World's first medical networking and resource portal

Articles
Category : All
Medical Articles
Feb06
Facial palsy
Facial palsy is condition in which there is lesion of the facial nerve and the resultant paralysis in the muscles that it supplies. So there will be following features on the side of lesion:

Loss of facial expression.
Drooping of the face- Low eyelid, eyebrow and corner of mouth sag.
Closing the eye is difficult.
Eating is difficult because food collects in the side of the cheek and fluid seeps out of the corner of mouth.
Speaking, whistling and drinking are impaired.
Non-verbal communication is lost as the patient cannot register the pleasure, laughter, surprise, interest and worry.
The patient tends to sit with the hand over the side of face.
*
There is difference between an upper motor neuron lesion and lower motor neuron lesion of the facial palsy.

A unilateral UMN lesion usually spares the forehead as it is also innervated from the other side of the brain (part of facial nucleus supplying the upper face principally the frontalis muscle receive the supranuclear fibers from each hemisphere); however an LMN lesion affects all of one side of the face.

An upper motor neuron lesion causes weakness of lower part only of face on the side opposite the lesion. The frontalis muscle is spared; the normal furrowing of the brow is preserved, and the eye closure and blinking are not affected. The earliest sign is simply slowing of one side of the face, for example on baring the teeth or smiling.
Moreover, in upper motor neuron lesion there relative preservation of spontaneous 'emotional' movement (e.g. smiling) compared with voluntary movement.

A unilateral lower motor neuron lesion causes weakness of all the muscles of facial expression on the same side. The face, especially the angle of the mouth, falls, and dribbling occurs from the corner of the mouth. There is weakness of the frontalis and of eye closure since the upper facial muscles are weak. Corneal exposure and ulceration occurs if the eye does not close during sleep. The platysma muscle is also weak.

Causes of facial weakness:

These are as under:
The common cause of facial weakness is a supranuclear lesion (UMN) e.g. cerebral infarction leading to upper motor neuron facial weakness and hemiparesis.
Lesions at four other levels may be recognized by the associated signs.

PONS. The sixth nerve (abducens) nucleus is encircled by the seventh nerve fibers and is therefore involved in the pontine lesions of the nerve, causing lateral rectus palsy.
If there is accompanying damage to the neighboring centre for the lateral gaze (PPRF) and the cortispinal tract, there is the triple combination of:

LMN facial weakness
Failure of conjugate lateral gaze (towards the lesion)
Contra lateral hemi paresis

Causes include pontine tumors (e.g. glioma), demyelination and vascular lesions.
The facial nucleus is affected unilaterally or bilaterally in poliomyelitis and motor neuron disease; the lateral usually causes the bilateral weakness.

CEREBELLOPONTINE ANGLE. The fifth, sixth and eight nerves are affected with the seventh nerve in lesions in the cerebellopontine angle where they are grouped together. Causes are acoustic neuroma, miningoma and secondary neoplasm.

WITHIN THE PETROUS TEMPORAL BONE. The geniculate ganglion (a sensory ganglion for taste) lies at the genu of the facial nerve. Fibers join the facial nerve in the chorda tympani and carry taste from the anterior two third of the tongue. The (motor) nerve to the stapedius muscle leaves the facial nerve distal to the genu.
Lesions of facial nerve within the petrous temporal bone cause:
Loss of taste on the anterior two third of the tongue
Hyperacusis (an unpleasant loud distortion of noise) due to the paralysis of the stapedius muscle
Causes include:
Bell's palsy
Trauma
Infection of middle ear
Herpes zoster (Ramsay hunt syndrome)
Tumors (e.g. glomus tumor)

WITHIN THE FACE. Branches of the facial nerve pierce the parotid gland and supply the muscle of the facial expression. The nerve can be damaged here by parotid gland tumors, mumps (epidemic parotitis), sarcoidosis and trauma. The nerve is also affected in the polyneuritis (e.g. G.B. Syndrome) usually bilaterally.
Weakness of facial muscles also occurs in primary muscle disease and disease of neuromuscular junction. Weakness is usually bilateral. Causes include:
Dystrophia myotonica
Facio-scapulo humeral dystrophy
Myasthenia gravis

Bell's palsy
This is a common acute, isolated facial nerve palsy believed to be due to viral infection (most probably herpes simplex) that causes swelling of the nerve within the petrous temporal bone.

