Definition of Facial paralysis - Facial Palsy
Facial Paralysis is a condition where the facial muscles are paralyzed. This occurs when the nerve controlling the facial muscles (nerve facialis) - or the part of the brain that controls this nerve is not functioning properly. We have two facial nerves and generally only one of the two is affected resulting in paralysis of the muscles on one side of the face only. The most common form of facial paralysis is Bells Palsy where the cause of condition is not known but usually the condition is temporary.
Causes of Facial Paralysis or Facial Palsy
Facial Paralysis is most often due to Bell’s Palsy. However, the condition might also arise from:
Infection with herpes simplex or herpes zoster (shingles) virus, chickenpox (varicella zoster) or encephalitis in the form of borrelia often transmitted by the bite of Ticks. In rare cases facial paralysis is a complication arising from middle-ear infection.
- Stroke – i.e. blood clot or bleeding in the brain
- Nerve inflammation, for example Guillain-Barré syndrome
- Fractured skull – the underside of the cranium
- Brain Tumor or tumor in the major salivary gland
- Surgical damage to the nerve facial nerve – or compression from a tumor
Symptoms of facial paralysis
Facial paralysis/palsy usually develops abruptly. The face looks asymmetrical when only one side is paralyzed. The eyelid and the corresponding corner of the mouth drop and there might be ear pain on the same side as well.
Sensory ability is usually normal but the following abilities might be adversely affected or obstructed:
- Inflatation of cheeks.
- Pointed lips (as if you should kiss).
- Wrinkle the brow or close the eye.
- Prior to incident there may have been discomfort or pain around the ear and impaired hearing and reduced sense of taste connected with the anterior 2/3 of the tongue.
If none of the above movements can be performed the paralysis stems from damage to the nerve somewhere in the passage from the brain to the muscles and the condition is called peripheral facialisparese. If the cause of facial paralysis is damage to the nerve cells at the nerve root level it is called central facialisparese. It will then be possible to frown and possible to squint at the paralyzed side, since the part of the facial nerve, which runs to the upper facial muscles are controlled from two different neurons in the brain. The other parts of the face will be paralyzed as with peripheral facialisparese.
If half the face is paralyzed medical attention is required. The examination will determine the degree of paralysis and if there is suspicion of a central facialisparese a CT or MRI scan of the brain will be performed. If there is suspicion of infection, for example encephalitis, borrelia or herpes virus a lumbar puncture may be performed and blood samples taken for examination.
Treatment of Facial Paralysis
Bells Palsy usually needs no treatment as it recovers spontaneously. It the condition is caused by infection antibiotics targeted at the micro-organism will be prescribed. In case of a tumor surgery might be relevant and sometimes the treatment might be a surgical effort to relieve the affected nerve from suspected compression. In some rarer cases transplant of a healthy nerve particle from the skin might be attempted.
If the eye cannot be closed and there is reduced tear production artificial tear liquid is provided. If this is not enough one option might be to stitch together the outer part of the eyelids (tarsorafi) to keep the eye partially closed.
Prevention of facial paralysis
Most forms of facial paralysis cannot be prevented. However, prevention is possible if the facial paralysis is associated with infection with borrelia (Tick bite) by early treatment with antibiotics while there are still only skin symptoms around the Tick bite named erythemamigrans. Vigilance and quick action is advisable in case of Tick bites.
Complications and outlook
The progression and outlook for facial paralysis depends on the cause. Four out five cases are Bells Palsy where the patient recovers spontaneously within some week or maybe a couple of months. If the condition stems from blood infection often there is full recovery but in some cases there is permanent nerve damage.
A permanent facial paralysis can cause problems.
The person might involuntarily discharge saliva with the mouth hanging and there might be problems eating. The affected eye might tend to dry up and the tear production diminished which might lead to cornea inflammation or scratches in the cornea.
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