The topographic anatomy of the facial nerve is quite confusing, which is explained by the fact that it passes through the facial canal of the temporal bone, receiving and giving processes.
Where does it start?
It departs immediately from three nuclei: motor, secretory and sensitive fibers. Then, through the auditory opening, the facial nerve passes into the thickness of the temporal bone into the internal auditory canal. Here, the intermediate nerve is added to it, and a knee is formed on the bend of the channel, which, having taken the form of a node, gives the intermediate nerve the property of sensitivity. Anatomy of the facial nerve and scheme will be discussed in this article.
Process division
To enter the thickness of the parotid gland, the facial nerve is divided into separate processes: the lingual branch, the posterior ear nerve, the biliary network and the stylohyal branch. The intermediate gives such branches as the staple and stony nerves, connective tissue with tympanic weaving and the vagus nerve, and the terminal branch (tympanic string). The facial anatomy scheme is unique.
Branches
Once again, the facial nerve diverges in the thickness of the parotid gland, giving two main branches - a small lower and a powerful upper, which then also branch, and radially: up, forward and down to the muscles of the face. As a result, a parotid plexus is formed.
The facial nerve (the anatomy scheme will be presented in the photo) consists of the following parts:
- nerve trunk (more precisely, its processes);
- the space of the cerebral cortex, responsible for the work of the facial muscles;
- nuclei located between the bridge and the medulla oblongata;
- lymph nodes and a network of capillaries that feed nerve cells.
Functions
Anatomy of the facial nerve (diagram posted above) is considered. Now let's talk about its functions.
The main task of the facial nerve is to provide motor functions of the face. However, everything is complicated by the fact that before it branches into small parts, it is intertwined with the intermediate nerve and partially shares responsibilities with it. Through the internal auditory opening, they move into the tunnel of the facial nerve, where a knee is formed from it, which provides sensory support to the intermediate nerve.
The facial nerve is the basis of the motor activity of almost all the muscles of the face, however, in combination with the intermediate nerve, it has taste and secretory fibers.
The course of the fibers of the facial nerve is very interesting and should be carefully considered.
Facial Nerve Disorders
In case of malfunctions or infringement of the canal, paralysis of the motor muscles of the face can occur. Visually, its asymmetry is observed: the relaxed part has the effect of a mask due to its immobility, the eye on the affected side does not close, lacrimation intensifies due to the fact that the mucous membrane is irritated by dust, air, which, in turn, can cause conjunctivitis. The wrinkles on the forehead and the area around the nose and lips are straightened, the corners of the mouth are directed downward, a person cannot wrinkle his forehead.
In humans, the facial nerve is often affected (its branches, their anatomy and topography are presented in detail in the photo).
If for any reason the main, motor function is affected, then we are talking about peripheral paralysis. It is characterized by the following external signs: paralysis of the muscles responsible for facial expressions, complete asymmetry of the face, the speech apparatus is disturbed, fluid intake can be limited. If the nerve was affected at a time when it was located in the pyramidal bone, then in addition to the above symptoms, deafness and lack of taste sensations are also noted.
Neuritis is a neurological disease characterized by an inflammatory process. It can occur on the central part of the face and on the periphery. Symptoms depend on the site of the affected nerve. The disease develops either due to hypothermia (primary neuritis) or as a complication of other diseases (secondary).
It is characterized by an acute onset, the pain gives off behind the ear, after a few days there is an asymmetric face. Depending on the affected part, the symptoms may vary. With violations of the nucleus of the facial nerve, a person develops muscle weakness of the face. When the nerve is pinched in the area of the brain bridge, strabismus occurs, as well as paralysis of almost all of the muscles of the face. If the infringement occurred at the exit, the result will be a violation or short-term hearing loss. The facial nerve of a person is important. The structure, functions and problems have been studied for a long time.
In chronic otitis media, neuritis can have a concomitant character, arising due to inflammation in the middle ear, so it can be accompanied by a sensation of lumbago. If parotitis accompanies, then symptoms of general intoxication appear - chills, body aches, high fever.
Principles of Therapy
The treatment regimen of the facial nerve with infringements and inflammatory processes must necessarily be comprehensive. Therapy includes:
- diuretics that remove fluid from the network of capillaries;
- glucocorticosteroid drugs;
- vasodilator drugs;
- vitamins (usually group B).
Such treatment eliminates the root cause of the disease, since inflammation of the facial nerve is often the result of another disease, a secondary disease. Nerve ailments are most often accompanied by very unpleasant sensations, so the patient is prescribed analgesic drugs. For treatment to be faster and more effective, the facial muscles need to be completely relaxed.
The complex treatment also includes physiotherapeutic procedures. From the second week of the disease, it is allowed to apply facial massage and engage in physical therapy with a gradually increasing load. Surgery is very rare. Surgical treatment is indicated when neuralgia is congenital or arising after a mechanical injury. An operation of this kind is that improperly fused and torn nerve endings are stitched together. Surgical intervention is also legitimate if the medication is ineffective for six months (maximum eight months). If you ignore the process and do not use the listed methods of therapy, the facial muscles can completely atrophy without the possibility of recovery in the future. The only way out is surgical plastic surgery of the face, the material for which is taken from the victim's leg.
Conclusion
Thus, with timely access to medical care and proper treatment, recovery and recovery will be quite long, but the prognosis remains favorable. To avoid relapse, you need to monitor your health, avoid hypothermia and treat inflammatory processes such as tonsillitis, acute respiratory viral infections, etc.
We examined the facial nerve - anatomy and symptoms of damage, and also described the principles of treatment.