Benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is a disorder characterized by short severe vertigo attacks when the head is moved in certain directions.

BPPV is a disorder of the inner ear that mainly affects older people and women over 40 years of age.

To understand this disease, it is necessary to analyze the terms:

• Positional vertigo is a feeling of the moving body or environment, although both do not move. The affected person feels malaise and nausea.
• Paroxysmal means that the symptoms are very intense, recurrent and sudden.
• Position-related means that the symptoms are triggered by certain head movements.
• Benign means that this disorder is not caused by a serious cause and occurs temporarily.

Development of benign paroxysmal positional vertigo (pathological anatomy)

The inner ear contains a bony labyrinth and inside a membranous labyrinth.
In the membranous labyrinth there are 3 arcades:

• The front or upper,
• The rear,
• The horizontal or lateral.

These ducts contain sensory cells (cilia) and an endolymph that makes it possible to detect the rotation of the head.
The labyrinth also contains two otolithic organs:

• Utriculus,
• Sacculus.

These structures detect linear acceleration, i.e. anterior-posterior movements, and also perceive gravity.

Otoliths (or earstones) are crystals of calcium carbonate found on the surface of the sensory cells of the utriculus in a gelatin dome.

Paroxysmal positional vertigo occurs when the otoliths coming from the utriculus move inside one of the semicircular canals.

Normally, there are only endolymphs in the arcades.

When otoliths enter an archway, they massively irritate the sensory hairs that are located in the ampoule (a structure in the semicircular canal from which the stimuli to the vestibular nerve emanate) of the semicircular canal in question and thus trigger dizziness.

Depending on the position of the otoliths, benign paroxysmal vertigo can be defined as:

• Cupulolithiasis – if they are attached to the ampoule,
• Canalolithiasis – if they are located inside an archway.

In addition, a nystagmus develops, a rhythmic and unwanted eye movement.
The direction of nystagmus depends:

• From the excitation of the ampoule nerve in the affected semicircular canal
• From the direct connection to the extraocular muscles.

The type of nystagmus depends on the semicircular canal affected by canalolithiasis.

The reason for the migration of otoliths is not clear.
The calcium crystals can break down due to trauma or viral infections, but in many cases they shift without any noticeable illness or trauma.
The cause could be a degeneration of the protein or gelatin matrix of the otolith membrane due to the aging process. (Fife D, FitzGerald JE. Do patients with benign paroxysmal positional vertigo receive prompt treatment? Analysis of waiting times and human and financial costs associated with current practice. Int J Audiol. 2005)

Benign paroxysmal positional vertigo may affect the following semicircular canal:

• Rear
• Horizontal
• anterior (rare),
• at least two arcades at the same time (very rare).

Due to its position, the posterior semicircular canal is most often affected.
The front one is less affected. (Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston LJ, Cass S, et al. Clinical practice guideline: Benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg. 2008).

Causes of benign paroxysmal positional vertigo

The cause of BPPV is usually unknown (idiopathic).
Since it is more common in middle-aged women, scientists believe that hormonal changes may affect the development of the condition.

In a scientific study, the calcium density in the bones is reduced in women and also in men with benign paroxysmal positional vertigo in contrast to people who do not suffer from dizziness (Jeong SH, Choi SH, Kim JY, Koo JW, Kim HJ, Kim JS. Osteopenia and osteoporosis in idiopathic benign positional vertigo. Neurology. 2009;72:1069–1076).
These results show a link between calcium metabolism and idiopathic BPPV.

Symptoms of benign paroxysmal positional vertigo

The main symptom is dizziness (feeling of spinning) caused by a movement of the head.
As a rule, a patient develops dizziness:

• When he rises from bed,
• When turning in bed,
• When tilting the head backwards, for example when looking upwards,
• When he leans forward, for example to tie the shoes.

Usually, a typical description of the symptom is:

“When I get up from bed, I suddenly feel dizzy, I think I’m falling, but if I wait a little, it passes again.”

Some add:
“I was frightened and immediately lay back on the bed, but the dizziness only got worse. Then I waited a bit and the symptom passed.”

“Every time I turn in bed, it spins in my head.”

However, symptoms may vary in patients and may show:

• Non-specific turning in the head,
• postural instability,
• Nausea (Giacomini PG, Alessandrini M, Magrini A. Long-term postural abnormalities in benign paroxysmal positional vertigo. ORL J Otorhinolaryngol Relat Spec. 2002;64:237–241).

The dizziness occurs intermittently and depends on its seat.
Patients with BPPV do not suffer from severe dizziness during the day when standing normally, but in the morning after getting out of bed.

Benign paroxysmal positional vertigo in the elderly

The juvenile form is characterized by a significant symptomatology, but in the elderly it occurs in a mild form.
The patient is ataxic (coordination problems) and feels symptom-free only when lying down.
In the elderly, this pathology is manifested by uncertainty, discomfort during washing, etc.

Diagnosis of benign paroxysmal positional vertigo

The responsible doctor is the ear, nose and throat specialist.

To establish a diagnosis, the doctor examines the type of nystagmus of the patient, which depends on the semicircular canal in which otoliths are located.

