Inflammation of the cranial nerves. Symptoms of damage to the cranial nerves

Trigeminal neuralgia - damage to the cranial nerves - the most common of all types of neuralgia.

Causes of cranial nerve damage

In the etiology of trigeminal neuralgia give great importance narrowing of the bony openings where the branches of the nerve pass. Often the cause of neuralgia is SARS, rheumatism, malaria, as well as various inflammatory diseases of the accessory cavities of the nose and teeth. With trigeminal neuralgia, the main clinical picture is a short-term attack (from several seconds to several minutes) of extremely intense pain. They are localized more often in the region of any one branch. There is irradiation of pain in all branches and even in the region of the neck, arms, neck, but the pain never passes to the opposite side. Attacks of pain may be accompanied by reflex contractions of the facial and chewing muscles in the form tonic convulsions corresponding half of the face. Along with this, it is noted autonomic disorders: hyperemia of half of the face, redness of the conjunctiva, lacrimation, increased salivation.

Neuritis (neuropathy) of the facial nerve - damage to the VII pair of cranial nerves (prosoplegia, Bell's palsy), occurs most often after hypothermia, after influenza and other infections.

matter congenital anomaly facial (fallopian) canal, periostitis, venous congestion. Often, Bell's palsy is secondary - with inflammatory processes of the middle ear and temporal bone, with injuries of the skull, especially with a fracture of the base, with processes in the membranes of the base of the brain inflammatory nature and tumors in the cerebellopontine angle. Paralysis of the facial nerve may be due to the pontine form of poliomyelitis or encephalitis caused by the Coxsackie virus.

Symptoms of cranial nerve damage

The clinical picture of the defeat of the cranial nerves is characterized by paralysis or paresis of all the facial muscles of the corresponding half of the face - the patient cannot collect wrinkles on the forehead, frown, close the eye, while the palpebral fissure gapes (lagophthalmos). At try-301

when you close your eye, you observe the rolling of the eyeball up and a wide strip of sclera - Bell's symptom. On the side of paralysis, the corner of the mouth is sharply lowered, the patient cannot "bar" his teeth, inflate his cheeks - the air is released freely. Liquid food pours out of the corner of the mouth. The asymmetry of the face is especially often seen when smiling and laughing. When the facial nerve is damaged above the discharge of the tympanic string (chorda tympani), facial paralysis is accompanied by a taste disorder in the anterior 2/3 of the corresponding half of the tongue. The lesion over the stapedial nerve (n. stapedius) is characterized by hyperkusia. Localization of the process above the departure of the large stony nerve gives a sharp violation of lacrimation and dryness of the eye. When the process is localized in the area of ​​the geniculate ganglion, Gunt's symptom may develop - a rash of herpetic vesicles on the anterior surface auricle, external auditory canal, tympanic cavity, in the back of the palate and on the front half of the tongue.

Peripheral paralysis of the facial nerve is combined with pain and decreased sensitivity in the relevant areas. Damage to the facial nerve in the area cerebellopontine angle accompanied by a violation of the VIII pair, cerebellar disorders on the side of the focus and pyramidal symptoms on the opposite side.

In the clinical picture of this lesion of the cranial nerves, trigeminal nerve and neuropathy of the facial nerve, pain, inflammatory, metabolic, dystrophic and neuropathic syndromes are distinguished.

The treatment of neuropathy (neuralgia) includes anti-inflammatory (antibiotics, glucocorticoids), immunosuppressive, diuretic, desensitizing drugs, vitamins B1, B6 and B12 that have a reparative-regenerative effect on the nerve, as well as metabolic and trophostimulating effects,

analgesics (analgin, ibuprofen, indomethacin, diclofenac), mediators (prozerin, nevaline, galantamine), substances that improve the conduction of impulses along the nerve fiber.

Physical methods of treatment are used to relieve pain (analgesic and anesthetic methods), relieve inflammation and edema (anti-exudative and decongestant, reparative-regenerative methods), improve microcirculation (vasodilating methods) and metabolism (hypo-coagulative methods), improve the function of neuromuscular -muscle fiber (neurostimulating methods).

The sense of smell can be impaired due to: 1) impaired access of the odorant to the olfactory neuroepithelium (transport loss of smell), for example, due to swelling of the nasal mucosa in acute respiratory diseases, allergic rhinitis, or due to structural changes in the nasal cavity (curvature of the nasal septum , polyps, tumor); 2) damage to the receptor zone (sensory loss of smell), for example, destruction of the olfactory epithelium during viral infections, tumor processes, inhalation of toxic chemicals, head irradiation; 3) damage to the olfactory pathways (neural loss of smell), for example, as a result of trauma with or without a fracture of the cribriform plate, neoplasms of the anterior cranial fossa, neurophysiological procedures, neurotoxic drugs, or congenital disorders such as Kallmrn's syndrome.

Optic nerve (II)

Visual disturbances can be explained by damage to a certain part of the visual pathway when examining the eyeball, retina or nipple optic nerve or with careful, to the smallest nuances, checking the fields of vision. Retinal lesions cause arcuate, central, or centrocecal scotomas. Lesions of the chiasm lead to bitemporal hemianopia. Homonymous hemianopia occurs in lesions located behind the chiasm, complete defeat localization does not make sense. Partial incongruent homonymous hemianopsia suggests damage to the optic tract or pathways (optic tract involvement is suspected when there is a combination of optic nerve atrophy and an afferent pupillary defect, whereas when the area beyond geniculate body pupils remain normal). Congruent (identical) homonymous hemianopsia means damage to the cortex.

intraocular fluid and glaucoma

Glaucoma- a condition in which increased intraocular pressure (more than 22 mmHg), transmitted through the intraocular fluid, damages the optic nerve. Glaucoma is the leading cause of blindness in the US.

Open angle glaucoma. Rarely causes eye pain or corneal swelling. Loss of vision is noted first at the periphery of the visual field, visual acuity is normal until the late stage of the disease. Treatment: topical cholinergic drugs (pilocarpine or carbachol) and beta-blockers (timolol) with or without carbonic anhydrase inhibitors (acetazolamide or methazolamide).

Angle-closure glaucoma. May be caused (accelerated) by taking drugs that dilate the pupils. Symptoms: loss of vision, dilated pupils, pain and (in the acute process) erythema. Is an emergency and requires treatment intravenous administration mannitol, parenteral acetazolamide, and topical pilocarpine or timolol.

congenital glaucoma. Rarely.

secondary glaucoma. May be associated with leukemia, sickle cell anemia, Waldenström macroglobulinemia, ankylosing spondylitis, rheumatoid arthritis, sarcoidosis, congenital rubella, onchocerciasis, amyloidosis, osteogenesis imperfecta, tumor metastases, neurofibromatosis, Sturge-Weber syndrome, constant reception glucocorticoids, amphetamines, hexamethonium, reserpine, anticholinergics, eye trauma, lens displacement (homocystinuria and Marfan's syndrome).

Retina

Retinal diseases include vasopathy, associated with the most common diseases (hypertension, diabetes mellitus); occlusion central artery retina(with segmental division of blood flow in the retinal veins, milky white retina and cherry red spot due to the preserved vascularization of the choroid itself), due to embolism, temporal arteritis, atherosclerosis, vasculitis, increased viscosity blood; transient monocular blindness(amaurosis fugax) due to attacks of retinal ischemia, usually associated with ipsilateral stenosis carotid artery or embolism of the retinal arteries. Usually, an attack of blindness develops quickly (from 10 to 15 seconds) and is described by the patient as a shadow, smoothly and painlessly darkening the field of vision, falling from top to bottom. In other cases, the visual defect can be described as a narrowing of the visual field from below. Blindness lasts for seconds or minutes, and then the vision clears slowly and evenly in reverse order. This condition can be distinguished from the transient blindness of classic migraine, as the latter often begins with shapeless flashes of light (photopsia) or zigzag lines (a dark zigzag spot or teichopsia) moving across the visual field for several minutes, leaving the hemia. nopsic scotoma (although patients may indicate monocular symptoms). Retinal diseases can also be caused by a degenerative process that occurs with retinitis pigmentosa, with concomitant multisystem diseases and toxic effects. medicines, including phenothiazines or chloroquine.

optic nerve

Retrobulbar optic neuropathy, or optic neuritis. It is characterized by rapid (hours or days) development of visual impairment in one or both eyes, usually due to acute demyelination of the optic nerve. The disease often occurs in children, adolescents or young adults. Complete blindness is rare. On examination: the optic disc and retina are normal or there may be inflammation of the optic nerve papilla; eye movements or pressure on the eyeballs cause pain; central vision is impaired to a greater extent than peripheral vision, the pupil's reflex to light is impaired (light flash test). CSF is normal or there is pleocytosis (10-20/mcL) with or without any cell dominance. In 50% of cases, signs of multiple sclerosis develop over the next 15 years. Other causes of the disease include postinfectious or disseminated encephalomyelitis, posterior uveitis, vascular lesions of the optic nerve, tumors (optic nerve glioma, neurofibromatosis, meningioma, metastases), and fungal infections.