MANAGEMENT:
Spontaneous recovery occurs toward the end of second week. Thereafter, continuing recovery occur. Fifty percent recover within three months. Continuing recovery may take 12 months to become complete. About 15 percent of patients are left with a severe unsightly residual weakness.

Medical:

Steroids (prednisolone 60mg daily reducing to nil over 10 days.)
Acyclovir for viral infection

If there is severe residual paralysis, cosmetic surgery and/or reinnervation (nerve anastomosis of the lingual to the facial) are some times performed after a year has been elapsed.

Physiotherapy:

During the paralysis:

The selection of the suitable physical agent depends upon the experience or the choice of an experienced physiotherapist. Physiotherapist may choose from a number of physical agents available.

Ultrasound is given over the nerve trunk in front of the tragus of ear and in area between mastoid process and mandible. There is no fear of applying ultrasound while doing the treatment of patient with Bell's palsy. The ultrasound is always applied on the side of lesion in front of the tragus of ear & in area between the mastoid process and mandible where the maximum tenderness of the facial nerve is determined by palpation. It is applied in slow circular motion with a starting dosage of 1 watt per square centimeter for 10 minutes. The dosage may be increased on the subsequent sessions if no remarkable improvement is noted. Let me explain that ultrasound waves cannot traverse the bone. That means ultrasound has zero penetration in the bone. Infact, ultrasound waves are reflected away from the bone. So there is no fear in applying the ultrasound on face. (This is only for LMN lesion type)

Low level laser therapy (infrared 808 nanometer wavelength 400 mill watt power for 5 minutes continuous)

Infra-red: Infra red may be applied to warm the muscles and improve the function, but you must ensure that eyes are protected with linens when you are applying infra-red to face. Timing should be for 10 to 20 minutes at a distance usually between 50 and 75 cm.

Ultraviolet Therapy: Formerly ultraviolet was frequently used to give third or fourth degree erythema doses over the facial nerve trunk and in area between mastoid process and mandible (at the point of emergence of facial nerve on face)to combat the infection and inflammation. The type of lamp used for this type of treatment is the Kromayer lamp. The Kromayer lamp is a water cooled mercury vapor lamp which eliminates the danger of infrared burn. It has the advantage that it can be used in contact with the tissue or with suitable applicator it can be used to irradiate a suitable body cavity.

Testing the dosage can be done with Kromayer lamp in contact with the skin, so very small holes are used, e.g. 0.25 square cm. since exposure time need only be very short. It is often useful if the Kromayer lamp has standard dosage time recorded on it for contact and 10 cm. The front of the Kromayer lamp is cleaned with an appropriate solution and when it has had its full 5 minute warming up period the lamp is ready for use. The front of the lamp is held as close as possible to the skin or the target tissue. At least an E4 dosage is given. Treatment could infact be given at a set distance of, say 4 cm.

Microwave diathermy: As far as micro wave diathermy application is concerned, there is strict contra indication for the use of micro wave diathermy for the treatment of face as micro waves can spread randomly and can damage the lens of eye causing the opacity of the lens. So there is no room for the application of micro wave to face.

Short Wave Diathermy: SWD can be safely applied for the treatment of facial palsy at the point of emergence of nerve on the face. The technique used may be monopolar or bi polar. In bipolar technique using the capacitor field method or induction or cable method, the one facial mask electrode is used as an active electrode for applying the rays to face while the second or indifferent electrode used on some distant part of the body (usually cervical or dorsal spinal area) to complete the circuit. In monopolar electrode method only one electrode is used to direct the rays to the target treatment area site and no second electrode is used at all. The treatment time is between 10 and 30 minutes. Shorter sessions are used for mild conditions. Treatment is given on daily basis to produce the required results.

