Facial paralysis can be an emotionally and psychologically devastating problem. There are numerous causes, with the final common pathway being either partial or total loss of facial movement on the affected side of the face. Sometimes nerve repairs are performed with in the first weeks to months of injury or at the time of paralysis if there has been an obvious transection of the nerve from trauma or tumor resection with a primary end to end repair or cable graft, which involves placing another, different nerve between the two residual ends. This commonly results in some degree of synkinesis, or dysfunctional muscle movement with good muscle tone at rest and is the best option to attempt to restore natural facial movements. If the proximal end of the facial nerve is not available for repair then a cross facial nerve graft or hypoglossal jump graft or direct repair may be used. The cross facial nerve graft involves using a branch of the opposite healthy facial nerve and a nerve graft that is tunneled to the damaged side to provide input to the damaged facial nerve and paralyzed muscles. With a hypoglossal procedure, the nerve that provides movement to the tongue is used to innervate the damaged facial nerve. The hypoglossal procedures require significant physical therapy for good outcomes and can be a good option in experienced hands.
If there is no option for one of the direct repairs or nerve graft procedures then facial reanimation is best achieved by restoring eye function and facial tightening and lifting procedures. When the eye is unable to close there can be chronic irritation due to dryness despite the use of lubricants and taping of the eyelid at night. The irritation can progress to corneal ulcerations and permanent vision problems if not addressed in a timely manner and should be co-managed with an Ophthalmologist to help make the decision for the timing of a definitive repair. With the loss of neural input, the upper eyelid does not close completely and the lower eyelid will droop with resultant chronic tearing and irritation. The procedure to restore eye function often includes placing a gold or platinum weight in the upper eyelid to assist with closure and tightening the lower eyelid to reduce tearing and allow for complete eye closure. Less commonly, some physicians may use a spring to assist with eye closure. Once eyelid function is restored the other facial asymmetries should be addressed either at the same procedure or with a separate surgery.
The general rule of thumb with the timing of facial reanimation is to wait 12 months before intervention to allow for return of function following the paralysis. The corner of the mouth and smile are often affected significantly with facial paralysis patients and can be addressed in several ways. Restoring symmetry of the mouth at rest is of primary importance. This can be accomplished with both static and dynamic reanimation procedures. The two most common static procedures include gortex suspension slings and fascia lata grafts. The facia lata graft is taken from the leg and each are used to pull the corner of the mouth up, but there is no ability for movement following the procedure. Dynamic reanimation procedures are intended to restore symmetry and movement of the lip following the procedure and they include: a temporalis muscle sling, a gracilis free graft, and a temporalis tendon transfer. The temporalis muscle sling uses one of the muscles involved in chewing, with a portion brought down and connected to the corner of the mouth. Because it uses healthy muscle, movement of the corner of the mouth is possible with smiling. The downside to this procedure is fullness and bulkiness over the cheek due to the extra tissue brought over the cheek bone. The gracilis free graft uses a muscle from the leg that is hooked up to the opposite facial nerve to allow contraction and movement of the corner of the mouth. Most recently, the temporalis tendon transfer has been used to restore symmetry and movement and involves repositioning the temporalis muscle tendon from the jaw to the corner of the mouth alleviating the bulkiness of the temporalis muscle sling.
Unfortunately there is no procedure to restore movement to the brow and consequently making the brow heights symmetric is the primary goal. This involves a brow lift procedure on the affected side to correct the asymmetry. Additionally, Botox may be used on the opposite, normal side to reduce movement and the ability of others to recognize differences with facial expressions. A facelift and midface lift may also be used to elevate the cheek and correct the jowls on the affected side, further improving facial symmetry. If significant problems with drooling and difficulty controlling secretions and food exist, the lower lip may be tightened by removing a portion of the lip and tightening the lip muscle.
Facial paralysis is a complex problem with many different ways to address the issues and no single best procedure. Often the management requires the expertise of a neurotologist and a facial plastic surgeon for optimal results. The type of procedure selected for corrective facial paralysis surgery requires knowledge about the options available and the indications for their use. Consultation with a skilled facial plastic surgeon is important to achieve the best results and avoid disappointing outcomes.
