Paralysis of facial muscles

Pathognomonic for the paralytic lagophthalmus is Bell's symptom: when the patient tries to close the eyes, the eyelids on the diseased side do not close, and through the gaping eye gap it is seen that the eyeball is shifted upwards; while only the sclera remains visible. This syndrome is physiological, but in healthy people it is not visible because of the complete closure of the eyelids.

[1], [2], [3]

What causes paralysis of facial muscles?

The cause of persistent paralysis of facial muscles can be: neuritis of nonspecific and specific origin; damage to the skull base in case of accidental trauma; inflammatory diseases of the middle ear, damage to the external ear and jaws; surgical interventions in the area of the cerebellopontine angle, middle and inner ear, in the parotid region (mainly in connection with neoplasms); Bell's paralysis and congenital paralysis.

Symptoms of paralysis of facial muscles

Symptoms of paralysis of facial muscles are diverse due to the varying degrees of conduction disorders in the branches of the facial nerve. The more branches involved in the pathological process, the more severe the clinical picture. However, in almost all cases, the main complaints of patients are related to the presence of facial asymmetry and lacrimation.

In sharply expressed cases, they are joined by complaints of difficulty in eating, which sticks on the threshold of the mouth and does not enter the oral cavity without pushing a finger.

Some patients complain of the difficulty of pronouncing a number of sounds, especially labial ones, in view of the impossibility of retaining air in the mouth and creating an air jet of the necessary pressure.

In a number of cases, a mischief appears on the side of the lesion. Secondary deformations on the part of the jaws, nose, and auricle are also possible.

Objectively, there is a more or less pronounced amy of the affected half of the face. With total defeat of all branches of the facial nerve, the corner of the mouth is pubescent, the nose-labial fold is smoothed, the cheek is thickened, drooping and pastose, the lower eyelid and the eyebrow are lowered, the horizontal folds of the forehead are smoothed (on the side of the lesion), the wing of the nose is somewhat shifted down, the nostril is flattened, the tip the nose is shifted to a healthy side.

In cases where the paralysis of facial muscles occurs in childhood, at mature age, there may be dental-jaw deformations in the form of one-sided prognosis (laterognathia), combined with an open bite. This is due to the uneven pressure of the cheeks and lips of the paralyzed and healthy half of the face on the growing and developing jaws. In addition, the chewing process is carried out mainly at the expense of the healthy side, as a result of which there is a more intensive growth of the lower jaw and its lateral shift.

The eye slit on the side of the paralysis gapes even in a state of rest, since the lower eyelid is lowered and leaves a wide strip of sclera under the cornea exposed; sometimes the eyelid is sharply turned out, and its skin is thinned to the thickness of the tissue paper, which is explained by atrophy and dysfunction of the circular eye muscle and trophic disorders in the lower eyelid.

The free edge of the upper eyelid sometimes has not an ordinary arched shape, but an arcuate shape as a result of the traction of an intact muscle lifting the upper eyelid innervated by the oculomotor nerve and attached to the middle third of the upper eyelid. For the same reason, the thickness of the upper eyelid does not change.

The eyebrow on the side of the paralysis is lowered, which gives the patient a sullen and alienated appearance and limits the upper field of view.

In paralysis of facial muscles, there are three variants of Bell's symptom:

• the eyeball tilts upward and slightly outward (occurs most often);
• the eyeball deviates upwards and is considerably outward;
• the eyeball deviates by one of the following options - up and down; only to the inside; only outside; up, and then oscillates pendulum-like; very slowly outside or inside.

The described varieties of Bell's symptom are important when choosing the method of scleroblerefarrraphy according to ME Yagizarov.

On the healthy side of the face, the tone of facial muscles is usually slightly elevated. As a result, with a smile, laughter and eating, the face is very disfigured by increasing the degree of distortion to a healthy side. This puts a heavy imprint on the psychoemotional state of patients who tend to smile and laugh as little as possible, and even if they laugh, they shamefacedly cover their face with their palms or turn their faces so that the interlocutor does not see the sick side of the face.

The severity of the objective local and general status (especially of the mental) in the paralysis of the facial muscles is due to the prescription of the disease, the presence of additional burdening deformations from the nose, jaws, auricles, and atrophic and paralytic phenomena in the masticatory muscles innervated by the trigeminal nerve.

