Peripheral vascular destructive labyrinthine syndrome

Peripheral vascular destructive labyrinthine syndrome (AUL). This form of the disease of the ear maze was first described by P. Meienier in 1848 by a young woman who, traveling in a diligence in winter, suddenly died out on both ears, she also had dizziness and vomiting. These symptoms persisted for 4 days, and on the 5th day she died. At the autopsy in the ear maze was found hemorrhagic exudate. This clinical case remains mysterious to this day; one can only assume that the deceased suffered a severe form of a bilateral influenza labyrinthitis.

Many times have passed since then, and in clinical practice there are many cases of so-called acute labyrinthopathy, during which sudden hearing loss or deafness occurs in one ear, noise in it and pronounced signs of vestibular dysfunction (dizziness, spontaneous nystagmus, nausea, vomiting, etc. .), indicating the hypofunction or deactivation of the vestibular apparatus on the side of the affected ear.

[1],

Causes of the peripheral vascular destructive labyrinth syndrome

The causes of peripheral vascular destructive labyrinth syndrome are manifold; its causes may be diabetes, blood diseases, vertebral-basilar vascular insufficiency, atherosclerosis, hypertensive or hypotensive arterial syndrome, as well as viral lesions of the ear maze. In some cases, AOL occurs as a result of a strong baroacoustic injury or gas embolism of branches of the labyrinthine artery with caisson disease.

[2], [3], [4], [5], [6]

Pathogenesis

Pathogenesis is determined by two possible immediate causes of peripheral vascular destructive labyrinth syndrome - ischemic or hemorrhagic its forms.

Ischemic form. Of the three mechanisms of ischemia (angiospastic, obturation, compression) for the peripheral vascular destructive labyrinth syndrome, the first two are characteristic.

Angiopathic ischemia occurs as a result of irritation of the vasomotor centers, while factors such as catecholamines (mental stress), chemicals (adrenaline, vasopressin, opium, ergotin), trauma (pain shock), microbial toxins can act as irritants causing angiospasm , general and cerebral hypertension, etc. These factors can cause angiospasm of labyrinth arteries to varying degrees, however, such risk factors for the occurrence of vasospastic forms of peripheral vascular labyrinth destructive syndrome as vertebral-basilar vascular insufficiency, gipertei-invasive crises, psycho-emotional stress.

Obturation ischemia occurs when the lumen of the artery is clogged with a thrombus or embolus, or it can develop as a result of a thickening of the artery wall with narrowing of its lumen as a result of some pathological process (atherosclerosis, nodular periarteritis, inflammatory process). For the peripheral vascular destructive labyrinth syndrome the atherosclerotic process is most typical, and the most typical combination of pathogenetic factors is its combination with angiospasm, which develops in labyrinth arteries.

The pathogenesis of ischemia, which is so characteristic of many diseases of the ENT organs, is as follows: oxygen starvation of the tissue, accompanied by a characteristic metabolic disorder; in the tissues there is an accumulation of toxic nedookisleinnyh products of metabolism (catabolites); CBS is shifted towards acidosis; the phenomena of anaerobic decay of tissues are amplified; the accumulation of acid metabolic products leads to swelling of tissues, secondary compression ischemia and an increase in the permeability of vascular and cell membranes (secondary labyrinth hydrops), stimulation of receptor formations. The resulting metabolic disorders lead first to a disruption of the function of the organ, tissue (reversible stage), and then to structural changes in the form of dystrophic, atrophic, necrobiotic processes, up to complete necrosis (irreversible stage).

The consequences of ischemia depend both on the degree of infringement of blood flow, and on the sensitivity of tissues to oxygen starvation. In the ear maze, the hair cells of CpO are more sensitive to hypoxia, as phylogenetically younger than to the vestibular receptors, so they die earlier in ischemia of the inner ear. With a short duration of ischemia and appropriate treatment, recovery of not only vestibular but also auditory function may occur.

The hemorrhagic form of the peripheral vascular destructive labyrinth syndrome is characterized by hemorrhages in the cavity of the inner ear, which can be either limited (for example, only in the cochlea or in some semicircular canal), or generalized, that capture most of the ear maze. One of the main causes of this form of peripheral vascular destructive labyrinth syndrome is the hypertensive crisis that has arisen against the background of increased permeability of the vascular wall. As a primary cause of the peripheral vascular destructive labyrinth syndrome, various hemorrhagic diathesis (hemophilia, thrombocytopenia and thrombocytopathy, thrombohemorrhagic syndrome, hemorrhagic vasculitis, etc.), diabetes, hemorrhagic fevers can occur in some acute infectious diseases (influenza, shingles of the inner ear and other viral diseases ).

A hemorrhagic form of the peripheral vascular destructive labyrinth syndrome is characterized by a sudden increase in intra-labyrinth pressure and the emergence of hypoxia followed by complete degeneration of the inner ear receptors.

Two-sided AOL is extremely rare and, as a rule, ends with complete deafness and persistent impairment of vestibular apparatus function.

[7], [8], [9]

Symptoms of the peripheral vascular destructive labyrinth syndrome

Symptoms of the peripheral vascular destructive labyrinth syndrome are manifested by a sudden violent cochleovestibular crisis without any precursors, and the hemorrhagic form manifests itself most often during physical stress, severe emotional stress, and ischemic form - during sleep in the pre-weaning hours. Symptoms of the crisis are typical for an attack of Meniere's disease, and often they develop against a background of chronic hypertensive encephalopathy or are accompanied by signs of acute hypertensive encephalopathy. A distinctive feature of Meniere's disease with AOL is a persistent decrease in hearing that never returns to the baseline level, and a sharp deterioration in the perception of sound in both air and bone conduction with breaks in the curves of the tonal threshold audiogram at high frequencies. The arising spontaneous nystagmus can only be directed to the side of the affected ear for a short time (minutes, hours), even then with a slow increase in ischemia. In all other cases, it immediately acquires the features of turning off the labyrinth and is directed toward the uninfected ear.