Anterior ischemic optic neuropathy. Occurs as a result of atherosclerotic or inflammatory disease of the ophthalmic artery or its branches. It presents as an acute painless monocular visual loss with an upper field defect. The optic papilla is pale and edematous with pinpoint peripapillary hemorrhages, the macula and retina are normal. Examination should rule out temporal arteritis. Sometimes microembolism can be the cause of anterior ischemic optic neuropathy (for example, after heart surgery).

Toxic or trophic visual neuropathy. It manifests itself as a simultaneous visual impairment in both eyes with central or centrocecal scotomas, developing over days or weeks. Toxic substances: methanol, chloramphenicol, ethambutol, isoniazid, sulfonamides, streptomycin, digitalis, ergot, heavy metals.

Bitemporal hemianopsia due to the spread to the suprasellar zone of a pituitary tumor or saccular aneurysm of the circle of Willis, or meningioma of the tubercle of the Turkish saddle, or, less commonly, develops in connection with sarcoidosis, metastases and Hand-Christian-Schuller disease.

Oculomotor, trochlear and abducens nerves (III, IV, VI)

Isolated paralysis of the III or VI cranial nerves. May be caused by diseases such as diabetes mellitus, neoplasms, increased intracranial pressure (VI nerve), pontine glioma in children or metastatic nasopharyngeal tumor in adults (VI nerve), brain base tumor (III nerve), ischemic nerve infarction, aneurysm of Willis circle. With compression lesions of the third nerve, the pupil is usually dilated, while with nerve infarction, the pupils are not changed.

Lesions III, IV and VI nerves. They can occur at the level of their nuclei, along their length from the brain stem through the subarachnoid space, cavernous sinus, or superior orbital fissure (Table 173-1).

Table 173-1 Cranial Nerve Syndromes

Source: modified Victor M, Martin JB: NRSh-13, p.2351

Tolosa-Hunt syndrome. Painful combined unilateral lesions* due to parasellar granuloma.

pituitary apoplexy. Acute unilateral or bilateral ophthalmoplegia and visual field defect, accompanied by headache and (or) drowsiness.

Ophthalmoplegia in migraine. Transient ophthalmoplegia in typical migraine.

Trigeminal nerve (V)

Trigeminal neuralgia (tic douloureux). Frequently repeated, excruciating attack of pain in the lips, gums, cheeks or chin (rarely in the zone of innervation of the first branch of the trigeminal nerve), lasting from several seconds to several minutes. It occurs in middle-aged or elderly people. Pain is often provoked by irritation of trigger zones. Violation of sensitivity is not detected. It should be differentiated from other forms of facial pain resulting from diseases of the jaw, teeth or paranasal sinuses nose. Trigeminal neuralgia is rarely caused by herpes virus zoster or tumor. Treatment: carbamazepine (1-1.5 g/day in divided doses) is effective in 75% of cases; during treatment, a clinical blood test should be performed to identify rare complication treatment for aplastic anemia. If medical treatment fails, surgical destruction of the ganglion or suboccipital craniectomy to decompress the trigeminal nerve may be the treatment of choice.

trigeminal neuropathy. May be caused by a number of rare conditions, usually manifested by loss of facial sensation or weakness jaw muscles. Such conditions can be: tumors of the middle cranial fossa, trigeminal nerve, tumor metastases to the base of the skull, lesions of the cavernous sinus (with damage to the first and second branches of the V nerve) or superior palpebral fissure (with damage to the first branch of the V nerve).

Facial nerve (VII)

Damage to the VII cranial nerve or its nucleus leads to weakness of the muscles of the half of the face, which extends to the muscles of the forehead and the circular muscle of the eye; if nerve damage occurs in the fallopian canal, there is a loss of taste sensitivity in the anterior 2/3 of the tongue and hyperacusis may occur; if the nerve lesion occurs in the internal auditory canal, the auditory and vestibular nerves are involved, while lesions at the level of the pons involve the abducens nerve and very often pyramidal path. Damage to the peripheral nerve with incomplete recovery can lead to diffuse prolonged contracture of the affected facial muscles, sometimes combined with synkinesia of other groups of facial muscles and muscle spasms.

Bell's palsy. The most common form of idiopathic paralysis of the facial muscles, found annually in 23 out of 100,000 people. muscle weakness develops in 12-48 hours, sometimes it is preceded by pain behind the ears. Complete recovery occurs in 80% of patients within a few weeks or months. Treatment includes eye protection during sleep; prednisone (60-80 mg/day for 5 days, tapered over the next 5 days) may be effective, but the efficacy of this drug has not been fully established.

Hunt Syndrome. Caused by the herpes zoster virus when it affects the geniculate ganglion; differs from Bell's palsy in the presence of vesicular lesions in the pharynx, external auditory canal, and other parts of the outer integument of the skull.

Acoustic neuroma. Often compresses the VII nerve.

Tumor or infarction of the pons. They can cause weakness of the muscles of the face due to damage to the motor neurons of the nucleus of the facial nerve.

Bilateral facial diplegia. May develop in the syndrome Guillain-Barre, sarcoidosis, Lyme disease and leprosy.

Facial hemispasm. May occur either as a result of Bell's palsy, in processes that irritate the facial nerve (acoustic neuroma, aneurysm of the basilar artery, or aberrant nerve vascular compression), or as an idiopathic disease.

Blepharospasm. Involuntary recurrent spasm of the eyelids of both eyes, occurring in the elderly, sometimes in combination with spasm of other muscles of the face. Can pass on its own. Treatment: in severe cases decompression of the facial nerve or its section. According to the latest data, local injection of botulinum toxin into the orbicular muscle of the eye has proven to be effective, even with repeated treatment.

Vestibulocochlear nerve (VIII)

Vertigo caused by damage to the vestibular part of the VIII cranial nerve is described in Ch. 10. Lesions of the auditory nerve cause hearing impairment, which can be conductive, occurring when the sound-conducting apparatus is damaged as a result of a structural anomaly of the external auditory canal or middle ear due to a tumor, infection, injury, etc., or sensory-neural, arising from damage to the sound-perceiving apparatus due to damage to the hair sensory cells of the organ of Corti as a result of exposure to excessive noise, viral infections, ototoxic drugs, fracture of the temporal bone, meningitis, cochlear otosclerosis, Meniere's disease, or damage to the auditory nerve, resulting mainly from tumors of the cerebellopontine angle; or vascular, demyelinating, or degenerative diseases affecting the central auditory pathways. Stem auditory evoked potentials are a sensitive and accurate testing method for differentiating sensory from neural hearing loss. Audiometry allows you to distinguish conductive hearing loss from sensory neural. Most patients with conduction and asymmetric sensorineural hearing loss require a CT scan of the temporal bone. With sensory-neural hearing loss, electronystagmography and a caloric test should be performed.

Glossopharyngeal nerve (IX)

Glossopharyngeal neuralgia. paroxysmal, strong pain in the region of the tonsil, aggravated by swallowing. There are no pronounced sensory or motor disturbances. Treatment with carbamazepine or phenytoin is often effective, but surgical transection of the IX nerve near the medulla is sometimes necessary. Other diseases that damage this nerve include: herpes zoster, compression neuropathy when combined with vagus or accessory nerve palsy and due to a tumor or aneurysm in the jugular foramen.

Vagus nerve (X)

The defeat of the vagus nerve causes dysphagia and dysphonia. Unilateral lesions cause drooping of the soft palate, loss of the gag reflex and fluctuation of the lateral pharyngeal wall like a "curtain", the patient's voice becomes hoarse, nasal. Diseases that affect the vagus nerve include diphtheria (a toxin), neoplastic and infectious processes in the membranes, tumors and vascular lesions of the medulla oblongata, compression of the recurrent laryngeal nerve due to an intrathoracic process.

Hypoglossal nerve (XII)

The XII cranial nerve innervates the ipsilateral muscles of the tongue. Lesions that impair nerve function can be localized in the brainstem (lesion of the motor nucleus in tumors, poliomyelitis, diseases of motor neurons), along the nerve in the posterior cranial fossa (platybasia, Paget's disease), or in the hypoglossal canal.