Diagnosis of paralysis of facial muscles

AA Timofeev and IB Kindras (1996) introduced the concept of the asymmetry coefficient (K) -the ratio of the displacement of the center of the length of the line of the mouth to the length of the line of the mouth in the state tension at a teeth grin ".

Methods of electromyography and classical electrodiagnostics have established that in most patients the asymmetry of the electro-activity of the neuromuscular system is sharply expressed: complete bioelectric silence on the side of the lesion and hyperelectroactivity on the healthy side. Galvanic excitability of muscles on the patient side is either not determined at all, or reduced to 60-75-90 mV (at a rate of 30-40); Chronaxy of the muscles under study on the diseased side also decreases 2-3 times.

[4]

Treatment of paralysis of facial muscles

Operative methods used to treat paralysis of facial muscles can be divided into 3 groups:

• I - operations, statically or kinetically correcting the asymmetry of the face;
• II - operations, to some extent restoring the contractile function of the paralyzed side of the face;
• III - operations on the deformed mandible (elimination of unilateral prognosis).

The first group (corrective) operations include the following.

1. Various ways of static suspension or pulling to the zygomatic arch of the pubescent and mixed in the opposite side of the corner of the mouth (fascia of the thigh, bronze wire, thick silk threads impregnated with ferric chloride, a lot of silk threads, polyamide thread or lavsan mesh stripe, etc.).
2. Kinetic suspension of the dropped tissues of the corner of the mouth to the coronoid process, for example, lavsan threads.
3. Local-plastic surgery in the form of excision of excess stretched and flabby facial skin, narrowing of the enlarged ocular gap, scleroblopharoraphraphy according to Yagizarov's method, displacement of the lowered corner of the mouth to the top, etc.
4. Corrective operations on the healthy side, aimed at weakening the function of healthy facial muscles. This is achieved by crossing the branches of the facial nerve on the healthy side or turning off the function of the individual facial muscles on the healthy side (intersecting them with the subsequent resection of the muscle abdomen).

The second group includes the following operations.

1. Muscular plastic on the paralyzed side:
   • Cutting out a flap on the leg of the chewing muscle and fixing it to the paralyzed corner of the mouth (according to PV Naumov);
   • muscle "neurotization" by sewing flaps from the actual chewing muscle with various paralyzed facial muscles;
   • muscular "neurotization", supplemented by pulling the corner of the mouth with a strip from the fascia of the thigh;
   • myoplasty by the method of MV Mukhin;
   • myoplasty and blepharoplasty according to the method of MV Mukhin - B. Ya. Bulatovskaya;
   • one-stage myoexplantodermatoplasty by the method of MV Mukhina-Yu. I. Vernadsky.
2. Transplanting the sublingual nerve into facial muscles.
3. Operations on the facial nerve: decompression, neurolysis (release of the nerve from the scars), free transplantation.
4. Sewing the central segment of the facial nerve with the sublingual, additional or diaphragmatic.

The treatment plan for the third group of operations is based on whether there are deformations of the jaws. Although osseous-plastic surgery is a third group, correction of the lower jaw, if necessary, should be performed first. It should take into account the nature and severity of bone deformation.

If laterognathia is combined with an open bite, two-sided osteotomy should be performed in the form of a resection of wedge-shaped fragments of the body of the lower jaw.

With the isolated (without open bite) laterogenia, linear osteotomy is shown at the base of the usually elongated articular process on the healthy side. Osteotomy is combined with resection of a small bone fragment of the jaw branch. After 2.5-3 months after osteoarthritic surgery, deform soft tissue in the corner of the mouth, cheeks and eyelids. Lastly, they perform operations on the forehead.

Mioexplantodermatoplasty according to MV Mukhin-Yu. I. Vernadsky

With the preservation of the functional ability of the masticatory muscles, the following corrective measures are used: muscle plasty (dynamic suspension according to MV Mukhin) in combination with explantoplasty - static suspension to the malar bone (according to Yu. I. Vernadsky) or kinetic suspension to the coronoid process E. Yagizarov).

Simultaneously, excision of excess skin and subcutaneous tissue in the temporal and parotid regions, as well as in the nasolabial groove (dermatoplasty Yu. I. Vernadsky or ME Yagizarov) is performed simultaneously.

