Definition and Overview
Benign paroxysmal positional vertigo (BPPV) is a disease in which calcium carbonate crystals, or otoliths, in the vestibular organ inside the ear dislodge into the semicircular canal, causing repeated rotational dizziness lasting from a few seconds to a minute when a specific change in posture occurs. It is the most common cause of peripheral dizziness, accounting for approximately 20-30% of all dizziness patients.
According to population-based epidemiological studies, the lifetime prevalence is approximately 2.4%, the annual prevalence is approximately 0.6%, and it occurs two to three times more often in women than in men. It occurs more frequently after the age of 40, and the incidence increases with age.
The name 'benign' means that it is not a life-threatening central disease, 'paroxysmal' means that it occurs suddenly, and 'positional' means that it is caused by a change in posture.
Causes and Mechanisms
Mechanism of otolith expulsion
The utricle of the vestibular organ contains otoliths, which are calcium carbonate crystals, embedded in a gelatinous membrane. If the otolith separates from the oval sac and moves into the semicircular canal due to trauma, aging, viral infection, osteoporosis, or vitamin D deficiency, abnormal endolymph fluid flow occurs every time the head moves.
This abnormal fluid flow stimulates the cupula of the semicircular canal, and a rotational stimulation signal is transmitted to the brain even though there is no actual movement, causing dizziness and nystagmus.
associated risk factors
- Aging: The most powerful risk factor. Otolith adhesion decreases due to degeneration of the oval capsule membrane.
- Head trauma: Post-traumatic BPPV accounts for approximately 7-17% of all BPPV.
- After vestibular neuritis: BPPV occurs secondary to vestibular neuritis in approximately 10% of patients.
- Vitamin D deficiency: It has been reported that lower serum 25-OH vitamin D levels are associated with a higher rate of BPPV recurrence.
- Osteoporosis: Associated with abnormalities in the mineral content of otoliths.
- Prolonged bed rest: May cause weakening of the gelatinous membrane that supports the otolith.
Involving semicircular canal
- Posterior semicircular canal: This is the most common type, accounting for approximately 85-95% of all BPPV.
- Horizontal semicircular canal: The second most common, accounting for approximately 5-10%, and causes dizziness when lying down or turning the head to the left or right.
- Anterior semicircular canal: This is the rarest type.
symptoms
The core symptom of BPPV is rotational dizziness that suddenly appears when changing certain postures.
Characteristic symptom pattern
- Triggering positions: Dizziness occurs when lying down or getting up from bed, tilting or bending your head back, or turning your head in a certain direction.
- Duration: Mostly less than 1 minute, posterior semicircular canal BPPV lasts from a few seconds to 30 seconds. If it persists for more than 1 minute, other diseases should be diagnosed.
- Incubation period: Dizziness begins after a 2 to 5 second incubation period after a change in posture.
- Fatigue phenomenon: If you repeat the same posture, fatigue phenomenon occurs in which the intensity of dizziness gradually decreases.
- Accompanying symptoms: Nausea and vomiting may occur. There is no hearing loss or tinnitus.
Situations requiring differentiation
Central causes should be ruled out if the following applies:
- Dizziness lasts for several hours or more.
- Dizziness appears regardless of posture.
- It is accompanied by unilateral hearing loss, hemiparesis, and speech impairment.
- Balance is lost to the point where walking is impossible.
diagnosis
Diagnosis of BPPV is made through a characteristic history and provocative examination, and in most cases, clinical diagnosis is possible without additional imaging tests.
Dix-Hallpike Inspection
It is the standard diagnostic test for posterior semicircular canal BPPV.
1. Have the patient sit on the examination table. 2. Turn your head 45 degrees toward the direction to be diagnosed. 3. Support the patient's head and quickly lay it down so that the head is lowered 20 to 30 degrees below the examination table. 4. It is positive if rotary nystagmus and dizziness appear after a latency period of 2 to 5 seconds. 5. Nystagmus disappears within a few seconds to 1 minute, and when the patient is seated, nystagmus appears in the opposite direction.
The direction of nystagmus is characterized by ascending torsional nystagmus rotating toward the lower ear.
Supine Roll Test
It is used to diagnose horizontal semicircular canal BPPV. It is positive if horizontal nystagmus appears when the patient is lying down and the head is rotated 90 degrees alternately to both sides.
Video nystagmus test
Nystagmus is recorded with video glasses to quantitatively analyze the direction and intensity of nystagmus.
treatment
canalith repositioning maneuver
The canalith repositioning procedure is a non-invasive treatment that returns a displaced otolith to its original position.
Epley maneuver (posterior semicircular canal BPPV)
Developed by Epley in 1992. Move the head in steps 4 to 5 to move the otolith from the posterior semicircular canal to the oval capsule. According to evidence-based clinical guidelines, symptoms improve in approximately 80% of patients after one treatment, and the success rate is reported to be over 90% when repeated trials are performed.
Barbecue Roll technique (horizontal semicircular canal BPPV)
With the patient lying down, the head is sequentially rotated 270 degrees to the sound side.
medication
Because canalith repositioning is the main treatment, the role of drug treatment is limited. In the acute stage of severe nausea and vomiting, anti-vertigo or anti-emetic drugs can be used for a short period of time. Long-term drug treatment is not recommended as it may interfere with vestibular compensation.
vestibular rehabilitation exercise
Brandt-Daroff exercises are exercises that patients can perform on their own at home. Repeated postural changes disperse otoliths or promote central compensation. It is used when canalith repositioning maneuver is difficult or for the purpose of preventing recurrence.
Vitamin D supplementation
Studies have shown that vitamin D supplementation can reduce the recurrence rate in recurrent BPPV patients with serum vitamin D deficiency.
Progress and prognosis
The prognosis of BPPV is overall good. Approximately 80-90% of patients experience rapid improvement in symptoms after canalith repositioning maneuver, and natural recovery is possible without canalith repositioning maneuver, but it takes an average of 2-4 weeks.
The one-year recurrence rate is approximately 15-20%, and most cases of recurrence improve with the same treatment as before. If recurrence is frequent, causes such as vitamin D deficiency, osteoporosis, and vestibular migraine should be evaluated.
BPPV itself does not affect life, but early treatment is important in elderly patients due to the high risk of falls and fractures due to dizziness.
life guide
- For 48 hours immediately after canalith repositioning maneuver, avoid lying down as much as possible and maintain a sitting position.
- Sleeping with your head slightly elevated using a high pillow (10 to 15 cm) helps prevent early recurrence.
- Resume activities that move your head rapidly, such as swimming, yoga, or gymnastics, after symptoms have completely improved.
- Avoid driving, working at heights, or operating machinery when you feel dizzy.
- If symptoms recur, a quick way to resolve the symptoms is to visit a specialist without delay and receive canalith repositioning maneuver.
- If you have osteoporosis or vitamin D deficiency, concurrent treatment is beneficial in preventing recurrence.