essential blepharospasm & hemifacial spasms
ESSENTIAL BLEPHAROSPASM & HEMIFACIAL SPASMS Thomas Bersani, MD
Essential blepharospasm and hemifacial spasms are facial muscle spasm disorders, which cause involuntary closure of the eyelid and can limit visual function. ESSENTIAL BLEPHAROSPASM is a type of dystonia or movement disorder, involving the eyelid closing muscles. Other muscles including the lower facial muscles, speech muscles of the throat, neck muscles and other muscle in the body can be affected. We all naturally blink involuntarily at a certain rate similar to the pacemaker in the heart. A chemical imbalance in part of the brain, which controls this blinking rate, is probably responsible for the increased frequency and force of eyelid closure. Although the eyes can see normally when they are open the lids are so frequently closed that for many patients this limits their ability to function. Typically the spasms occur when focusing on a specific task such as driving, reading or watching television, or under stressful circumstances. Because the early symptoms and appearance are more subtle, many patients and their doctors do not realize they have this condition. DRUGS: Many drugs have been tried to reduce the spasms. In a small percentage of patients drug therapy can be effective, but in many cases, either the drugs are ineffective or the side effects are not tolerable. Weakening of the eyelid closing muscles through either injections of Botulinum toxin or surgical removal of some of the muscle can substantially improve the symptoms of this condition without actually treating the underlying cause. BOTULINUM TOXIN or “Botox” injections: Botulinum toxin is derived from the bacteria, which causes Botulism poisoning. In its natural concentration, Botulinum toxin is deadly because it is capable or paralyzing all the muscles in the body, including the heart and lungs. When isolated, purified and diluted by 30,000 times its normal strength, it can be injected to cause localized weakness of specific muscles. It is extremely safe and has been used on thousands of patients since 1980 with no serious side effects. The injections are given in multiple locations around the eyelids and eyebrows, which causes slight discomfort and mild bruising. The medication begins working in several days and has its peak effect in two to four weeks and then lasts for two to six months. The most common side effect is temporary dryness of the eyes, which can be managed with supplemental teardrops or ointment.
Other infrequent side effects include drooping of the upper eyelid and double vision. This occurs in less than 5 percent of patients and is also temporary. SURGERY: In patients who do not respond adequately to Botulinum injections or prefer a permanent cure of their symptoms, surgery to remove some of the eyelid closing muscles in the upper eyelids, brow and outer portions of the lower eyelids can be performed (myectomy). About 50 percent of patients who have this procedure have sufficient relief from their symptoms and no further treatment is required. In the other half, supplemental surgery to remove additional muscle tissue from the lower lids or supplemental Botulinum injections are necessary. When Botulinum toxin is used, a smaller amount at less frequent intervals is required than with patients who have never had the surgery. Hemifacial spasm differs from essential blepharospasm in that it involves only half of the face and is due to an irritation of the facial nerve after it has left the brain on its way to the facial muscles. Rarely a benign tumor pressing on the nerve can be causing this and therefore, a MRI scan is usually done to check for this. In most cases no tumor exists and the cause may be a blood vessel resting on and irritating the nerve. MEDICAL TREATMENT: Treatment with medication is sometimes affective. Five percent of patients improve with the use of Tegretol (carbamazepine), a drug also used for seizure disorders. Generally, the treatment is only effective while on the medication. BOTULINUM INJECTIONS: Botulinum toxin injected into multiple locations in the eyelids and cheek can greatly reduce the spasm symptoms for two to six months. MYECTOMY SURGERY: For permanent relief of symptoms, eye closing muscle excision can also be performed similar to essential blepharospasm. The Botulinum injections and eyelid surgery usually cause some reduction in the lower facial spasms as well. NEUROLOGICAL TREATMENT: If lower facial spasms still remain very symptomatic, or if a permanent cure of all spasms is desired, a neurologic procedure can be performed in which the skull is opened up behind the ear and a small sponge is placed between the blood vessel pressing on the facial nerve and the nerve itself. This operation works in about 90 percent of patients, but with some risk of decreased hearing on the side of the surgery. The hearing on the other side is unaffected. For more information on essential blepharospasm and hemifacial spasm you can contact the Benign Essential Blepharospasm Research Foundation, a national organization designed to educate patients and doctors and to promote research. Benign Essential Blepharospasm Research Foundation, Inc, PO Box 12468 Beaumont, Texas 77726-2468 409-832-0788
PRECAUCIONES Y ADVERTENCIASEl tratamiento con antidiabéticos debe ser estrictamente controlado durante laterapia. A causa de la mejoría en el control de la glucemia, puede requerirse ajustarla dosis de los antidiabéticos orales o de la insulina. Aconsejar a los pacientes que sigan las directivas dietéticas. Pueden aumentar losefectos adversos gastrointestinales cuando la comida es rica en
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