We provide a range of Bell’s Palsy consultation services in Woodbury & Eagan. Bell’s Palsy is a form of facial paralysis resulting from a dysfunction of the cranial nerve VII (the facial nerve) causing an inability to control facial muscles on the affected side. Several conditions can cause facial paralysis, such as a brain tumor, stroke, and Lyme disease. However, if no specific cause can be identified, the condition is known as Bell’s palsy. Named after Scottish anatomist Charles Bell, who first described it, Bell’s palsy is the most common cause of acute facial nerve paralysis.
The facial nerve controls a number of functions, such as blinking and closing the eyes, smiling, frowning, lacrimation (tear production), salivation, flaring the nostrils and raising the eyebrows. The facial nerve also carries taste sensations from the anterior two-thirds of the tongue, and helps the ear to dampen very loud sounds. Because of this, patients with Bell’s palsy may hear sounds more loudly or notice a decreased or unusual sense of taste.
What causes Bell’s palsy?
The cause of Bell’s palsy is still not known. There is some evidence that it could be caused by a herpes simplex virus 1 (HSV-1) infection of the facial nerve. The body can clear the infection but not before the facial nerve swells. The nerve swells so much that it loses blood supply, stopping the transmission of nerve impulses. Based on this understanding, the treatment for Bell’s palsy is steroids (prednisone) to decrease nerve swelling, and sometimes anti-viral medication (for example acyclovir or Valtrex) to clear the viral infection more quickly.
Bell’s palsy is a diagnosis of exclusion. What this means is that facial weakness or paralysis is attributed to Bell’s palsy ONLY after all other possible causes are considered and eliminated. Bell’s palsy is sudden in onset and usually progresses from normal facial movement to peak facial weakness over 72 hours or less. It is not uncommon to notice some discomfort around the ear. Most patients will begin noticing return of facial movement within a few weeks. Even without any treatment, about 85% of patients with Bell’s palsy will return to normal or very near normal facial function. Bell’s palsy never causes permanent complete facial paralysis. If a patient has noticed no return of facial movement after 6 months, it is not Bell’s palsy. At that point, a different diagnosis must be sought.
One disease that is very similar to Bell’s palsy is shingles of the face, also called Ramsay-Hunt syndrome. The major differences in this condition are small blisters on the external ear and/or hearing loss, but these findings are not always present (called zoster sine herpete). Ramsay-Hunt syndrome, like all shingles, is caused by reactivation of the Herpes Zoster virus. People with Ramsay-Hunt syndrome are more likely to have persistent facial weakness or synkinesis than patients with Bell’s palsy.
What is synkinesis?
The facial nerve starts out as one large branch as it emerges from the base of the brain (like a tree trunk) but divides into 5 main and then multiple smaller branches as it enters the face (see image below). In Bell’s palsy, the nerve seems to be damaged at the base of the skull where it is passing through a very small canal in the bone. When the nerve recovers, the nerve fibers (called axons) don’t know which of the 5 main branches they are supposed to go to. In other words, the axon that is supposed to go from the brain to the muscle that closes the eye might accidentally go to the muscle that creates a smile. So, when the patient tries to blink, the corner of the mouth may move. This is called synkinesis, or unintended or uncontrolled facial movement. Approximately 85% of people with Bell’s palsy make a complete recovery, but the other 15% of people develop moderate to severe synkinesis. Ironically, the most common negative result of Bell’s palsy is too much and/or uncontrolled facial movement.
How do you treat synkinesis?
People with synkinesis are usually bothered by 3 things:
- Unintended facial movement: the most common example of this is the eye closing during smile.
- Facial tightness: the muscles particularly of the cheek can be in a constant state of partial activity, which creates tightness and chronic facial discomfort. Sometimes this facial tightness prevents a person from creating a smile on one side, called a “frozen smile.”
- Facial asymmetry: the symmetry of the face can change, even at rest.
There are treatments for all 3 of these symptoms. The 2 main treatments for synkinesis are physical therapy and botulinum toxin injections. The purpose of physical therapy is to teach the patient techniques to help relax the face and gain better control over facial movement. Botulinum toxin injections weaken muscles that are too tight. Botox and Dsyport are brands of botulinum toxin.
You can use Botox injections to partially weaken the muscle that closes the eye so that it doesn’t close so tight during smiling. Botox can also be used to weaken the muscles that pull down on the lip, which can release a “frozen smile” and allow a patient to create a more symmetric and pleasing smile. For patients who develop significant facial asymmetry at rest, temporary injectable fillers like Juvederm, Sculptra, Belotero or Restylane can be used to create better facial symmetry.
Above at right is a patient who developed rather severe right facial synkinesis after Bell’s palsy. As you can see in the before picture, she has a smaller eye, with cheek tightness, a band of muscle in the neck, and wrinkling of the chin on her right side. In the after picture, you can see that her face looks much more relaxed and symmetric.
Schedule a consultation with our staff to find out if it is right for you.