Vertigo otolith

I. Definition

Benign paroxysmal positional vertigo (BPPV), commonly known as otolith, is the most common peripheral vestibular disease. It is a peripheral vestibular disease induced by the change of head position relative to the direction of gravity, which is characterized by recurrent transient vertigo and characteristic nystagmus. It is often self-limited and easy to relapse.

Second, the pathogenesis

The exact pathogenesis is still unclear. At present, there are two accepted theories.

1. Small tubule calculus: Otolith particles on oval cystic spots fall off and enter the lumen of semicircular canal. When the head position changes relative to the direction of gravity, otolith particles move relative to the semicircular canal wall under the action of gravity, which causes endolymphatic flow and leads to the deviation of ampulla crest, thus showing corresponding signs and symptoms. When otolith particles move to the new lowest gravity point in the semicircular canal cavity, the flow of endolymphatic stops, the crest returns to its original position, and the symptoms and signs disappear.

2. Crest gallstone disease: Otolith particles on the oval cystic spot fall off and attach to the crest of ampulla, which leads to the change of the density of crest phase relative to endolymphatic, making it sensitive to gravity, thus causing corresponding symptoms and signs.

Third, classification

1. According to the etiology:

The etiology is unknown and usually falls into two categories.

(1) Idiopathic BPPV: The etiology is unknown, accounting for about 50% ~ 97%.

(2) Secondary BPPV: secondary to other otology or systemic diseases, such as Meniere's disease, vestibular neuritis, idiopathic sudden deafness, otitis media, head trauma, migraine, postoperative (middle ear and inner ear surgery, oral and maxillofacial surgery, orthopedic surgery, etc.). ) and ototoxic drugs.

1. According to the classification of involved semicircular canals:

(1) BPPV of posterior semicircular canal: the most common, accounting for about 70% ~ 90%, of which crest stones account for about 6.3%.

(2) External semicircular canal BPPV (horizontal semicircular canal BPPV): about 10% ~ 30%. According to the types of nystagmus in rolling test, it can be further divided into geostrophic nystagmus and off-ground nystagmus, of which geostrophic nystagmus accounts for the vast majority.

(3) BPPV of anterior semicircular canal: rare type, accounting for about 1% ~ 2%.

(4) Multiple semicircular canals BPPV: Multiple semicircular canals or two semicircular canals on the same side were involved at the same time, accounting for 9.3% ~ 12%.

Fourth, clinical manifestations.

A typical BPPV attack is a sudden transient vertigo (usually lasting less than 1 min) induced by the patient changing his head position relative to the direction of gravity (such as getting up, lying down, turning over in bed, lowering his head or raising his head). Other symptoms may include autonomic nervous symptoms, such as nausea and vomiting, dizziness, top-heavy, floating, imbalance and vibration hallucinations.

Verb (abbreviation of verb) diagnosis

1. Recurrent and transient vertigo or dizziness (usually lasting less than 65438 0 minutes) occurs after changing the position of the head relative to the direction of gravity.

2. Vertigo and characteristic postural nystagmus appeared in postural test.

3. Exclude other diseases, such as vestibular migraine, vestibular attack, central positional vertigo, Meniere's disease, vestibular neuritis, labyrinthitis, upper semicircular canal fissure syndrome, posterior circulation ischemia, postural hypotension, psychogenic vertigo, etc.

Six, check

Basic inspection: position test.

Select the examination according to the condition:

1. Vestibular function examination: including spontaneous nystagmus, gaze nystagmus, nystagmus, stable tracking, saccade, cold and heat test, rotation test, head shaking test, head pulse test, vestibular rotation test, vestibular evoked myogenic potential, subjective vertical vision/subjective horizontal vision, etc.

2. Audiology examination: pure tone audiometry, acoustic immittance, auditory brainstem response, otoacoustic reflex, cochlear electrogram, etc.

3. Imaging examination: high-resolution CT of temporal bone and internal auditory canal-cerebellopontine angle brain MRI.

4. Balance function check: static or dynamic posturography, balance sensory integration ability test, gait evaluation.

5. Etiological examination: including calcium ion, blood sugar, blood lipid, uric acid, sex hormone and other related examinations.

Seven, treatment

1. Otolith reset.

At present, the main methods to treat BPPV are simple and easy to operate, and can be done by hand or with the help of instruments, with good results. The corresponding methods should be selected according to the different types of semicircular canals during reduction. Include manual reduction and otolith reduction assisted by instrument.

2. medication.

Drugs can't reset otoliths in principle, but in view of the fact that BPPV may be related to degenerative diseases of the inner ear or complicated with other vertigo diseases, drug-assisted treatment can be considered in the following situations.

(1) When it is combined with other diseases, such diseases should be treated at the same time.

(2) When symptoms such as dizziness and imbalance appear after reset, drugs to improve inner ear microcirculation can be given, such as betahistine and Ginkgo biloba extract.

(3) Because vestibular inhibitors can inhibit or slow vestibular compensation, routine use is not recommended.

3. Surgical treatment.

For the refractory patients with clear diagnosis and clear responsibility of semicircular canal, if comprehensive treatment such as otolith reduction is still ineffective 1 year or more, and the activity is severely limited, surgical treatment such as semicircular canal obstruction can be considered.

4. Vestibular rehabilitation training.

Vestibular rehabilitation training is a physical training method, which can improve patients' vestibular function and reduce the sequelae caused by vestibular injury through central adaptation and compensation mechanism. Vestibular rehabilitation training can be used as an auxiliary treatment for otolith reduction of BPPV patients, which can be used for cases where the reduction is ineffective and dizziness or balance disorder still exists after reduction, and can also be used to increase the patient's tolerance to reduction before reduction treatment. If the patient refuses or cannot tolerate reduction therapy, vestibular rehabilitation training can be used as an alternative therapy.

I have introduced three kinds of diseases caused by dizziness. In order to make it easier for everyone to compare and read, I have sorted them out:

Halovestibular neuritis

Vertigo-vestibular migraine

Dizziness-Meniere disease

refer to

2 Practical Otolaryngology Head and Neck Surgery 2nd Edition [J]. China Medical Abstracts (Otolaryngology), 2008(2):237-237.