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DISEASES OF THE PERIPHERAL NERVOUS SYSTEM
CRANIAL NERVE DISORDERS

trigeminal neuralgia

Trigeminal neuralgia is a disease manifested by repetitive short attacks of intense pain of a shooting nature in the zone of innervation of one or more branches of the trigeminal nerve.
Etiology. There are primary (idiopathic) and secondary (symptomatic) forms of trigeminal neuralgia. Idiopathic trigeminal neuralgia most often occurs in middle and old age and in some cases is due to compression of the nerve root by an elongated or dilated vessel. The cause of symptomatic neuralgia may be herpes zoster, aneurysm or arteriovenous malformation, multiple sclerosis, tumors of the trunk and base of the skull, diseases of the dental system, craniocerebral trauma, inflammatory lesions of the paranasal (paranasal) sinuses or temporomandibular joint, vasculitis, diffuse connective tissue diseases, etc.
Clinical picture. Idiopathic trigeminal neuralgia is manifested by short attacks of unilateral, very intense shooting pains, most often in the zone of innervation of the maxillary (maxillary teeth, upper jaw, zygomatic region) and mandibular (mandibular teeth, lower jaw) nerves (second and third branches of the trigeminal nerve) . Attacks last from a few seconds to several minutes and are repeated many times (up to 100 times a day), sometimes forming short series. They occur spontaneously or are provoked by chewing, talking, grimacing, shaking the head, touching the face, shaving, brushing the teeth. The pain may be so severe and sudden that the patient shudders (hence the term "pain tic"). On examination, usually no decrease in sensitivity is detected, but trigger points are found in the region of the wing of the nose, cheeks, gums, touching which provokes an attack of pain.
Symptomatic neuralgia should be suspected in cases where the disease begins before the age of 40, the pain does not have a typical localization, in particular, it is observed in the region of the ophthalmic (forehead, eye) nerve (the first branch of the trigeminal nerve), persists in the interictal period, and upon examination, decreased sensitivity on the face, weight loss, weakness of masticatory muscles and other focal neurological symptoms. Unilateral numbness of the chin and lower lip is a formidable symptom that may indicate a tumor infiltration of the mental nerve (for example, in breast cancer, prostate cancer, multiple myeloma).

Treatment.

Neuropathy of the facial nerve

Neuropathy of the facial nerve - an acute lesion of the facial nerve (VII), manifested by unilateral paresis of facial
muscles.

Etiology and pathogenesis.

clinical picture.

With idiopathic neuropathy of the facial nerve, in about half of patients, the development of paralysis is preceded by pain in the parotid region. Weakness of facial muscles increases over several hours, sometimes within 1-3 days. The face becomes asymmetrical, the skin folds on the side of the lesion are smoothed out, the corner of the mouth drops, the patient cannot raise an eyebrow, wrinkle his forehead, close his eyes, puff out his cheek, whistle; when the teeth are bared, the oral fissure is drawn to the healthy side. On the affected side, the palpebral fissure is wider, when squinting the eyelids do not close, and as a result of the fact that the eyeball is retracted upward, a white strip of sclera remains visible (lagophthalmos - "hare's eye"). AT lung case paresis of the circular muscle of the eye with a strong squeezing of the eyelashes does not completely "hide" in the palpebral fissure (a symptom of eyelashes). Due to paresis of facial muscles, speech becomes slurred. During chewing, the patient may bite his cheek, food gets stuck between the cheek and gum, liquid food pours out of the corner of the mouth.
The general condition of the patient does not suffer. Often, patients complain of discomfort in the paralyzed half of the face, but objectively changes in sensitivity are not detected. In most cases, lacrimation is noted, which is explained by the fact that, due to the weakness of the circular muscle of the eye and rare blinking, the lacrimal fluid accumulates in the lower conjunctival sac, and is not distributed evenly over the surface of the eyeball. In a small part of patients, dry eyes occur - with damage to the nerve before the fibers leave it to the lacrimal glands. Almost half of the patients have a decrease in taste in the anterior two-thirds of the tongue as a result of damage to the fibers of taste sensitivity, which are part of the facial nerve. In some patients, hyperacusis develops - heightened hearing, painful sensitivity to sounds, due to paresis of the stapedius muscle, which stretches the eardrum.
With Bell's palsy, in 80% of cases there is a complete spontaneous recovery of functions and only in 3% of patients the symptoms of the lesion do not regress, which usually suggests the presence of a tumor or other causes of the disease. The prognosis is critically dependent on the depth of damage. nerve fibers. If the myelin sheath is damaged, recovery can be expected within 3-6 weeks; if axons are damaged, nerve regeneration can last 3-6 months. In the latter case, recovery may be incomplete and the likelihood of complications increases dramatically - synkinesis, contractures, "crocodile tears" syndrome. During regeneration, axons form processes that grow to denervated muscles. A direct result of this process is pathological synkinesis - the simultaneous contraction of several muscles innervated by processes from one axon (an example is closing the eye when trying to smile). "Crocodile tears" - lacrimation during meals - are autonomic synkinesis resulting from the germination of salivary fibers to the lacrimal glands.

Treatment.

Facial hemispasm

Facial hemispasm is a condition manifested by bouts of involuntary clonic and tonic muscle contractions that are innervated by the facial nerve.

Etiology and pathogenesis.

clinical picture.

Most often, middle-aged people are ill. The spasm usually starts in the orbicularis oculi and then spreads to the middle and lower parts of the face. Between spasms, the face remains symmetrical, but sometimes there is a slight weakness of the mimic muscles on the side of the spasm. Hemispasm usually persists throughout life, gradually progressing over the years. But occasionally there are spontaneous remissions. To clarify the diagnosis, magnetic resonance imaging (MRI) or computed tomography (CT) with contrast is performed.
Treatment is carried out mostly on an outpatient basis. In some patients, antiepileptic drugs (carbamazepine, difenin, clonazepam, valproic acid) reduce hyperkinesia. If they are ineffective, surgical treatment (nerve decompression) is possible, as well as repeated injections of botulinum toxin into the involved muscles.

Vestibular neuronitis

Vestibular neuronitis is a lesion of peripheral vestibular neurons and the vestibular part of the vestibulocochlear nerve, manifested by acute dizziness, repeated vomiting, vestibular ataxia, followed by gradual recovery.
Etiology and pathogenesis remain unclear. In some cases, an upper respiratory tract infection is noted several weeks before the onset of the disease, indicating a possible viral nature diseases. It is assumed that the autoimmune process provoked by infection plays an important role in the pathogenesis of the disease.
Clinical picture Characterized by sudden severe rotational dizziness, nausea, repeated vomiting. Hearing loss and other neurological symptoms are absent. The slightest movement of the head increases dizziness, so patients sometimes deliberately support their head with their hands. Severe dizziness with repeated vomiting usually lasts no more than 3-4 days, but full recovery occurs within a few weeks, although in older people it may take several months. Occasionally, after a few months or years, relapses occur.

Treatment.

• anticholinergics, such as scopolamine;
• antihistamines, such as diphenhydramine, diprazine (pipolphen), meclizine (bonin), dimenhydrinate (dedalone);
• benzodiazepines, eg diazepam (Relanium), lorazepam (Merlit), clonazepam (Antelepsin);
• antipsychotics, eg etaperazine, meterazine, thiethylperazine (Torecan);
• antiemetics, including metoclopramide (Cerucal) and domperidone (Motilium).

Immediately after the condition improves (usually after a few days), these drugs are canceled and vestibular gymnastics becomes the basis of treatment. A serious mistake is the long-term and irrational use of these funds, which slow down compensation processes. Early mobilization of the patient and a special complex of vestibular gymnastics, thanks to which the patient develops the ability to control his movements with the help of vision, are of decisive importance in restoring the functions of the vestibular system. Exercises are done first.
in bed, and then, as the symptoms regress, in a standing position or in motion. Performing movements that cause slight dizziness, also speeds up compensation processes. Coordinated movements of the eyeballs, head, torso, which the patient first performs while lying down, then sitting, standing and, finally, when walking, contribute to the reconfiguration of the vestibular system and speed up recovery.

Neuralgia of the glossopharyngeal nerve

Neuralgia of the glossopharyngeal nerve (IX) is a rare disease manifested by bouts of intense pain in the depths of the oral cavity, the root of the tongue, and the tonsils.

Etiology and pathogenesis.

clinical picture.

