The facial nerve is a 7 pair of cranial nerves and consists primarily of motor fibers, which are responsible for the movement of facial muscles of the face. Each half of the face is innervated by its facial nerve. If the nerve is damaged, there is paresis (weakness of the muscles) or plethia (lack of movement) in mimic muscles. The term "neuralgia of the facial nerve" is not entirely correct, since neuralgia denotes nerve damage, which accompanied by severe pain syndrome, because sensitive sensory fibers are involved in the composition of the nerve. The facial nerve contains a small amount of taste, pain and secretory fibers, so the term "neuropathy" will be more correct.
Neuropathy of the facial nerve or, in another way, "Bell's paralysis" occurs in 25 people per 100 thousand. of the population. Men and women suffer equally often.
In 80% of cases it is not possible to identify the cause of the disease. In other cases, there are a number of predisposing and provoking factors:
The peak incidence falls on the autumn and spring period, when windy weather sets in and people do not wear hats.
- The compression of the facial nerve tumor.
- Infectious-inflammatory processes (otitis, parotitis) of a viral and bacterial nature.
- Traumatic nerve injury (injuries, fractures of the skull).
Under the influence of various factors there is a violation of microcirculation and the development of edema, which leads to compression of the nerve and impaired excitation in it.
To understand what the clinical picture of lesion of the facial nerve is, let us consider where it is located and for what it answers.
Between the bridge and the medulla oblongata are the nuclei of the facial nerve. The processes of the cells that form the nuclei are directed to the base of the brain, where they approach the temporal bone. In the temporal bone there is a channel of the facial nerve, along which the nerve passes, then it goes to the surface of the face through a silicic aperture, perforating the parotid salivary gland, next to the external auditory meatus. In the canal of the temporal bone branches from it, which innervate the taste receptors in the tongue, the lacrimal glands and the tympanic membrane. On the face, it is divided into several branches, which innervate the muscles of the face.
Thanks to the facial nerve, we can smile, screw up our eyes, wrinkle our forehead, inflate our cheeks, grimace, show an angry or joyful face, we can cry with tears, feel the taste of the tip of the tongue.
The levels of lesion of the facial nerve can be different, most lesions occur in the narrow canal of the temporal bone. As a rule, the neuropathy of the facial nerve develops sharply for a couple of hours, less often a day. A person has a smooth skin folds on his face, his face "hangs" on the side of defeat. A person can not wrinkle his forehead, squint his eyes (he remains open - a symptom of Bell), can not keep food in his mouth, as the muscles of the cheeks and lips become weak, loses the ability to raise an eyebrow. If you ask a person to curl his lips with a pipe or whistle, he can not do it. The cheek during the conversation swells (a symptom of the "sail"), the speech becomes muffled, the corner of the mouth is lowered down. Due to the weakness of the circular eye muscle, tear fluid accumulates, causing lacrimation.
If the fibers responsible for the lacrimal gland function, the dry eye develops. The taste sensitivity in the tongue may change, there may be pain in the parotid gland.
Define the degree of lesion of the facial nerve:
- Easy degree.
Paresis (weakness) of mimic muscles is weakly expressed, reveals itself upon careful examination. It can reveal a slight drop in the angle of the mouth, squeezing the eyelid with effort. My facial expression is preserved.
- Moderate degree.
Paresis of mimic muscles is noticeable, but does not disfigure the face. The eye closes with effort, the forehead can wrinkle.
- The medium-heavy degree.
There is a disfiguring asymmetry of the face. The forehead can not wrinkle, the eye is partially closed.
- Heavy degree.
Movement in the muscles of the face is barely noticeable. The eye practically does not close, the forehead does not move.
- Extremely severe degree of total plegia.
There are no movements on the affected side of the face. The most unfavorable prognosis in terms of restoring facial expressions.
Diagnostic measures include a number of laboratory and instrumental studies that are aimed at establishing the cause of the disease:
- Inspection neurologist.
- General blood analysis.
- ENMG (electromyography). The method allows to accurately determine the level of lesion of the facial nerve.
- Radiography of the temporal bone, paranasal sinuses (search for pathology of the ENT organs).
- MRI of the brain (search for a brain tumor, stroke or other processes).
Timely treatment begun in half the cases leads to complete recovery of the person. The later treatment is started, the worse the prognosis. Treatment only in a hospital; includes several areas:
- Drug treatment.
- Glucocorticosteroids (Prednisolone). The main treatment is aimed at removing the edema in the canal of the temporal bone and improving microcirculation, therefore, hormones are prescribed from the first days of the disease.
- Non-steroidal anti-inflammatory drugs (Meloxicam, Nyz). Used to relieve inflammation, reduce pain in the parotid region.
- Vitamins of group B (Kombilipen, Neurobion). Thanks to the vitamins of group B, the nerve tissue is restored much better and faster.
- Vasoactive drugs (Pentoxifylline). Improve microcirculation in the lesion focus.
- Metabolic means (Actovegin). Preparations of this group improve the trophism of the nerve fiber, contribute to a rapid recovery of the myelin sheath of the nerve.
- Eye drops and ointments. Are prescribed for dry eyes, prevent the development of inflammation of the cornea or ulceration.
- Antiviral drugs (Acyclovir). With the proven role of virus in the development of neuralgia of the facial nerve, these drugs are prescribed from the first days of the disease.
- Antibacterial drugs (Ceftriaxone). Used if the role of bacterial infection in the development of the disease has been proven.
- Anticholinesterase drugs (Neuromidine). Provide a better holding momentum from the nerve to the muscle. Appointed during the recovery period.
- Physiotherapy (electrophoresis). Physioprocedures, especially in the early recovery period, proved to be well established.
- Leukoplastyrnoe traction is used in order to prevent the muscles from getting used to the new position.
- Exercise therapy. Gymnastic mimic muscles should be held several times a day, regularly. To restore speech, you need articulatory gymnastics.
- Surgery. These are plastic surgeries that are aimed at replacing the facial nerve with other nerve fibers in the absence of results from other treatments.
Complete recovery occurs in most cases (70%). In other cases, the incomplete restoration of the work of facial muscles remains. Total plegy and severe degree have a low percentage of positive results after treatment. Some people develop muscle contractures, which are spasmodic muscles with involuntary twitchings and are accompanied by a severe pain syndrome in these muscles.
There are a number of unfavorable prognostic factors:
- A combination of facial nerve neuropathy with diabetes mellitus.
- Development of dry eyes.
- Elderly age.
- Hypertonic disease.
- Deep damage to the facial nerve according to ENMG.
Neuropathy of the facial nerve does not affect the general condition of the body, but it affects the social and psychological aspects of a person's life, disfiguring the face. Timely diagnosis and treatment in most cases lead to a complete recovery of the person and his return to normal activities.
The doctor-neurologist E. Lyakhova talks about facial nerve neuropathy:
Watch this video on YouTube