Mioexplantodermatoplasty according to MV Mukhin-Yu. I.Vernadsky is a one-stage operation, combines all the above-mentioned corrective components.

The procedure of the operation. In the area of the nasolabial fold of the patient's side, a linear cut of the skin and subcutaneous tissue 3-4 cm long is made. If the tissues of the diseased side of the face are very stretched, two incisions are made, converging at the ends and spaced 1-1.5 cm apart in the middle part. Between the cuts, the skin and subcutaneous tissue are excised, the circular muscle of the mouth in the area of its angle is exposed through the wound.

On the paralyzed halves of the upper and lower lips, the skin is pierced horizontally with the point of the scalpel in 3-4 places; intervals between punctures - 1.5 cm. Through these punctures, the lip is repeatedly pierced horizontally with a polyamide filament (d = 0.5 mm), whose ends are held in the wound in the region of the nasolabial fold. After that, a wound with a thin polyamide thread (d = 0.15 mm) is applied to the wound punctures.

In the parotid, temporal regions and behind the auricle, two cutaneous incisions converge at the ends, as in the usual cosmetic operation of smoothing wrinkles or pulling up the pendulous cheeks. The skin between these incisions is excised. Bare and fully resize the zygomatic arch (according to MV Mukhin's method).

Between the wounds of the nasolabial fold and in the area of the zygomatic arch, a subcutaneous tunnel is created through which the ends of the polyamide filament used for the lip stitching are drawn from the wound at the corner of the mouth to the wound on the temple. Tighten the corner of the mouth at the ends of these threads and, attaching them with a knot, strengthen on the front ledge-cut of the zygomatic arch, to which the burr is punched, so that the thread does not accidentally slip during further manipulation. Thus, the angle of the mouth dropped earlier is adjusted to its normal level by the pupillary and horizontal lines.

Expose the temporal muscle and from it they cut out and flake from the temporal bone two flaps (according to MV Mukhin's method). The anterior lead through the subcutaneous tunnel in the lower eyelid to the lower part of the circular muscle of the eye to the bridge of the nose, and the posterior-lower one through the skin tunnel (reaching the nasolabial fold) to the circular muscle of the mouth. Muscular flaps, respectively, are hemmed with catgut to the fascia of the interbrother space and the circular muscle of the mouth (in the region of its angle). On the cutaneous wound in the zone of the nasolabial fold, temple, auricle, seams are made of polyamide thread with a diameter of 0.15-0.2 mm.

Myoeksplantodermatoplastika provides not only a static, but also a dynamic (functionally-muscular) effect, as the angle of the mouth is not only set in the correct position, but also gets the opportunity to shift due to the active reduction of the transplanted temporal muscle flap.

The corner of the mouth, tightened by a polyamide thread to a normal level, provides the displaced muscle flap with the possibility of engraftment, not in a stretched, but in a relaxed state, without the risk of rupturing weakening catgut sutures every day and mixing the end of the flap up and out.

In addition to the usual bandage, a wide band of adhesive plaster should be fixed (for 3-4 weeks) the angle of the mouth and cheek in a state of hypercorrection (according to the method of Yu. V. Chupryna).

The patient is prescribed a general rest, forbids smoking and talking. Recommend to take only mashed food.

If the operation is performed correctly and the primary tension is healed, the first contractions in the transplanted muscular flaps appear in the period from 4 to 19 days after the operation. The necessary conditions for the operation are a careful detachment of muscle grafts from the temporal bone scales, the creation of sufficiently free subcutaneous tunnels for them, and fixing the ends of the flaps in an unstretched state.

Unfortunately, in the transplanted muscular graft, gradual degenerative changes gradually developed in some degree, revealed in experiments by P. V. Naumov et al. (1989) using electron microscopy. Therefore, it is necessary to stimulate blood circulation and contractile function in the flaps as soon as possible after the operation.

To stimulate the contractility of the transplanted muscle grafts after the removal of the sutures (usually from the 10th day), myogymnastics (arbitrary cuts of the flaps) and electrical stimulation, dibazole, thiamine are prescribed.

Studying in front of a mirror, patients are trained to measure the reduction of transplanted flaps and facial muscles of the healthy side. If necessary, resort to an additional intervention - the intra -oral intersection of the abdomen of the large zygomatic muscle and the muscle of laughter on the healthy side (to balance the intensity of the displacement of the corners of the mouth with a smile).