AUL, along with cochlear and vestibular syndromes (severe ear noise, rapidly increasing hearing loss, down to total deafness, severe system dizziness, spontaneous nystagmus, falling toward the affected ear, nausea and vomiting) are usually accompanied by a headache and a series of vegetative symptoms related to the cardiovascular, respiratory and autonomic systems. In some cases, the patient develops a collapoid state and loss of consciousness. It is these signs that are most characteristic of the apoplexy of the vestibular part of the ear maze, but if hemodynamic and hemorrhagic disturbances occur only in the cochlear, then the vestibular symptoms can be poorly expressed or even not seen during sleep, and the patient, when awakened, suddenly notices severe hearing loss or even deafness in one ear.

Having arisen suddenly, the cochleovestibular crisis lasts several days, and then gradually its severity decreases, and the auditory function either remains at a low level, or is turned off, or is somewhat restored (after a short-term ischemic crisis), and the symptoms of the vestibular crisis pass, but the chronic vestibular insufficiency, lasting for many months. Patients who have undergone AUL remain invalid for a month or more and need a long rehabilitation period. They are counter-indicative of work at altitude, professional driving of vehicles, service in the Armed Forces as conscripts.

Forms

Peripheral tympanogenous labyrinthine syndrome. This syndrome can sometimes be observed in chronic or acute purulent diseases of the middle ear (induced labyrinthopathy). It occurs due to irritation of the tympanic plexus, the penetration of toxins through the windows of the labyrinth in the inner ear or through microcirculatory blood and lymphatic ways. Peripheral tympanogenous labyrinth syndrome manifests as attacks of light dizziness, noise in the ear, which quickly pass through the effective treatment of the inflammatory process in the CrN. This syndrome should be differentiated from the initial stage of serous labyrinthitis, which arose as a complication of acute or exacerbation of chronic purulent otitis media.

Another form of peripheral tympanogenous labyrinth syndrome is a process, interpreted as cicatricial labyrinthosis, which arises as a result of a limited labyrinthitis in the area of the labyrinth windows and penetration of scar tissue into peri- and endolymphatic space. This form of peripheral tympanogenous labyrinth syndrome is characterized by progressive hearing loss, ear noise hidden by vestibular dysfunction, which is detected only in the case of a bithermal caloric test in the form of mixed interlabyrinth asymmetry (both side and direction).

Acute catarrhal tubo-otitis can also provoke mild labyrinthine dysfunctions, caused by the retraction of the tympanic membrane and the corresponding impression of the base of the stapes on the threshold of the labyrinth. Symptoms of peripheral tympanogenous labyrinth syndrome (ear noise, mild dizziness, slight increase in vestibular apparatus excitability on the side of the patient's ear) disappear when restoring the patency of the auditory tube and eliminating catarrhal inflammation in it and in the middle ear.

Chronic catarrhal tubo-otitis, obliteration of the auditory tube is rarely manifested by vestibular symptoms; these diseases are characterized by progressive hearing loss starting from the conductive, continuing mixed and ending with the preceptive without any special hopes for successful non-operative treatment.

[10], [11], [12]

Diagnostics of the peripheral vascular destructive labyrinth syndrome

The diagnosis is based on a characteristic clinical picture - the sudden appearance of a "destructive" labyrinth syndrome: dizziness and spontaneous nystagmus toward the healthy ear, noise and sudden hearing loss (deafness) to the patient ear, equal hearing loss in both airborne and bone grafting, lack of anamnesis of similar attacks.

[13], [14], [15]

Differential diagnosis

Differential diagnosis is carried out with Meniere's disease, stem and supertherapeutic apoplexy syndromes. Differential diagnostics with acousto-vestibular neuritis, especially with syphilitic meningoneuritis of the pre-cochlear nerve and cerebral membranes of MMU, is more difficult.

[16], [17], [18]

Treatment of the peripheral vascular destructive labyrinth syndrome

Treatment depends on the shape of the peripheral vascular destructive labyrinth syndrome.

With vasospastic form appoint vasodilators (xanthinal nicotinate, nicotinoyl-GABA, cinnarizine), alpha-adrenoblockers (dihydroergotoxin), angioprotectors and microcirculation correctors (betagistin). At the same time, the appointment of cerebral circulation correctors (vinpocetine, nicotinic acid, pentoxifylline) is indicated. The drugs of choice are vasodilators such as bendazole, hydralazine, minoxidil, sodium nitroprusside.

With the obturation form of peripheral vascular destructive labyrinth syndrome, individual selection of the above mentioned agents in combination with hypolipidemic and antisclerotic drugs, as well as with antiaggregants (acetylsalicylic acid, dipyridamole, indobufen, clopidogrel) is performed.

When hemorrhagic form of peripheral vascular destructive labyrinth syndrome, angioprotectors and microcirculation correctors, antihypoxants and antioxidants (dimephosfon, vinpocetine) are used. However, the use of these drugs is directed not so much to restoring the function of the ear maze, which is lost irretrievably for hemorrhagic apoplexy, but for the prevention of more severe vascular disorders of the brain, and in particular in the vertebral-basilar basin. Patients with suspected AOL should be examined by a neurologist to exclude acute cerebrovascular insufficiency of the brain.

Forecast

The prognosis for auditory function is unfavorable, with respect to vestibular function - cautious, otherwise - is determined by the disease that caused the occurrence of peripheral vascular destructive labyrinth syndrome.

[19], [20], [21], [22]