- What is facial palsy?
What is the facial nerve?
The nerve affected in facial palsy, the facial nerve, is one of the cranial nerves. It is also called the seventh cranial nerve. It has a complex course from the brain stem to reach the muscles of facial expression. It supplies and controls the muscles that lift the eyebrows high, the muscles that close the eyelids, the muscles of the cheek and around the mouth.
What are the causes of facial palsy?
Facial palsy can be congenital i.e. present at birth or shortly after, or can be acquired. Acquired causes of facial palsy include most commonly Bell's palsy. This can have no cause or be secondary to infection, or can be because of lack of the blood supply to the nerve. Sometimes a tumour, such as an acoustic neuroma, or parotid gland, or temporal bone tumour can compress the nerve and damage it. Birth trauma or skull fracture can also cause a facial palsy.
- What are the symptoms of facial palsy?
Facial paralysis usually affects one half of the face. There is a flattening of the affected half of the face, with loss of the forehead wrinkles and horizontal lines, a droopy eyebrow, difficulty closing the eye, an inability to whistle and the corner of the mouth pulled down.
- Why are the eye changes so important?
The eye findings are particularly important, as the upper eyelid can be a little bit too high and the lower eyelid can sag and have an ectropion (outward turning of the lid margin) resulting in a watering eye, inability to close the eye and exposure or drying of the cornea. The eye can become red, the vision blurred and occasionally the vision can be severely affected by an exposure keratopathy, with an ulcer then scarring of the cornea and loss of useful vision.
- How is facial palsy managed?
Most patients can be managed medically, with local eye drops and ointment to lubricate and wet the eye. There are many artificial tear preparations available. Simple horizontal taping of the eyelids at bedtime is very beneficial. Some patients require upper eyelid lowering with Botox (Botulinum Toxin A), which specifically paralyses the eyelid muscle which opens the eye, and allow the eyelid to drop over the surface of the eye and protect it if there is a severe keratopathy present.
- When is a surgery required?
Surgery may be advised for facial nerve palsy if there is difficulty in protecting the eye from incomplete closure of the eye causing drying and there is a lot of discomfort and/or effect to the eyesight. Surgery is also done to improve symmetry and regain the normal anatomy, in order to improve not only cosmesis, but help improve the function of the eyelids and reduce watering. Surgery is also done on the forehead, brow, midface and lower face and corner of the mouth to improve symmetry.
- Common surgical procedures for facial palsy
Lateral tarsorrhaphy
this is the surgical closure of the outer portion of the eyelids to reduce the length of the eyelids that is open and decrease the evaporation and improve the coverage of the eye by the eyelids. This is usually done in an emergency. It is not the best rehabilitative procedure and it has a poor cosmetic result, can cause a blinkering effect to the vision towards the side of the surgery, and is therefore reserved for special cases only. The lateral tarsal strip is preferred.
Lateral tarsal strip
this is a tightening of the lower eyelid when there is lower eyelid laxity, sagging and ectropion. The lower eyelid is shortened and re-attached a little higher to improve eyelid closure and comfort. An augmented strip - tarsorrhaphy is often needed for facial palsy to help close the eyelid fully on blinking.
Lateral tarsal strip tarsorrhaphy
a combined procedure called an augmented lateral tarsal strip tarsorrhaphy can be done when there is a lot of lower eyelid laxity, sagging and ectropion, and in this surgery there is a long lateral tarsal strip performed with a very small lateral tarsorrhaphy combined, which does not shorten the lower eyelid opening so much as to affect vision or appearance, but does help protect the eye well.
Medial canthoplasty
this surgery is done at the medial corner of the eyelids (in a corner) and consists of some specially positioned stitches to pull up the sagging lower eyelid towards the inner corner. It is usually done in conjunction with a lateral tarsal strip, or augmented lateral tarsal strip tarsorrhaphy.
Gold weight upper eyelid
more animated and better closure of the upper eyelid can be obtained by placement of a gold weight in the upper eyelid.
Drooping eyebrow surgery
this is called brow ptosis correction and there are several different procedures to improve the position of the drooping eyebrow. Some of these procedures are done over the eyebrow, whilst others are carried out via the forehead or small scalp incisions. Brow ptosis can be necessary as part of the rehabilitation in a patient with longstanding facial palsy.
Face surgery
The midface or cheek can be lifted to help improve the lower lid position and more extensive facelift type surgery done to improve the symmetry between the two sides of the face and help restore the normal anatomy. Incisions in front of the ear and into the hairline are used. A sling of the patients own leg fascia (fascia lata) or an inert strip of material can be used to help resuspend the mouth.
- Non-surgical procedures
Botulinum Toxin A chemodenervation upper eyelid lowering: in certain urgent situations the front of the eye, or cornea, becomes ulcerated and very painful, or the eye red. This is called exposure keratopathy with severe keratitis. Lubricants and other eye drops may not be adequate to improve this and it is necessary to lower the upper eyelid temporarily.
This is done by a small injection underneath the upper eyelid of Botox, or Botulinum Toxin A, to temporarily paralyse the muscle that lifts the eyelid open and allow the eyelid to drop over the eye (protective ptosis) so that the keratitis or ulcer can heal. These injections can last up to three months and be repeated, or definitive surgery done.- What are the symptoms of facial palsy?
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