According to the data of OE Malevich and VM Kulagin (1989), the addition of myogymnia to the procedures of electrostimulation of the transplanted muscle (bipolar transcutaneous technique by sinusoidal modulated currents with the help of the apparatus "Amplipulse-3T") allows to start treatment from 5-7 days after the operation and, simultaneously acting on the mimic muscles of the healthy side and on the operated side, to achieve a higher functional result of treatment.

Myoeksplantodermatoplastika can simultaneously solve three problems: static suspension of the lowered corner of the mouth, transplantation of active muscle grafts, removal of excess (stretched) skin and subcutaneous tissue.

The comparative simplicity of the operation technique makes it possible to recommend it for execution in the conditions of any maxillofacial department.

In cases where the paralysis extends only to a group of facial muscles woven into the corner of the mouth, and the frontal muscles and the circular muscle of the eye are not paralyzed, it is possible to cut out the muscle flap not from the temporal muscle but from the actual chewing muscle according to PV Naumov's technique or resect (by the method of Burian) coronoid process of the branch of the lower jaw and fix to it a polyamide thread, which pulls the angle of the mouth outward and upward.

Myoplastic surgery according to MV Mukhin-ME Yagizarov

It differs from the above that soft tissues are suspended not to the zygomatic arch, but to the coronoid process of the lower jaw. The operation begins with the scraping of the muscle flap and resection of the zygomatic arch according to MV Mukhin. Then the cutaneous flap is cut in the area of the nasolabial fold according to ME Yagizarov. Between the two wounds a subcutaneous tunnel is created, through which four lavsan threads are passed from front to back and upwards, the lower ends of these threads are fixed to the tissues of the corner of the mouth, and the upper ends are wound around the coronoid process. After tying the nodes of the threads through the subcutaneous tunnel, a muscle flap is carried from the top to the bottom and forward, the end of which is sewn to the circular muscle of the mouth.

Carrying out myoplasty according to MV Mukhin, it is possible, at the suggestion of B. Ya. Bulatovskaya, to split the anterior-front flap, cut from the anterior part of the temporal muscle, into two parts, one of which is injected into the subcutaneous tunnel in the upper eyelid, in the tunnel in the lower eyelid. Both these parts of the muscle flap lead to the inner corner of the eye and there they are stitched together. At the same time, allo or xenochrass (preserved by deep cooling or fixed in alcohol) is used to weight the upper eyelid, which is injected in the form of thin plates or crushed through a revolver syringe into the soft tissues of the upper eyelid below the muscular flap, closer to the inner corner of the eye. With regard to the westernization of soft tissues at the site of the collection of muscle flaps in the temporal region, it is eliminated at the end of the operation by chondro- or osteoplasty.

Insulated mouth angle suspension

If paralysis of the mimic muscles is accompanied by paralysis of the trigeminal nerve (with atrophy of the masticatory muscles) or if the elderly age and the general condition of the patient do not allow the myoplastic component of the operation to be performed, we can confine ourselves to static suspending and dermatoplasty using the method of Yu. I. Vernadsky (see above) or kinetic suspension and dermatoplasty according to ME Yagizarov.

Isolated Kinetic Suspension has the following advantages:

• mobility in the corner of the mouth is achieved)
• the distance between the two attachment points of the thread (angle of mouth - coronal process) does not change, which avoids overloading of the suspending thread and rapid eruption of the tissues in the corner of the mouth; c) access to the coronoid process occurs through one wound.

From this wound, the tunnel is bluntly laid to the coronoid process and the Deshana ligature needle is carried from the inside outwards (through incisura mandibulae), and then thick (No. 3) lavsan filament folded in half. To the ends of the thread hang the tissues of the corner of the mouth, both lips, septum of the nose and chin, which allows you to evenly pull up the displaced parts of the face.

It should be noted that it is advisable to combine both isolated static and kinetic suspension with myotomy (myorezectomy) on the healthy side (often zygomatic and muscular muscles). Due to this, rapid eruption of plastic threads is prevented and a closer symmetry of the half of the face at rest and during a smile is achieved.

The advantage of an isolated static stitching by polyamide threads according to the method of Yu. I. Vernadsky is that it can be carried out even through a relatively small incision in the region of the nasolabial fold, which minimizes the traumatism of the patient.

