Bell ’s palsy

Definition(Bell’s palsy): Lower motor type of neuron lesion of facial nerve,the site of damage is probably the labyrinthin portion of the facial nerve with in the facial canal.

Or,

Bell's palsy is a weakness (paralysis) that affects the muscles of the face. It is due to a problem with the facial nerve. The weakness usually affects one side of the face. Rarely, both sides are affected. Many people who have a Bell's palsy at first think that they have had a stroke. This is not so. Bell's palsy is very different to a stroke and full recovery occurs in most cases. Bell's palsy is named after the doctor who first described it.

What is the facial nerve?

You have a facial nerve (also called the seventh cranial nerve) on each side of your face. Each facial nerve comes out from your brain, through a small tunnel in your skull just under your ear.

The nerve splits into many branches that supply the small muscles of the face that you use to smile, frown, etc. It also supplies the muscles that you use to close your eyelids.

Branches of the facial nerve also take taste sensations from your tongue to your brain.

What Causes Bell’s Palsy?

Although Bell’s palsy affects the seventh cranial nerve, experts are not sure why this happens. Many think that a viral infection is the most likely cause of the condition.

The following conditions might play a role in the development of Bell’s palsy:

• herpes simplex, which causes cold sores and genital herpes

• HIV

• middle ear infection

• Lyme disease

• sarcoidosis

• herpes zoster virus, which causes chickenpox and shingles

• Epstein-Barr virus, which causes mononucleosis

• cytomegalovirus

Major affecting muscle:

a) Occipitofrontalis:Rise eyebrow.

b) Orbicularis oculi:Close eye.

c) Corrugator:Deaws eye brow together.

d) Orbicularis oris:Close the mouth.

Other signs and symptoms of Bell’s palsy include:

• drooling

• difficulty eating and drinking

• inability to make facial expressions such as smiling or frowning

• facial weakness

• muscle twitches in the face

• dry eye and mouth

• headache

• sensitivity to sound

If you develop any of the symptoms of Bell’s palsy, seek medical attention immediately. Never self-diagnose Bell’s palsy, as the symptoms can mimic other conditions such as stroke, Lyme disease, and cranial tumor.

Diagnosis:

Examination for Bell palsy includes the following:

• Otologic examination: Pneumatic otoscopy and tuning fork examination, particularly if evidence of acute or chronic otitis media

• Ocular examination: Patient often unable to completely close eye on affected side

• Oral examination: Taste and salivation often affected

• Neurologic examination: All cranial nerves, sensory and motor testing, cerebellar testing

Grading:

The grading system developed by House and Brackmann categorizes Bell palsy on a scale of I to VI,[3, 4, 5] as follows:

Grade I: normal facial function

Grade II: mild dysfunction

Grade III: moderate dysfunction

Grade IV: moderately severe dysfunction

Grade V: severe dysfunction

Grade VI: total paralysis

Testing:

Although there are no specific diagnostic tests for Bell palsy, the following may be useful for identifying or excluding other disorders:

• Rapid plasma reagin and/or venereal disease research laboratory test or fluorescent treponemal antibody absorption test

• HIV screening by enzyme-linked immunosorbent assay and/or Western blot

• Complete blood count

• Erythrocyte sedimentation rate

• Thyroid function

• Serum glucose

• CSF analysis

• Blood glucose

• Hemoglobin A1c

• Antineutrophil cytoplasmic antibody levels

• Salivary flow

• Schirmer blotting test

• Nerve excitability test

• Computed tomography

• Magnetic resonance imaging

Treatment

In most cases, Bell’s palsy symptoms improve without treatment. However, it can take several weeks or months for the muscles in your face to regain their normal strength following an episode of Bell’s palsy.

The following treatments may aid in your recovery.

Medication

• corticosteroid drugs, which reduce inflammation

• antiviral medication, if a virus is the cause

• over-the-counter pain medication such as ibuprofen or acetaminophen for mild pain

Home Treatment

• using eye drops and an eye patch (for dry eye)

• placing a warm, moist towel over your face to relieve pain,

• massaging your face

• doing physical therapy exercises to stimulate your facial muscles

If the facial weakness does not recover:

For the small number of cases where the facial weakness does not recover fully, and remains unsightly, some techniques may be considered. For example:

• Physiotherapy; a treatment called, 'facial retraining' with facial exercises may help.

• Injections of botulism toxin (Botox®) may help if spasm develops in the facial muscles.

• Various surgical techniques can help with the cosmetic appearance.

Long-Term Complications of Bell’s Palsy

Complications of Bell’s palsy include:

• excessive drying of the eye, which can lead to the development of eye infections, ulcers, or even blindness

• untreatable damage to the cranial nerve

• synkinesis, a condition in which moving one body part causes another to move involuntarily. For example, when you smile, your eye may close.

Prognosis:

a) 50-80% get full recovery with in 3 weeks with or without treatment.

b) Recovery occurs with in 2 weeks to 6 month.

c) Nerve regenerate 1 mm per day.

d) Delayed recovery causes complication.

Physiotherapy management: (No reference)

[A]During paralysis:

a) Stroking(Rubbing) in an upwards and downwards.

b) Slow finger kneading over paralyzes muscle.

c) Quick stretching.

d) Strengthening weak facial muscle.

e) Mime therapy (using mirror).

f) Brush and floss.

g) UST,IFT,Galvanism.

h) Relaxation.

i) Biofeed back trainig.

j) Accupuncture.

k) Eye care.

l) Recoordination exercise of facial muscle.

[B]Recovery stage:

a) Quick stretch technique.

b) Protection of the eye with wet cotton wool.

[C]Exercise:

a) Look surprised then frown.

b) Squeeze eyes,closed then open wide.

c) Smile,grin,say ‘O’.

d) Say a,e,i,o,u