Electrical Stimulation: The only form of electrical current used on face is interrupted direct current (I.D.C.) whether or not there is reaction of degeneration. This is requested only to preserve the bulk of facial muscles and to prevent their atrophy while waiting them to be in function whenever their re innervations arrives in case of axotomesis or reconduction after neurapraxia if the nerve is not damaged completely. There is no room for the use of faradic current use on the face as it could lead to cause secondary contractures of the face. Moreover, most patients find it intolerable on face due to its unnecessary uncomfortable sensory stimulation. The is due to the reason that the faradic current has a frequency of 50 cycles per second, and so produces the tetanic contraction of the muscles that it stimulates. Although for muscle contraction faradic current is surged to produce alternate contraction and relaxation yet the tetanic type of contraction produced by these 50 pulses delivered in just one second, is not required on face. The face muscles are very thin and delicate and could not tolerate this tetanic type of contraction and may be damaged to produce the secondary contractures. If secondary contractures are produced, all form of electrical stimulation should be abandoned temporarily to avoid further damage to the muscles. The face should be gently stretched and massaged.

Heliotherapy: I have found traditional old lay men to use the convex*lens to focus the sun rays to produce the third or four degree erythema dosages to facial nerve trunk and in area between mandible and mastoid process behind the ear and it frequently give dramatic result with excellent recovery of facial palsy.* The treatment was needed to repeat after one week to repeat the same session of the dosage.* Only three or four sessions of this kind were needed to*do the excellent management of the patient.* Infact, it is one kind of heliotherapy treatment which is available from the natural source of power i.e. the sun.** This is*most common form of physiotherapy medicine that is used by*conventional lay men here in Pakistan with excellent results of the treatment.* Please, note that sun rays are a mixture of infra red rays and ultraviolet rays and visible rays on the electromagnetic spectrum. The thermal effect is produced by the infra red portion of the sun rays while the chemical effect like tanning of skin, effect on photographic film, formation of vita. D is due ultraviolet portion in the sun rays. The visible rays which are near to infra red portion on the electromagnetic spectrum produces effects similar to infra red rays. The visible rays which are near to ultra violet portion on an electromagnetic spectrum produces effects similar to ultraviolet rays. The erythema formation is due to ultraviolet portion of the sun rays. Usually fourth degree erythema dosage is required to produce the required therapeutic results.

Iontophoresis: Zinc, potassium iodide or chloride iontophoresis is given to the affected ear to treat the otitis media if there is infection of the middle ear.

Massage: The patient derives great benefit from the massage. Massage may be taught to the patient.
Stroking in the upward, outward direction. It is given from chin upwards to the temple and from the middle of forehead downwards towards the ear. The technique should be gentle but at the same time stimulating.
Slow finger kneading applied over the paralyzed muscles maintains skin suppleness and muscle elasticity. Small circular finger kneading can be given all over the affected side of the face, care being taken not to stretch the muscles.
Tapotement may be administered in the form of tapping quickly and lightly with the finger tips. It must be done very gently over the forehead and superficial ridges, where only a thin layer of muscle covers the bone.
Frictions are given at the point where the nerve enters the face to soften any inflammatory deposit.
Vibrations performed with the tip of one or two fingers can also be used over nerve trunk at this point or they may be administered by placing the whole flat hand on the affected side of face.
These techniques applied daily for 5 minutes or so help to maintain lymphatic and blood flow and prevent contractures.

During Recovery:

PNF techniques are used for re-education:
Quick stretch can be applied to regain raising of eye brow and the movement of the corner of mouth.
The physiotherapist can produce the movement passively and then ask the patient to hold, and then try to produce the movement.
Icing, brushing, tapping or brisk stroking may be applied along the length of the muscles. e.g. Zygomaticus
Exercises:
Look surprised then frown
Squeeze eyes closed then open wide
Smile, grin, and say 'o'.
Say a, e, i, o, u.
Hold straw in mouth-suck and blow
Whistle

Please, add more suggestions and your own point of view regarding the treatment of facial palsy, mail us - info@bprc.in or visit www.bprc.in


Category (Brain & Nerves)  |   Views (19347)  |  User Rating
Rate It


Browse Archive