Causes, Incidence, and Risk Factors

Within the labyrinth of the inner ear lie collections of calcium crystals known as otoconia or otoliths. In patients with BPPV, the otoconia are dislodged from their usual position within the utricle, and migrate over time into one of the semicircular canals (the posterior canal is most commonly affected due to its anatomical position). When the head is reoriented relative to gravity, the gravity-dependent movement of the heavier otoconial debris (colloquially "ear rocks") within the affected semicircular canal causes abnormal (pathological) endolymph fluid displacement and a resultant sensation of vertigo. This more common condition is known as canalithiasis.

In rare cases, the crystals themselves can adhere to a semicircular canal cupula, rendering it heavier than the surrounding endolymph. Upon reorientation of the head relative to gravity, the cupula is weighted down by the dense particles, thereby inducing an immediate and sustained excitation of semicircular canal afferent nerves. This condition is termed cupulolithiasis.

There is evidence in the dental literature that malleting of an osteotome during closed sinus floor elevation, otherwise known as osteotome sinus elevation or lift, transmits percussive and vibratory forces capable of detaching otoliths from their normal location and thereby leading to the symptoms of BPPV.

It can be triggered by any action which stimulates the posterior semi-circular canal, including:

• Looking up or down
• Preceding head injury 
• Sudden head movement
• Rolling over in bed
• Tilting the head

BPPV may be made worse by any number of modifiers which may vary between individuals:

• Changes in barometric pressure— patients may feel increased symptoms up to two days before rain or snow
• Lack of sleep (required amounts of sleep may vary widely)
• Stress

An episode of BPPV may be triggered by dehydration, such as that caused by diarrhea. For this reason, it commonly occurs in post-operative patients who have diarrhea induced by post-operative antibiotics.

BPPV is one of the most common vestibular disorders in patients presenting with dizziness; migraine is implicated in idiopathic cases. Proposed mechanisms linking the two are genetic factors and vascular damage to the labyrinth.

Although BPPV can occur at any age, it is most often seen in people over the age of 60. Besides aging, there are no major risk factors known for developing BPPV, although previous episodes of trauma to the head, or inner ear infections known as labyrinthitis, may predispose individuals to future development of BPPV.

Benign Positional Vertigo is due to a disturbance within the inner ear. The inner ear has fluid-filled tubes called semicircular canals. The canals are very sensitive to movement of the fluid, which occurs as you change position. The fluid movement allows your brain to interpret your body's position and maintain your balance.

Benign Positional Vertigo develops when a small piece of bone-like calcium breaks free and floats within the tube of the inner ear. This sends the brain confusing messages about your body's position.

The inside of the ear is composed of an organ called the vestibular labyrinth. The vestibular labyrinth includes semicircular canals, which contain fluids and fine hairlike sensors which act as a monitor to the rotations of the head. An important structure in the inner ear includes the otolith organs which contain crystals that are sensitive to gravity. These crystals are responsible for sensitivity to head positions, and can also be dislocated, causing them to lodge inside one of the semicircular canals, which causes dizziness.

There are no major risk factors. However, the condition may partly run in families. A prior head injury (even a slight bump to the head) or an inner ear infection called labyrinthitis may make some people more likely to develop the condition.

BPPV can result from a head injury or simply occur among those who are older. 

A specific cause is often not found.

The Causal Mechanism

The underlying mechanism involves a small calcified otolith moving around loose in the inner ear. It is a type of balance disorder along with labyrinthitis and Ménière's disease. 



Diagnosis is typically made when the Dix–Hallpike test results in nystagmus (a specific movement pattern of the eyes) and other possible causes have been ruled out. In typical cases medical imaging is not needed.

The Medical Perspective

Occasionally, medications may be prescribed to relieve the spinning sensations. Such drugs may include:

• Antihistamines
• Anticholinergics
• Sedative-hypnotics

However, these medicines often do not work very well for treating vertigo.

To prevent your symptoms from getting worse during episodes of vertigo, avoid the positions that trigger it.

Expectations (prognosis)

Benign positional vertigo is uncomfortable, but usually improves with time. This condition may occur again without warning.

Complications

Patients with severe vertigo may get dehydrated due to frequent vomiting.

Calling your health care provider

Call your health care provider if:

• You develop vertigo
• Treatment for vertigo has not worked
• You develop symptoms such as weakness, slurred speech, or vision problems that may be signs of a more serious condition

Medicines Two Choices for You

As with ALL medications, there will be side-effects and other unforeseen consequences.  Research these and discuss them with your doctor or pharmacist BEFORE heading down the road of no return. Consider Dr. Huntoon's Alternative Medical Treatment Options next.