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Diagnosis and Treatment of Facial Paralysis
Thomas M. Jung, M.D. Ph.D.
Neurotologist for Tri-State Otoloaryngology
Ralph Waldo Emeron said, “A man finds room in few square inches of the face for traits of all his ancestors; for the expression of all history, and his wants.” It is that part of ourselves that we present to the world. For better or worse, people often form their first impressions of us by our apperence. Therefore, a facial nerve paralysis can be particularly devastating. Often the first symptom of a facial nerve paralysis can be a heavy feeling on one side of the face. This is followed by an inability to smile or blink on the paralyzed side. Often people will say that they have twitching on the opposite side. This is due to the fact that the paralyzed side cannot move and attempts to move the face only move the opposite side.
It is the facial nerve that connects the brain to the muscles of facial expression, and an injury to this nerve can result in a facial paralysis. The most common cause of a facial paralysis (57%) is due to a viral infection of the nerve. Recent studies have demonstrated that the Herpes Simplex Virus is the cause of this type of paralysis. When one side of the enire face becomes paralyzed or weak over the course of 24 hours, it is called Bell's Palsy. This type of weakness is usually treated with steroids and anti-viral medications. The reason why the facial nerve is so affected is because it has the longest course of any nerve through the bone. When a nerve becomes infected it tends to swell. However, if the nerve is traveling through bone, the swelling tends to compress the nerve and prevent it from allowing signals to travel along its length, leading to paralysis. If the affected side of the face still has some movement, that means some signals are getting through. Those patients with Bell's Palsy and some movement will have an excellent recovery – however, 10% may have a poor outcome. These are the patients that may benifit ftom decompressing the facial nerve from its bony course. It is important to decompress the nerve in its entirety before permanent damage occurs. Studies have shown that if you merely decompress the nerve as it travels through the middle ear, you will not decompress the narrowest portion. Facial nerve decompression needs to be performed through a middle fossa approach which is performed by a neurologists or neurosurgeon.
The remainder of causes of facial nerve paralysis include trauma, such as a base of skull fracture or a laceration, middle ear infections or tumors. Although strokes are often thought to result in facial weakness, it is extremely rare for strokes to cause an isolated facial nerve weakness without any other symptoms. When a facial nerve is injured by trauma, often it can be repaired by various techniques which include grafting the nerve to itself or splicing it to another nerve of the face. The appropriate technique depends of the type of injury. Needless to say, gunshot injuries to the face often result in more extensive injuries because the nerve is actually heated and burned by the bullet.
It is important however, never to let a facial nerve paralysis go untreated. Early intervention improves outcome. In addition, one needs to always be wary of tumors that can cause facial nerve paralysis. When paralysis is due to a tumor, the paralysis often progresses slowly and often is associated with twitching and facial spasm. If a tumor is discovered, the affected portion of the nerve can be removed and grafting can be performed to reconnect the nerve to the muscles of the face. Again, the earlier the intervention, the less the atrophy of the muscles and better the outcome. Early intervention and a correct treatment program allow you to always put your best “face” forward.
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