The disease is manifested by short-term bouts of pain in the depths of the oral cavity, the root of the tongue, the tonsils. Sometimes the pain radiates to the ear and neck. Often an attack is provoked by swallowing (especially chilled liquids), coughing, chewing, talking, or yawning. Pain can also be elicited by touching the soft palate or tonsils, sometimes by pressure on the tragus. The attack lasts a few seconds or minutes and may be accompanied by bradycardia, a drop in blood pressure, and sometimes fainting. Decreased sensitivity and paresis is not detected. Spontaneous remissions from several months to several years are often observed.
Treatment is carried out with antiepileptic drugs, as in trigeminal neuralgia. If medical therapy fails, resort to surgical intervention(microvascular decompression, percutaneous thermocoagulation, or nerve root transection).

M. Victor, J. B. Martin

The cranial nerves are susceptible to lesions that rarely involve the spinal nerves. peripheral nerves and are therefore considered separately. This chapter describes the main syndromes caused by dysfunction of the cranial nerves. Damage to the cranial nerves, accompanied by disorders of taste, smell, vision, oculomotor disorders, dizziness and deafness, are also discussed in Ch. 13, 14 and 19.

Olfactory nerve

Syndromes of anosmia, ageisia and related disorders of smell

(see ch. 19)

optic nerve

Syndrome of transient monocular blindness (amaurosis fugax)

(See also ch. 343).

Definition. The term "amaurosis fugax" is used to characterize bouts of transient, painless loss of vision in one eye. Often they are recurrent. (The term "amaurosis" is used to define blindness of any etiology, in contrast to "amblyopia", which refers to visual impairment due to damage not to the eyeball itself, but to other structures.)

Clinical manifestations. Amaurosis fugax is a fairly common clinical symptom indicative of transient retinal ischemia, usually associated with homolateral stenosis of the internal carotid artery or retinal embolism. In some cases, the cause of the symptom cannot be determined.

Characteristically rapid, within 10-15 s, the development of blindness. Usually the patient reports a smooth, uniform and painless darkening of the visual field of one eye until then. until complete blindness sets in. In some cases, the narrowing of the field of view begins with the lower areas. Blindness persists for a few seconds or minutes, sometimes longer, then slowly dissipates and the patient's vision is restored to its previous level. Sometimes only generalized blurring, blurred vision is noted, and not its complete loss or involvement of only one segment of the visual field. Many patients who have had amaurosis fugax as a result of carotid stenosis also have transient attacks of contralateral hemiparesis. However, the simultaneous appearance of visual impairment and symptoms of damage to the cerebral hemispheres on the same side is not so common. It is assumed that in this case the leading role belongs to multiple microemboli, which block the small vessels of the brain, but do not necessarily lead to clinical symptoms. Immediately after the attack of amaurosis fugax, changes can be detected on the EEG.

Differential Diagnosis. Transient visual loss associated with migraine is another option. It is often preceded by indefinite flashes of light (photopsia) or the appearance of bright, blinding zigzag lines ( atrial scotoma), which move across the field of view for several minutes, leaving behind defects in the form of scotomas or hemianopia. A patient with migraine may complain of blindness in one eye, but on examination, the defects turn out to be bilateral and homonymous, that is, they capture the corresponding halves of both visual fields. These symptoms indicate involvement in the pathological process of the visual cortex of one of the occipital lobes. With the so-called vertebrobasilar migraine, in which neurological symptoms indicate disorders in the basin of the basilar artery, transient visual disturbances can capture the whole or both visual fields.

Treatment. Amaurosis fugax is most often a manifestation of a homolateral carotid lesion. Attention should be paid to carotid murmurs (if detected) and in each case, using non-invasive methods, assess carotid blood flow and arterial lumen diameter. The question of when to make the decision to perform angiography is discussed in Chap. 343. The final choice of treatment tactics is determined by the results of these studies. In the absence of pathological changes in the carotid artery, efforts should be made to search for another source of emboli (heart or aorta). Amaurosis fugax may be a manifestation of central retinal artery occlusion or anterior ischemic optic neuropathy due to giant cell arteritis or a non-inflammatory (atherosclerotic) lesion. With giant cell arteritis, ESR is usually increased (see Chapter 269).

Syndrome of retrobulbar optic neuropathy or retrobulbar neuritis

Definition. This syndrome is characterized by rapid, within hours or days, the occurrence of visual disturbances in one or both eyes. In the latter case, the dysfunction of the organ of vision occurs simultaneously or sequentially from two sides. In idiopathic cases (i.e., when other causes of optic nerve damage have been excluded), vision loss is the result of acute demyelination of the optic nerve fibers.

Clinical manifestations. In most cases, the disease develops as follows. A child, teenager or young adult begins to notice a rapid deterioration in vision in one eye (the feeling of seeing objects as if through a veil or haze). This condition can progress to a significant reduction in vision (
A significant number of such patients (from 15 to 40%) develop symptoms of multiple sclerosis over the next 10-15 years, and with longer follow-up periods, even more (see Chapter 348). Less is known about children with retrobulbar neuropathy, but the prognosis for them is much more favorable than for adult patients. Multiple sclerosis is the most common cause of unilateral retrobulbar neuritis. Bilateral optic neuritis may precede an attack of transverse myelitis by several days or weeks. This combination is called visual neuromyelitis, or Devic's disease (see Chapter 348). Other causes of unilateral optic neuropathy include post-infectious or disseminated encephalomyelitis, posterior uveitis (sometimes with reticular cell sarcoma), vascular lesions of the optic nerve, tumors (optic glioma, Recklinghausen neurofibromatosis, meningioma, metastatic carcinoma), and fungal infections. .

differential diagnosis. Anterior ischemic optic neuropathy (ANN) is a condition caused by the cessation of the blood supply to the optic nerve against the background of atherosclerotic or inflammatory lesions of the ophthalmic artery or its branches. It is characterized by acute, painless loss of vision in one eye, usually accompanied by a high visual field defect. In severe cases, vision loss is complete and permanent. In the fundus, a pale edematous optic disc is found, surrounded by peripalillary hemorrhages with outlines resembling chips. Sometimes pallor and puffiness are visible only in one of the sectors of the disk. Changes from yellow spot and retinas are not identified.

During the examination, it is necessary to exclude temporal arteritis (see Chapter 269). In rare cases, microemboli cause occlusion of the posterior ciliary arteries and PINZ, for example, after operations on open heart or coronary artery bypass surgery.

Central retinal artery occlusion (CRAC) often presents with sudden blindness. In this case, the optic disc initially has normal view. The retina with signs of a heart attack is pale, with a prominent macular spot of the "cherry stone" type.

Treatment. Acute optic neuropathy due to demyelination usually resolves without specific treatment. With a pronounced deterioration in vision, prednisone is prescribed at a dose of 40-80 mg daily in fractional doses for 7-10 days in a row, with a gradual decrease in the dose over several days. Some clinicians recommend prescribing ACTH. There are no data on the effectiveness of any one treatment method.

Toxic-metabolic optic neuropathy

The simultaneous deterioration of vision in both eyes, accompanied by the appearance within a few days or weeks of central or centrocecal scotomas, is usually due to toxic or metabolic disorders, and not the demyelination process (see Chapter 349). Visual impairment during intoxication with methyl alcohol occurs suddenly and is characterized by the appearance of large symmetrically located central scotomas, as well as symptoms systemic lesion and acidosis (see ch. 171). The optic nerve and the outer segments of the retina, rods and cones suffer. Treatment is mainly aimed at correcting the acidosis.

Somewhat less damaging effects on the optic nerve are drugs such as chloramphenicol (chloramphenicol), ethambutol, isoniazid, streptomycin, sulfonamides, digitalis, ergot (Ergot), teturam (antabuse) and heavy metals.

Retinal damage and optic nerve atrophy can be caused by degenerative diseases. There are several types of hereditary optic nerve atrophy, among which the X-linked Leber type, which occurs in men, is the most common (see Chapter 350). An autosomal dominant form has been described congenital atrophy of the optic nerve of early childhood, as well as atrophy of the optic nerve in combination with diabetes mellitus and deafness. Senile macular degeneration can lead to vision loss and various forms retinitis pigmentosa (see Chapter 13).

bitemporal hemianopia syndrome

This type of visual disturbance is usually caused by suprasellar growth of a pituitary adenoma (often associated with dilation of the sella turcica), but may also be due to craniopharyngioma, saccular aneurysm of the circle of Willis, meningioma of the tubercle sella turcica (with normal sella turcica and an enlarged, indurated tubercle on radiographic images), and in rare cases, sarcoidosis, metastatic carcinoma, and Hand-Christian-Schuller disease (see Chapter 321). Crossing fibers from the nasal halves of the retina are affected.

