Introduction Bell’s palsy is described as facial paralysis or facial weakness. However, it can result from a large number of disorders including tumors, trauma, infections and central nervous system diseases. Bell’s palsy is thought to result from a Herpes Simplex Virus (HSV) infection involving the facial nerve and remains. It will affect about 1 in 60 people during their lifetime. Men and women are equally affected as are the right and left sides of the face. Pregnant women, especially during the third trimester are more prone to develop Bell’s palsy.
The facial nerve, on its path from the brain stem to the face passes through a narrow bony canal in the base of the skull. The viral infection of the nerve is thought to produce inflammation and swelling. The tight bony canal cannot expand to accommodate the enlarged nerve that becomes subjected to increasing amounts of pressure producing the rapid onset of facial weakness and varying degrees of long term damage. I choose this topic because, in the fifth grade I had it. I had it for about a month.
Anatomy. Once the damage has been done within the cranial canal the nerves then have to re grow around the whole side of the face to the various points. Physiology of the system The facial nerve (also called the seventh cranial nerve) on each side of your face. Each facial nerve comes out from your brain, through a small tunnel in your skull just under your ear. The nerve splits into many branches that supply the small muscles of the face that you use to smile, frown, etc. It also supplies the muscles that you use to close your eyelids.
Branches of the facial nerve also take taste sensations from your tongue to your brain. Physiology of the disease or disorder Bell’s palsy affects the seventh cranial nerve, or CN-VII. It causes facial muscles to weaken or become paralyzed. Originating in the brain stem, it passes through the stylomastoid foramen and enters the parotid gland. It divides into its main branches inside the parotid gland. These branches then further divide into 7,000 smaller nerve fibers that reach into the face, the neck, the salivary glands and the outer ear.
The nerve controls the muscles of the neck/forehead, facial expressions, and the perceived sound volume. It also stimulates secretions of the lower jaw, the tear glands and the salivary glands in the front of the mouth. The sensation of taste from two-third of the front portion of the tongue and sensations at the outer ear are transmitted. Bell’s palsy is caused by inflammation within a small, extremely narrow, bony tube called the fallopian canal. An inflammation within it is likely to exert pressure on the nerve, thus compressing it.
Likewise, if the nerve itself becomes inflamed within the canal, it can encounter pressure and therefore compression. In this case, the nerve has not yet exited the skull and divided into its many branches; the result is the impairment of all functions is controlled. Bell’s palsy temporarily prevents the nerve from transmitting signals to the muscles. Interview Q: How are these patients normally treated? A: The treatment of facial paralysis has significant variations depending on the cause, severity, duration and age of patients.
Bell’s palsy, when initially diagnosed, needs to be treated immediately with high-dose steroids and antiviral medications (Valtrex or Famvir). However, it is paramount that the doctor who diagnoses “Bell’s palsy” rules out more serious conditions such as brain tumors, stroke, and head and neck cancer. Eye protection is also A key factor because most patients in early phases of the disease are unable to close their eyes and run a high risk of developing long-term corneal ulceration and blindness.
Patients are encouraged to tape their eyes shut at night, use artificial tears and lubricate their eyes regularly. Patients who present with long-standing facial palsy will require a more graduated treatment algorithm. There are three main treatment arms that we utilize: neuromuscular retraining, botulinum toxin (BOTOX, Dysport), and surgery. These options need to be tailored to each patient depending on various individual factors. Q: What are the key investigations that should be performed on patients prior to surgery?
A: The underlying cause of facial paralysis needs to be uncovered. I’ve seen many patients in my practice THAT had been falsely diagnosed with “Bell’s Palsy” but turned OUT to have other more serious underlying conditions such as acoustic neuroma or parotid tumors. One should do imaging studies to make sure there are no tumor or growths, an electro myopathy (EMG) to evaluate the nerve input and the muscle action. You want to see what’s really going on. You also want to see if there is any underlying tone to the facial muscles which will help us determine the appropriate operation for the patient.
Q: What are some of the key surgical challenges? A: Every surgery is different. We customize the operation depending on the patient’s desires as well as age, cause, DURATION and severity of the paralysis. Most people have similar desires – IMPROVE FUNCTIONAL DEFICITS, create symmetry of their face, restore the smile mechanism and allow good closure of their eyes. In many patients who have fairly good facial movement, we will only be required to symmetrize their face with tendon transfers and facelift procedures.
In other cases where patients have no movement, we will employ advanced surgical procedures using nerve and muscle transfers. There are two key SURGICAL procedures that truly benefit patients WHEN USED APPROPRIATELY: 1) hypoglossal-facial nerve transfer; 2) cross-facial nerve grafting with gracilis free muscle graft. If patients are candidates for these operations, they have the best opportunity to obtain tone and spontaneous smile mechanism. Q: Are there special considerations when it comes to transplanting nerves versus muscle when working on the face?
A: Nerve and muscle transfers from other parts of the body to the face is now a common procedure for restoring a spontaneous smile mechanism. Or muscle performsural stage. Q: What are the details of those stages? A: In the first stage, we harvest sural nerve from the ankle area and connect it to the normal facial nerve on the unaffected side. We allow the nerve to get necrotized or activated for 6 to 12 months. In the second stage, FREE MUSCLE GRAFT IS UTILIZED. THE gracilis muscle with its nerve, artery and vein is harvested and anchored to the paralyzed side.
The sural nerve is connected to the gracilis nerve (obturator nerve) and the artery and veins are hooked up to facial artery and veins to allow blood supply to the muscle. When the patient smiles on the normal side, the gracilis muscle on the paralyzed side will get activated and move thereby restoring the patience smile. Q: That’s an interesting ‘work-around’. Are there others? A: Many patients require just modified/customized facelift to SYMMETRIZE the face and create more balance to the overall structure.
We often combine this with blepharoplasty and brow lifts to further improve symmetry. Medscape: It sounds like there is a certain amount of puzzle-solving when planning the surgery. Q: Are there differences in how you deal with young versus old patients? A: Absolutely! Younger patients are better candidates for advanced surgical options such as cross facial nerve grafting with gracilis free flap. They have a higher success rate with these operations and have a better nerve regeneration ability. Q: Is there extra training out there for plastic surgeons who wish to do these repairs?
A: I am a co-director of an American Academy of Facial Plastic & Reconstructive Surgery fellowship program and there are two to three other programs in the US that have in-depth training for facial plastic surgeons and plastic surgeons in this arena.
My doors are always open for residents and visitors as well. Surgeons can also get more information from the Facial Paralysis Institute in Beverly Hills, California. Careers * Complementary therapies * Doctor * Law * Literature & Language.
Bibliography * http://www. hopkinsmedicine. org * http://www. ninds. nih. gov * http://www. facemakernyc. com.