There are special changes to the head position for each channel.
The doctor moves the patient’s head in one direction and observes the eye movements.
If there is no reaction, he makes further movements to examine all the semicircular canals.

Posterior portico BPPV

For this type of storage vertigo, the Dix Hallpike storage sample is indicated.
The behaviour of otoliths in the posterior canal (canalolithiasis) in this test:

1. They move away from the dome,
2. They stimulate the posterior channel and influence the flow of the endolymph directed away from the ampoule (first Ewald law)

The excitation of the posterior channel activates:

1. The upper oblique eye muscles of the same side,
2. The lower outer eye muscles of the opposite side.

The result is a deviation of the eyes downwards and an upward rotation of the eyes.
In this case, the nystagmus is linear-rotatory.

Usually, the following applies to nystagmus:

• It starts with a few seconds delay,
• It passes again within a minute (usually within 30 seconds),
• Its direction is reversed in a sitting position.

Cupula-type paroxysmal positional vertigo causes a delay in the shorter nystagmus, but persists longer.
Repetition of the test several times causes a reduction:

1. of symptoms,
2. Of nystagmus.

Dix Hallpike storage sample for the diagnosis of posterior semicircular BPPV

This maneuver is the most important examination for diagnosing posterior semicircular BPPV.

However, there are contraindications, because the patient must perform a rotational movement and overextension of the neck, which can stretch and narrow nerves and arteries at the cervical level:

• In patients with previous neck surgery,
• In case of irritation of a cervical nerve root (for example, by compression),
• Dissection (detachment of a layer of the outer wall) of a vertebral or carotid artery
• For cervical circulatory disorders (for example, coronary artery narrowing)

Position of the patient:

Sitting upright, legs stretched out on the examination table.
The head is rotated 45° in the direction of the affected ear (the rotation to this side produces dizziness).

Test

The patient is taken to the back (abdomen upwards) and is carried out with the head:

• A rotation of about 45°,
• An extension of about 30 °, he must lie with his head over the edge of the couch and support himself only with the neck on the bed.

Hold this position for about a minute or until dizziness and nystagmus have passed.
Nystagmus begins when the patient lies down, after a few seconds the climax is reached.
It passes slowly and gradually, disappearing after about 20-40 seconds.

The test is positive if nystagmus and dizziness occur.

If the patient cannot perform this test, there is a variant in which he lies on his side.
The starting position is the same.
The patient quickly lies down on his side, turning his head 45° in the opposite direction.

Paroxysmal positional vertigo of the lateral semicircular canal

To diagnose benign paroxysmal positional vertigo of the lateral semicircular canal (horizontal), the Pagnini-McClure maneuver or roll test is performed.

Starting position:

Patient in supine position with head facing forward

Test

Rotation of the head by 90° to one side, rotation of the head by 90° to the opposite side.

During this maneuver, the horizontal nystagmus may turn out:

• To the ground (geotropical nystagmus) due to the migration of otoliths to the ampoule,
• Skyward (apogeotropic nystagmus) due to the migration of otoliths away from the ampoule.

With canalolithiasis in the lateral semicircular canal, the delay in the appearance of a nystagmus and its duration are longer than in the posterior semicircular canal.
The identification of the affected side is very important for setting up an effective vertigo treatment.
Ewald’s second law states that: the rotation to the healthy side causes nystagmus faster than the rotation to the affected side.

Determining the affected ear can be difficult due to a near-symmetrical response.
In these cases, other examinations may provide clues to determine the affected ear.
In the case of BPPV of the lateral channel, nystagmus can be caused by:

1. change of position from sitting to the supine position,
2. Head tilt forward when sitting.

In up to 80% of cases with horizontal BPPV, the nystagmus is opposite to the lying position when sitting.
In general, the nystagmus that occurs when lying down points to the affected side, while the nystagmus turns out to the opposite side when sitting.
In addition, the horizontal apogeotropic nystagmus can disappear if the head is rotated 10-20° to the affected side (zero point).

Spontaneous nystagmus (which occurs without cause) is not uncommon, it occurs in 70° of cases of BPPV of the lateral semicircular canal.
The cause may be the position of the lateral archway, which is inclined 30° to the horizontal plane.
Thus, gravity can push the otoliths in the arcades or cupula even in a sitting position.
For this reason, spontaneous nystagmus disappears when the head is tilted forward by 30°.
In this position, the effect of attraction is canceled out because the horizontal archway is aligned parallel to the horizontal plane.

Paroxysmal positional vertigo of the anterior semicircular canal

Benign paroxysmal positional vertigo of the anterior semicircular canal are rare.
The characteristics differ from those of the BPPV of the posterior portico.

In anterior semicircular BPPV, the straight head and the Dix-Hallpike maneuver on both sides can cause nystagmus that turns downwards, with a rotating component to the side of the affected ear (Brantberg K, Bergenius J. Treatment of anterior benign paroxysmal positional vertigo by canal plugging: a case report. Acta Otolaryngol. 2002;122:28–30).
Also, the rotational nystagmus is not as pronounced as in benign paroxysmal positional vertigo of the posterior semicircular canal.

• Paroxysmal positional vertigo: maneuvers, exercises and daue
• Dizziness or vertigo
• Dizziness: diagnosis, medications and natural remedies