Homonymous hemianopia syndromes (See Ch. 13)

visual agnosia syndrome

(See ch. 24)

Oculomotor, trochlear and abducens nerves

Syndrome of ophthalmoplegia

Paralysis of the VI or III nerve on the side of the pathological focus is quite often found in adult patients, and paralysis of the VI nerve occurs about twice as often. Isolated VI nerve palsy is often due to diabetes mellitus, neoplasms, and increased intracranial pressure. Paralysis of III, IV, VI cranial nerves can occur as a result of damage to their nuclei or fibers when leaving the bridge or midbrain or along the nerves through the subarachnoid space, cavernous sinus and superior orbital fissure. When the focus is localized at each of these levels, specific syndromes are observed (Table 352-1). Pontal glioma in children and metastatic tumor from the nasopharynx in adults can produce an isolated abducens nerve lesion. Tumors of the base of the brain (primary, metastatic, carcinomatosis of the membranes) cause selective paralysis of the oculomotor nerves. In addition, trauma, ischemic nerve infarction, and aneurysms of the circle of Willis can be causes of paralysis of the VI or III nerves. Acute development of IV nerve palsy is relatively rare and is usually caused by trauma. In all cases of selective paralysis of the eye muscles, it is necessary to exclude exophthalmic ophthalmoplegia (Graves' disease) and myasthenia gravis. With lesions of the III nerve caused by its compression by an aneurysm, a tumor, or a hernial protrusion of the temporal lobe, an early symptom is pupil dilation, which is explained by the peripheral localization of papilloconstrictor fibers. In the case of a third nerve infarction, accompanied by pain in or around the eye and observed in diabetes mellitus or, less commonly, in cranial arteritis, the pupil, as a rule, remains intact. Patients in whom the etiology of the disease has not been established require long-term follow-up to monitor the regression of neurological symptoms or identify indications for an urgent re-examination.

Sometimes children and adults have one or more attacks of paralysis of the eye muscles, in combination with a migraine that is typical in all other respects (migraine ophthalmoplegia). In this case, the muscles innervated by the oculomotor nerve are affected, less often by the abducens nerve. It is believed that intense vascular spasm of the artery supplying blood to the nerve causes transient ischemia. Arteriograms taken after the onset of paralysis usually do not show any abnormalities. In all cases, recovery occurs.

Painful ophthalmoplegia (Tholosa-Hunt syndrome) most often indicates the presence of a parasellar granuloma. The acute onset of unilateral or bilateral ophthalmoplegia and hypersomnia is observed with pituitary apoplexy. They may be accompanied by decreased visual acuity and symptoms of chiasm compression. The slow development of complete unilateral ophthalmoplegia is most often due to an enlarging aneurysm (in this case, the onset may be acute), a tumor, or inflammatory process in the cavernous sinus or in the region of the superior orbital foramen (Foy's syndrome - see table. 352-1). This syndrome initially often manifests itself as a lesion of the VI nerve.

Gaze paralysis or a combination of ophthalmoplegia with gaze paralysis, usually due to vascular, demyelinating or neoplastic processes in the brainstem, are discussed in Chap. 13.

Trigeminal nerve

The trigeminal nerve provides sensory innervation to the skin of the face and half of the upper half of the skull, as well as motor innervation to the masticatory muscles.

Syndrome of paroxysmal facial pain (trigeminal neuralgia, pain tic)

Definition. The most severe lesion of the trigeminal nerve is a painful tic - a condition characterized by excruciating paroxysms of pain in the lips, gums, cheeks or chin and, in rare cases, in the region of innervation of the ophthalmic branch of the Vth nerve. The disease is observed almost exclusively in middle-aged and elderly people. Pain rarely lasts longer than a few seconds or 1-2 minutes, but can be so intense that the patient shudders and winces from them, and therefore the term "tic" is used in the name. Paroxysms often recur both during the day and at night, sometimes for several weeks. Another typical feature It consists in provoking pain by stimulating effects on certain areas on the face, lips and tongue (the so-called trigger zones) and movements in these departments. Loss of sensitivity can not be detected. When studying the relationship between stimulating effects of stimuli on the trigger zone and pain paroxysm, it was found that tactile stimulation and, possibly, tickling, rather than pain and temperature effects, are most adequate to cause an attack. Usually, spatial and temporal summation of impulses is necessary to provoke an attack, but the onset of pain is preceded by a refractory period of up to 2-3 minutes.

The diagnosis of the disease is based on strict clinical criteria, and it must be distinguished from other forms of facial and head neuralgia, as well as pain due to lesions of the jaws, teeth or sinuses. Painful tic usually occurs without connection with any obvious reason; sometimes it serves as a manifestation of multiple sclerosis in young people and can be bilateral. Very rarely, it is combined with herpes zoster or a tumor. Sometimes the appearance of a painful tic may be due to an additional or pathologically tortuous artery in the posterior cranial fossa, causing irritation of the nerve or its root. Usually, however, mass processes such as aneurysms, neurofibromas, or meningiomas that affect the nerve cause decreased sensation (trigeminal neuropathy).

Treatment. Treatment for pain tics begins with pharmacotherapy. Carbamazepine is the drug of choice and is initially effective in 75% of patients. Unfortunately, about 30% of patients do not tolerate pain-relieving doses of the drug. Treatment with carbamazepine begins gradually with a single dose of 100 mg of the drug during meals, followed by an increase in dose to 200 mg 4 times a day. Doses in excess of 1200-1600 mg do not provide any additional beneficial results.

If medical therapy is ineffective, surgical treatment - ganglionosis and suboccipital craniectomy with trigeminal decompression should be recommended. Ganglionosis is a minor surgical procedure that involves a percutaneous injection of glycerol or ethanol, usually under local anesthesia. High-frequency nerve injuries are also widely used. The introduction of glycerol proved to be effective in many patients, but positive action comes on slowly and the pain may recur. High-frequency injuries stop pain in 80% of cases for 1 year and in 60% of cases for 5 years. But this procedure leads to partial numbness of the face and carries with it the risk of corneal denervation and secondary keratitis when exposed to the first branch of the trigeminal nerve with its neuralgia.

Suboccipital craniectomy is a major surgical procedure in which the patient must be hospitalized for about 1 week. It is effective in 80% of cases, but in 5% of cases it can lead to serious complications. Not all operated patients can detect vascular or other compression lesions of the trigeminal nerve. The most painful complication of all surgical interventions is anestesia dolorosa, or denervation hypersensitivity. This condition is difficult to treat. In this case, tricyclic antidepressants or phenothiazines are prescribed, which alleviate the condition only partially.

Trigeminal neuropathy

In addition to those already mentioned, several more factors can be detected that cause trigeminal neuropathy. At the same time, in most patients, sensitivity on the face decreases or weakness of the mandibular muscles appears. Deviation of the lower jaw when opening the mouth indicates weakness of the pterygoid muscles on the side to which the jaw deviates. Tumors of the middle cranial fossa (meningiomas), trigeminal nerve (schwannomas), and the base of the skull (metastases) can cause motor and sensory disturbances. With the localization of pathological processes in the region of the cavernous sinus, symptoms are observed that indicate involvement in the process of the first and second branches of the trigeminal nerve, and near the superior orbital fissure, the orbital branch of the V pair. Concomitant anesthesia of the cornea increases the risk of corneal ulceration (neurokeratitis).

The development of anesthesia and analgesia of the face after treatment with stilbamidine (Stilbamidine), previously used in the treatment of patients with Indian visceral leishmaniasis and multiple myeloma, is described. Convalescents may experience pain and itching. In rare cases, an idiopathic form of trigeminal neuropathy is observed. It is characterized by sensations of numbness and paresthesia, sometimes bilateral, as well as loss of sensation, but without signs of weakness of the lower jaw. As a rule, patients recover, but disturbing phenomena can persist for many months and even years. The defeat of the V nerve can be observed in leprosy.

A tonic spasm of the masticatory muscles, known as trismus, is characteristic of tetanus. Trismus may also be an idiosyncratic reaction in patients treated with phenothiazines. Less commonly, it accompanies diseases of the pharynx, temporomandibular joint, teeth and gums.

facial nerve

Syndromes of facial paralysis and facial spasm

VII cranial nerve innervates the facial muscles. Its sensory part is small (intermediate, vrisberg nerve), provides taste sensitivity to the anterior 2/3 of the tongue and, probably, conducts impulses from the skin of the anterior wall of the external auditory canal. Motor nucleus VII nerve lies in front and to the side of the nucleus of the abducens nerve. After leaving the bridge of the brain, the VII nerve enters the internal auditory canal along with the auditory nerve. Further, the nerve continues its course through the middle ear until it exits the skull through the stylomastoid foramen. Then it pierces the parotid salivary gland and is divided into separate branches innervating the muscles of the face.

