What causes facial palsy?
Facial palsy can be caused by a number of different things some of which are listed here:
- Viral infection is a common cause of a facial palsy known as Bells Palsy.
- The Herpes Zoster virus can cause a more aggressive form of facial palsy known as Ramsay Hunt Syndrome. This is the same virus which causes Chicken Pox and Shingles (not cold sores).
- Surgery to remove a facial nerve or acoustic nerve tumour can cause facial palsy. The acoustic nerve lies very close to the facial nerve so in the process of removing these tumours the facial nerve can become damaged.
- Surgery to the parotid gland. The facial nerve runs through this salivary gland and so can be damaged during surgery.
- Bacterial causes (e.g. Lyme Disease or following a middle ear infection).
- Neurological conditions (e.g.Guillain-Barre syndrome or Neurofibromatosis).
- Traumatic injury such as brain injury, skull or face, as might be suffered in an accident.
- Congenital condition, which means an abnormality of the facial nerve you are born with.
- Stroke can cause facial palsy as a result of damage in the brain but this is slightly different to the causes above, which directly affect the nerve after it leaves the brain.
The incidence of Bells palsy (one type of facial palsy) is believed to be approximately 1 in 5000 with the incidence of all facial palsies closer to 1 in 3000. (30 cases per 100,000 per year) Approximately 50% of Bells palsy patients will have essentially complete recoveries in a short time. Another 35% will have good recoveries in less than a year.