. The most telling sign that a patient has BPPV is the exhibiting of certain eye movements called nystagmus. These involuntary eye movements, which are triggered by the crystals traveling in the ear canal, are actually what creates the false spinning sensation.
The characteristics of the specific nystagmus will determine which ear is affected by BPPV, as well as which canal the crystals have moved into. Recognizing these signs often requires a medical professional who is trained in vestibular disorders, as treatment is dependent on crystal location. The patient may also be asked to lie supine and tilt the head in particular ways to determine which rotations trigger vertigo.
Testing for BPPV may include:
- Dix-Hallpike Test: In this maneuver, the patient’s head is turned to either side 45 degrees, and then he/she lies back until the head hangs over the edge of the examination table. The doctor can then determine what position triggers BPPV symptoms.
- Supine Roll Test: While the patient lies on his/her back, the neck is flexed 20 degrees then rolled 90 degrees on each side to identify positions that trigger BPPV symptoms.
Both diagnostic tests may be utilized to determine accurate location of the crystal movement which will dictate the type of treatment necessary.
Learn about the treatment for Benign paroxysmal positional vertigo (BPPV).