A complete interruption of the facial nerve at the level of the stylomastoid foramen leads to paralysis of all the mimic muscles of the half of the face. At the same time, the corners of the mouth are lowered in the patient, skin folds on the face are smoothed out, frontal wrinkles are straightened, it becomes impossible to close the eyelids. When trying to close the eye on the paralyzed side, an upward turn of the eyeball is visible (Bell's phenomenon). The lower eyelid also sags, and therefore the lacrimal opening falls out of the conjunctiva, and tears flow down the cheek. Food accumulates between the teeth and lips, and saliva may drip from the corner of the mouth. The patient complains of immobility and numbness of the face, but there is no decrease in sensitivity and taste disorders.

When the pathological process is localized at the level of the middle ear, a loss of taste is found in the anterior 2/3 of the tongue on the side of the lesion. When n. stapedius breaks, hyperacusis occurs (painful perception of low sounds). Pathological foci in the internal auditory canal can also lead to the involvement of the adjacent auditory and vestibular nerves and cause deafness, tinnitus and dizziness. Intrabridge lesions, accompanied by paralysis of the mimic muscles, usually also affect the nucleus of the abducens nerve and often the cortico-spinal tract and sensory conductors.

With the preservation of peripheral paralysis of the facial nerve for a certain time and the onset, but incomplete recovery motor function there is a formation of contracture (actually - diffuse contraction) of the muscles of the face (hemifacial spasm). Palpebral fissure narrows, deepens nasolabial fold. Over time, the face and even the tip of the nose are drawn to the unaffected side. Attempts to carry out the movement of one of the groups of facial muscles lead to a contraction of all the muscles of the face (combined movements, or synkinesis). Facial spasms can be triggered by any movement of facial muscles, they occur unexpectedly and persist for some time (see below). The cause of other bizarre disorders may be abnormal regeneration of fibers of the VII nerve. If the fibers originally associated with the orbicular muscle of the eye pass to the innervation of the orbicular muscle of the mouth, then when the eyelids close, the mouth may shrink. In cases where the fibers originally associated with the mimic muscles later begin to innervate lacrimal gland, then with any functioning of the muscles of the face, for example, while eating, pathological lacrimation (crocodile tears) is observed. Another unusual facial synkinesis is characterized by the fact that when the lower jaw is lowered, the eyelids close on the side of the paralysis of the facial nerve (jaw-blinking synkinesis).

Table 352-1. Cranial Nerve Syndromes

Bell's palsy

Definition. The most common form of facial paralysis is idiopathic, i.e. Bell's palsy. It occurs in about 23 people per 100,000 annually, or 1 in 60-70 people throughout life. The pathogenesis of the disease is unknown. Sometimes at autopsy, only non-specific changes in the facial nerve were found, which, however, were not inflammatory, as they are commonly believed.

Clinical manifestations. Bell's palsy begins suddenly, weakness usually reaches its maximum severity after 48 hours. 1-2 days before the development of paralysis, the patient may feel pain behind the ear. Sometimes taste sensitivity is lost and hyperacusis is present. Some patients have mild pleocytosis. Up to 80% of patients recover within a few weeks or months. Electromyographic signs of denervation 10 days later are indicative of axonal degeneration and that regeneration occurs with a long delay and may be incomplete. Electromyography helps to differentiate a temporary conduction defect from an anatomical break in the course of nerve fibers. If during the 1st week of the disease the patient is diagnosed with incomplete paralysis, this serves as a favorable prognostic sign.

Treatment. Measures to protect the eyes during sleep, massage of weakened muscles and a splint that prevents the lower part of the face from lowering are shown. A course of prednisone starting at 60–80 mg daily for the first 5 days may be effective. In the next 5 days, the dose of the drug is gradually reduced. Surgical decompression of the facial nerve in its canal is recommended, but there is no data in favor of the effectiveness of this method. Moreover, its impact can be detrimental.

differential diagnosis. There are many other causes of facial paralysis. Tumors that grow into the temporal bone (carotid body, cholesteatoma, dermoid) can cause paralysis of the facial nerve, but they are characterized by a gradual onset and a progressive course. Hunt's syndrome - a form of herpes zoster with damage to the ganglion of the knee; manifested by deep paralysis of mimic muscles in combination with vesicular rashes in the pharynx, external auditory canal and other parts of the integument of the skull; often the VIII nerve also suffers. Acoustic neuroma often leads to paralysis of the facial nerve due to its local compression (see Chapter 345). Infarctions and tumors are frequently observed lesions of the bridge, accompanied by a break in the fibers of the facial nerve. Bilateral paralysis of facial muscles (facial diplegia) develops in acute inflammatory polyradiculoneuritis (Guillain-Barré disease) and a form of sarcoidosis known as uveoparotid fever (Heerfordt's syndrome). The Melkersson-Rosenthal syndrome is characterized by a rare triad of recurrent facial paralysis (and eventually persistent facial palsy), swelling of the face (especially in the lip area), and less permanently observed wrinkling of the tongue. Many causes have been proposed for this syndrome, but none have yet been confirmed. The facial nerve is often affected in leprosy.

The mysterious disease is Romberg's facial hemiatrophy. It occurs mainly in women and is characterized by the disappearance of fat in the dermal and subcutaneous tissues on one side of the face. These changes usually appear in adolescents or in individuals young age and slowly progress. At the developed stage, the face becomes elongated, emaciated, and the skin is thin, wrinkled, with a brown tint. Facial hair is often depigmented and falls out, the sebaceous glands atrophy. Muscle and bone tissue, as a rule, remain intact. Sometimes atrophy becomes bilateral. This condition is a form of lipodystrophy, and localization of changes within the dermatome suggests that it is associated with some neural trophic factor of unknown nature. Treatment consists of transplantation of the skin and subcutaneous fat using plastic surgery.

There are cases when the muscles of one half of the face may undergo irregular clonic contractions of varying severity (hemifacial spasm). This condition may be a transient or permanent consequence of Bell's palsy, but occasionally occurs de novo as a benign phenomenon in adults. Hemifacial spasm may be due to an irritative lesion of the facial nerve (eg, acoustic neuroma, an aberrant artery leading to nerve compression that can be relieved by surgery, or an aneurysm of the basilar artery). However, in the most common form of hemifacial spasm, the cause and pathological basis of the disease are unknown. Small fibrillar twitches of facial muscles (facial myokymia) can be caused by plaque of multiple sclerosis. Bilateral involuntary recurrent spasm of the eyelids (blepharospasm) occurs in elderly patients as an isolated syndrome or in combination with facial muscle spasm of varying severity. Relaxing and sedative drugs are not very effective, but in many patients these disorders regress spontaneously. In a very severe and persistent course, intracranial differentiated dissection of individual branches of the facial nerve or decompression of the nerves (from the vessels) can be recommended. In recent years, cases of successful treatment of patients by local injection of botulinum toxin into the eyelids have been described.

Taste disorders are discussed in Chap. 19.

All these variants of nuclear or peripheral paralysis of the facial nerve should be distinguished from its supranuclear lesion. In the latter case, the frontalis and orbicularis oculi muscles are less affected than the musculature of the lower face, since the muscles of the upper face are innervated by corticobulbar tracts from the motor areas of both hemispheres, while the muscles of the lower face are innervated only by nerves from the opposite hemisphere of the brain. With a supranuclear lesion, there may be dissociation between emotional and voluntary movements carried out by the muscles of the face, and often it is also accompanied by varying degrees of paralysis of the arms and legs or aphasia (with involvement of the dominant hemisphere).

Vestibulocochlear nerve

The VIII cranial nerve has two components - vestibular and auditory. Symptoms of damage to the vestibular (vestibular) part are discussed in Chap. 14 and in this section. The cochlear (auditory) part and signs of its defeat are described in Ch. 19.

Syndrome of benign recurrent vertigo

Meniere's syndrome. Definition and clinical manifestations. The disease, or Meniere's syndrome, is called recurrent dizziness, accompanied by a sensation of tinnitus and hearing loss. During the first attack (or initial attacks) of vertigo recent symptoms may be absent, but they appear as the disease progresses and the severity of attacks increases. In milder forms, patients complain more of a feeling of discomfort in the head, slight unsteadiness and difficulty concentrating than of dizziness, and therefore these disorders are often attributed to anxiety or depression. Because the hearing loss is incomplete, the phenomenon of recruitment can be demonstrated (see Chapter 19).