The paralytic (isolated) lagophthalmus should be better not removed by transplanting the muscle flap from the temporal muscle, but by scleroblerefaroraphy according to ME Yagizarov, by sewing the lower eyelid with the introduction of a plastic implant or by creating a "shell" of the lower eyelid by the method of Grignon, Chowerd, Benoist modified by ME Yagizarov.

Scleroblerefarorrhaphy

Scleroblerefarorrafia, or fixation of the lower eyelid to the sclera, is based on the use of the peculiarities of the Bell phenomenon described above, in particular, the movement of the eyeball upward when closing the eyes. The lower eyelid fixed to the eyeball moves at the same time with it and therefore densely closes with the upper eyelid, and when it opens the eyes it drops.

Scleroblerefarorrafia according to M.Y. Yagizarov is shown only for the first version of the Bell phenomenon.

Operation technique. In the middle third of the lower eyelid and sclera, symmetrical sickle-like wound surfaces are created by excision of the lunate graft of the conjunctiva (slightly longer than the corneal diameter) in the region of the limb below the cornea with the outcrop of the sclera).

Accordingly, the conjunctiva of the lower eyelid is also excised to create a wound surface as close as possible to the edge of the eyelid. Apply three episcleral catgut suture (№00 or №000). The ends of the sutures carried through the epicler are led out through the wound surface of the lower eyelid.

The edges of the wound defect of the conjunctiva on the sclera are stitched with the edges of the defect in the lower eyelid. Episcleral sutures on the skin of the eyelid can be immersed through small incisions on the skin. After the operation, a light, pressing binocular bandage is applied.

In the postoperative period for the immobilization of the eyeball, canned glasses with one transparent area in the center of the glass for a healthy eye, and the operated eye for 7-10 days is under the bandage.

Suspension of the lower eyelid with the introduction of the "shell" (in the modification of M. E. Yagizarov)

In the thickness of the century, a sickle-shaped plastic implant is introduced. This implant is prepared before the operation using a previously modeled and carefully pre-filled wax template. The highest part of the implant is its internal pole, which allows to narrow the area of the lacrimal lake.

The implant is suspended with some hypercorrection by thin lavsan filaments to the periosteum of the outer margin of the orbit and to the medial adhesion of the eyelids. As a result, it is possible, in the first place. Raise the lower lid evenly throughout its entire length, which distinguishes this method from other methods of suspension by strings and strips. Secondly, the implant inserted into the thinned eyelid improves its cosmetic appearance and creates a tight fit to the eyeball.

Correction of the eyebrow and the superciliary region according to ME Yagizarov

The operation is performed by sewing with thick lavsan thread (№2-3) subcutaneous tissue in the eyebrow area and pulling it up with separate threads (№3-4) to the aponeurosis and periosteum in the scalp area. When carrying the thread, the skin areas corresponding to the forehead furrows (wrinkles) are more superficially captured. This creates a symmetry of the supraorbital area.

If it is necessary to uniformly tighten the whole eyebrow (and not only its individual areas), it is recommended to fix a thin, dense plastic explant bent in the eyebrow shape in the thickness of the eyebrow. Individual threads pull the implant to the aponeurosis.

Of great practical interest are experimental and clinical studies by EG Krivolutskaya and co-workers. (1991), aimed at restoring some damaged branches of the facial nerve with its preserved trunk; when the tumors of the parotid gland were removed, the authors resected portions of the branches of the facial nerve that had an intimate connection with the tumor envelope. Using the technique of sewing the distal end of a damaged branch in the "end-to-side" type to an intact branch of the same nerve, the authors achieved complete success in 70% of patients, partial - in 20%.

Of great interest is the report of Ts. M. Shurgai, AI Nerobeev and co-authors. (1991, 1995) on indications and techniques for cross-facial transplantation and muscle neurovascularization (in 15 patients). The authors prefer the gastrocnemius nerve as a transplant and believe that a cross-facial transplantation of the facial nerve should be performed in all cases of irreversible paralysis, and in cases of absence of any functional movements after such an operation, carry out a free transfer of the neurovascularized muscle to replace atrophied facial muscles. It should be agreed with them that such a technique for treating facial paralysis is promising, but requires further improvement.