Meniere's disease often begins after the age of forty, but it can also be diagnosed in young and old people. Pathological changes consist in the expansion of the vessels of the endolymphatic system, which leads to the degeneration of sensitive vestibular and auditory ciliated cells. The relationship of these pathological changes with paroxysmal disorders of the labyrinth function remains unclear.

Treatment. During an attack, resting in bed is most helpful, as the patient is usually able to choose a position in which dizziness is minimal. In the case of a more protracted course, dimenhydrinate, cyclizine (Cyclizine) or meclizine (Meclizine) at doses of 25-50 mg 3 times a day are effective. During treatment, a low-salt diet is indicated, the significance of which is difficult to assess. Light sedatives reduce anxiety in patients between attacks. Hearing loss is usually unilateral and progressive, and when it becomes complete, the attacks of dizziness stop. However, the course is characterized by variability, and if the attacks are severe, then a stable improvement can be achieved with the help of surgical destruction of the labyrinth or intracranial dissection of the vestibular (vestibular) part of the VIII nerve.

Benign positional vertigo. Other labyrinth dysfunctions are characterized by paroxysmal dizziness and nystagmus in certain critical head positions. This is Barany's positional vertigo of the so-called benign paroxysmal type (see Chapter 14). In refractory cases in which seizures continue, the vestibular exercises described by Lee may be effective.

Differential diagnosis of dizziness. There are many other causes of acute dizziness. These are purulent labyrinthitis, which is a complication of meningitis, severe labyrinthitis due to middle ear infection, "toxic" labyrinthitis due to drug intoxication (eg, alcohol, quinine, streptomycin, gentamicin, and other antibiotics), motion sickness, trauma, and hemorrhage in the inner ear. In these cases, the attacks of vertigo are longer than in the relapsing form, but otherwise the symptoms are similar. Streptomycin and gentamicin can cause damage to sensitive hair cells in peripheral vestibular organs and lead to persistent balance (and hearing) disorders, especially in elderly patients.

A dramatic clinical syndrome characterized by the sudden onset of severe dizziness, nausea and vomiting without tinnitus and hearing loss. The vertigo continues for days or weeks, and the labyrinth function is always affected on one side. This syndrome can be explained by occlusion of the labyrinthine branch of the internal auditory artery, but to date, no pathological and angiographic confirmation of this hypothesis has been received.

Dizziness with damage to the vestibulocochlear nerve is observed in diseases accompanied by nerve involvement in the pyramid of the temporal bone or at the level of the cerebellopontine angle. Such dizziness resembles labyrinthine dizziness, but it is less severe and less often paroxysmal. It is also possible to damage the auditory part of the VIII nerve, which explains the frequent combination of dizziness with tinnitus and hearing loss. The function of the VIII nerve can be disturbed by tumors of the lateral sinus (especially acoustic neuroma), less often - inflammation of the meninges in this area, and occasionally - a pathologically altered vessel that compresses the nerve.

The terms "vestibular neuronitis" and "benign recurrent vertigo" refer to a clinical syndrome that occurs mainly in middle-aged and young (sometimes children's) people. This syndrome is characterized by sudden onset of dizziness, nausea, and vomiting without hearing loss. Attacks are short-lived, but after them the patient has mild positional dizziness for several days. Such episodes can develop only once or recur, proceeding with varying degrees of severity. Their cause is unknown. Treatment is similar to that for Meniere's disease.

A specific form of paroxysmal vertigo affects children. Seizures occur with good general condition health, begin suddenly and proceed for a short time. Vivid manifestations are pallor, profuse sweating, immobility, sometimes vomiting and nystagmus are noted. There is no connection of these symptoms with the positions and movements of the head. Seizures recur but tend to spontaneously stop after a few months or years. Pronounced changes are detected during a caloric test, which demonstrates a one- or two-sided violation of the vestibular function, often remaining after the attacks have stopped; cochlear function, meanwhile, remains intact. The pathological basis of the disease has not been established.

Cogan described a peculiar syndrome in young people in which interstitial keratitis, dizziness, tinnitus, nystagmus, and rapidly progressive deafness were observed. The prognosis for recovery and restoration of the function of the organs of vision is favorable, but hearing loss is usually persistent. The cause and pathogenesis of the disease have not been elucidated, but some patients later develop aortitis and vasculitis resembling periarteritis nodosa.

Glossopharyngeal nerve

Glossopharyngeal neuralgia syndrome

Glossopharyngeal neuralgia resembles trigeminal neuralgia in many ways. The pain is severe and paroxysmal in nature; it is localized in the throat near the tonsillar fossa. Some patients complain of pain in the ear or it radiates from the throat to the ear due to the involvement of the tympanic branch of the glossopharyngeal nerve (Jacobson's nerve). Painful spasms can be provoked by swallowing. Symptoms of sensory and motor deficits are not detected. Describe violations by of cardio-vascular system in the form of bradycardia and hypotension. Treatment is recommended to begin with the appointment of carbamazepine or phenytoin, and in case of their ineffectiveness, dissection of the nerve near the medulla oblongata is fully justified.

In very rare cases, herpes zoster affects the glossopharyngeal nerve. Glossopharyngeal neuropathy in combination with paralysis of the vagus and accessory nerves can be caused by a tumor or aneurysm located in the region of the posterior cranial fossa or jugular foramen. This symptom complex consists of dysphonia due to paralysis of the vocal cord, some difficulty in swallowing, deviation of the soft palate to the healthy side, anesthesia of the posterior pharyngeal wall, weakness of the upper part trapezius muscle and sternocleidomastoid muscle (see Table 352-1, jugular foramen syndrome).

Nervus vagus

Syndrome of dysphagia and dysphonia

A complete interruption of the intracranial part of one vagus nerve leads to the characteristic picture of paralysis. The soft palate sags on the affected side and does not rise during phonation. The gag reflex on the affected side disappears, as well as the "veiling" movement of the lateral wall of the pharynx, while the palatine arches are displaced medially when the sky rises during the pronunciation of the sound "a". The voice is hoarse, with a slight nasal tinge, and the vocal cord remains motionless, maintaining a mid-position between abduction and adduction. Loss of sensation in the external auditory canal and the back of the outer ear can be observed. Changes in the functions of internal organs are usually not detected.

A complete interruption of both vagus nerves is considered incompatible with life, and this statement seems to be true in cases where their nuclei in the medulla oblongata are affected in poliomyelitis and some other diseases. Meanwhile, blockade of the vagus nerves with procaine (novocaine) in the cervical region in the treatment of intractable asthma is not accompanied by complications. The pharyngeal branches of both vagus nerves may be affected in diphtheria; the voice takes on a nasal tone, and during the act of swallowing, fluid regurgitation occurs through the nose.

The vagus nerve may also be affected at the meningeal level by neoplastic and infectious processes, in the medulla oblongata with tumors and vascular lesions (for example, with Wallenberg's syndrome of lateral lesions of the medulla oblongata), as well as in diseases of the motor neuron. Inflammatory nerve damage can be observed with herpes zoster. Hoarseness and dysphagia in polymyositis and dermatomyositis, due to the direct involvement of the muscles of the larynx and pharynx, are often mistaken for signs of damage to the vagus nerves. Dysphagia is also seen in some patients with myotonic dystrophy (see Chapter 32 for a discussion of non-neurological forms of dysphagia).

The recurrent laryngeal nerves, especially the left one, are most often affected as a result of intrathoracic diseases. More common causes of isolated vocal cord paralysis are aortic arch aneurysm, left atrial dilatation, mediastinal and bronchial tumors, rather than intracranial pathological processes.

Having found paralysis of the larynx, the doctor must determine the localization of the lesion. If it is intramedullary, then other symptoms are usually found, for example, homolateral cerebellar dysfunction, loss of pain and temperature sensitivity on the side of the face of the same name with the focus and in opposite limbs, homolateral Horner's syndrome. The glossopharyngeal and accessory nerves are often also affected in extramedullary pathologies (see discussion of jugular foramen syndrome above). With extracranial localization of the focus in the posterior laterocondylar or retroparotid space, a combination of paralysis of the IX, X, XI and XII cranial nerves and Horner's syndrome is possible. Combinations of paralysis of these lower cranial nerves have several eponymous designations listed in Table. 352-1. If there is no loss of sensitivity in the region of the palate and pharynx, there is no weakness of the palate and dysphagia, this indicates that the lesion is located below the origin of the pharyngeal branches that leave the vagus nerve at a high cervical level; usually localization of the pathological process is the mediastinum.

hypoglossal nerve

The XII cranial nerve innervates the muscles of the tongue from its side. Processes that affect the motor nucleus can be localized at the level of the brain stem (tumor, poliomyelitis, motor neuron diseases), along the nerve in the posterior cranial fossa or in the canal hypoglossal nerve. There are isolated lesions of unknown etiology. Atrophy and fasciculations of the tongue develop weeks or months after its break.

Multiple cranial nerve palsies

One disease can cause damage to several cranial nerves at once. In such a situation, the main task is to determine the localization of the lesion - inside the brain stem or outside it. Foci located on the surface of the brainstem capture neighboring cranial nerves (often this happens sequentially) and later give mild signs of involvement of long sensory and motor conductors, segmental formations within the brainstem. The opposite statement is true for intramedullary, intrapontine and intramesencephalic pathological processes. The extramedullary lesion results in bone erosion and dilation of the openings through which the cranial nerves exit. Intramedullary processes affecting the cranial nerves often cause the development of alternating syndromes (symptoms of damage to the cranial nerves on one side and on the opposite - sensory and motor conductors).

Involvement of several cranial nerves outside the brainstem is often the result of trauma (sudden onset), local infections such as herpes zoster (acute onset), granulomatous diseases such as Wegener's granulomatosis (subacute onset), Behcet's disease, tumors, and growing saccular aneurysms ( chronic development). Successive involvement of the caudal group of cranial nerves produces tumors, including neurofibromas, meningiomas, chordomas, cholesteatoma, carcinomas, and sarcomas. Depending on the anatomical relationship, multiple cranial nerve palsies form a number of peculiar syndromes listed in Table. 352-1. It has been shown that the cause of some cases of multiple neuropathy of the cranial nerves is sarcoidosis, less often tuberculosis. cervical lymphadenitis. Malignant granuloma can also lead to simultaneous involvement of many cranial nerves, as can tumors of the nasopharynx, platybasia, basilar invagination of the skull, and Arnold-Chiari anomaly presenting in adults. When purely movement disorders without atrophy, the question of myasthenia gravis always arises (see ch. 358). Guillain-Barré syndrome is often accompanied by a bilateral lesion facial nerves(facial diplegia). In the Fischer variant of Guillain-Barré syndrome, paresis of the oculomotor nerves is observed in combination with ataxia and areflexia in the extremities. Wernicke's encephalopathy can cause severe ophthalmoplegia with concomitant stem symptoms (see Chapter 349).

Sometimes there is a benign idiopathic form of multiple involvement of the cranial nerves on one or both sides. The disease can relapse over the years, with subsequent recovery of varying degrees between exacerbations. This condition is called multiple cranial polyneuritis.

With paralysis of the third pair of cranial nerves, the mobility of the eyeballs is limited and / or pupillary reactions may be impaired. Among the symptoms are diplopia, ptosis, paresis of adduction of the eye and gaze up and down, mydriasis is possible. With changes in the pupil or an increase in the oppression of the patient's consciousness, urgent CT is indicated.

The reasons

Paralysis of the III pair of cranial nerves with the involvement of the pupil often occurs with aneurysms and transtentorial herniation, less often with meningitis involving the brain stem (for example, tuberculosis). A common cause of paralysis with preservation of pupillary functions is ischemia of the third pair of cranial nerves or the midbrain.

Symptoms and signs

Clinical manifestations include diplopia and ptosis. The affected eye may deviate outwards and downwards when looking directly; adduction is weakened: the eye does not cross the midline. Upward gaze is broken. The pupil may be normal or dilated; the direct or consensual response to light may decrease or disappear (efferent defect). Pupil dilation (mydriasis) may be an early sign.

Diagnostics

• Clinical examination.
• CT or MRI.

The differential diagnosis is made with intraorbital structural lesions that limit the mobility of the eye, affecting the path oculomotor nerve(Claude's sign, Benedict's sign), leptomeningeal tumor or infection, cavernous sinus disease (eg, giant aneurysm, fistula, or thrombosis), intraorbital lesions (eg, orbital mucormycosis) that restrict the movement of the eyeball, ocular myopathies (eg, hypothyroidism, mitochondrial disorders or polymyositis). Differential diagnosis can be made based only on clinical symptoms. The presence of exophthalmos or anophthalmos, a history of severe trauma to the orbit, or obvious inflammation in the orbital area suggests an intraorbital structural lesion. Orbitopathy in Graves' disease (ophthalmopathy) should be considered in patients with bilateral eye muscle weakness, paresis of upgaze or abduction, exophthalmos, eyelid retraction, eyelid lag when looking down, and a normal pupil.

CT or MRI is indicated. If, along with the expansion of the pupil, a severe headache suddenly occurs (possible rupture of the aneurysm) or worsening of the condition (possible herniation of the brain), urgent CT is indicated. If a ruptured aneurysm is suspected, if CT is unavailable or no blood is present, lumbar puncture, MR or CT angiography, or cerebral angiography is indicated. With the defeat of the cavernous sinus or with mucormycosis, for timely treatment, an MRI should be performed immediately.

Treatment

Treatment depends on the cause of the disease.

Damage to the IV pair of cranial nerves

With paralysis of the IV pair of cranial nerves, the superior oblique muscle of the eye suffers, which is manifested by gaze paresis in vertical plane, especially when cast.

Among the causes of paresis of the cranial nerves of the IV pair (trochlear nerve) are idiopathic lesions and craniocerebral injuries leading to uni- or bilateral disorders, and heart attacks due to the pathology of small arteries, less often - aneurysms, tumors (for example, tectorial meningioma, pinealoma) and multiple sclerosis.

Paralysis of the superior oblique muscle of the eye prevents normal adduction. The image is bifurcated vertically and slightly diagonally; accordingly, the patient has difficulty in looking down and inwards, such as when climbing stairs.

Examination may reveal slight limitation of eye movement.

Eye muscle exercises help restore binocular vision.

Damage to the VI pair of cranial nerves

With paralysis of the VI pair of cranial nerves, the lateral rectus muscle of the eye suffers, which disrupts the abduction of the eye. When looking straight ahead, the eye may be slightly adducted. Paralysis is usually idiopathic or is due to a heart attack, Wernicke's encephalopathy, trauma, infection, or increased intracranial pressure. An MRI and often a lumbar puncture and investigations for vasculitis are required to determine the cause of the lesion.

The reasons

Abducens nerve palsy often develops in small vessel occlusion, particularly in diabetes mellitus as a component of multiple mononeuropathy. It may be the result of nerve compression from lesions of the cavernous sinus (eg, nasopharyngeal tumors), orbit, or base of the skull. Paralysis can also develop due to increased ICP and/or traumatic brain injury. Other causes include meningitis, meningeal carcinomatosis, meningeal tumors, Wernicke's encephalopathy, aneurysms, vasculitis, multiple sclerosis, pontine stroke, and, rarely, headache associated with decreased ICP. In children, a respiratory tract infection can lead to recurrent paralysis. Sometimes the cause of paralysis of the VI pair remains unknown.

Symptoms and signs

Symptoms include binocular diplopia in the horizontal plane. When looking directly, the eye is somewhat adducted, which is due to the lack of compensation for the action of the medial rectus muscle. The eye is only slightly retracted, and even with maximum abduction, the lateral portion of the sclera is visible. With complete paralysis, the eye is not retracted beyond the midline.

Paresis develops as a result of nerve compression due to hematoma, tumor or aneurysm of the cavernous sinus, which is accompanied by severe headache, chemosis (edema of the conjunctiva), anesthesia in the innervation zone of the first branch of the V pair, compression of the optic nerve with loss of vision and paralysis of III, IV and IV pairs cranial nerves. The lesion usually develops on 2 sides, but is not symmetrical.

Diagnostics

The diagnosis of VI cranial nerve palsy is usually obvious, and the cause is usually determined during the examination. If pulsation of the veins is visible on the retina during ophthalmoscopy, then an increase in ICP is unlikely. CT scan is usually performed as available method, although MRI is more informative in terms of assessing the condition of the orbit, cavernous sinus, posterior cranial fossa and cranial nerves. If neuroimaging does not reveal any abnormalities, but there is suspicion of meningitis or increased ICP, then a lumbar puncture should be performed.

If vasculitis is suspected, it is necessary to determine the ESR, the levels of antinuclear antibodies and rheumatoid factor. In children, if there is no increase in ICP, a respiratory infection is suspected.

Treatment

Often, paralysis of the VI pair of cranial nerves decreases during the treatment of the underlying disease.