Information on the following diseases can be found in the Related Disorders section of this report:

• Meige Syndrome
• Tardive Dyskinesia
• Wilson's Disease
• Tourette Syndrome
• Tetany
• Tetanus

In the early stages, benign essential blepharospasm is characterized by frequent or forced blinking and eye irritation that often occurs as a result of specific stimuli including bright lights, fatigue, emotional tension, and environmental factors such as wind or air pollution. BEB virtually always affects both eyes (bilateral).

The frequency of muscle spasms and contractions may increase causing involuntary narrowing of the opening between the eyelids or closure of the eyelids. It may become progressively harder for affected individuals to keep their eyes open. In severe cases, the spasms may intensify to the point where the eyelids are closed several hours at a time. Although an individual's vision remains unaffected, prolonged closure of the eyelids may cause a person to become functionally blind.

BEB may occur in association with dystonia of the lower part of the face, mouth or jaw. In these cases, BEB may be associated with jaw clenching, grimacing or tongue protrusion. This is called Meige syndrome. BEB may also be associated with abnormally dry eyes.

In most cases, spasms and contractions occur during the daytime and disappear while the individual is sleeping, only to recur the next day. Symptoms of BEB may be temporarily alleviated by a variety of activities including singing, laughing, yawning, and chewing.

Other activities may worsen symptoms. Such activities include reading, walking, watching television, exposure to bright lights, and driving. Stress may also worsen symptoms.

The cause of benign essential blepharospasm is unknown. Researchers speculate that the cause of BEB may be multifactorial (e.g., caused by the interaction of certain genetic and environmental factors).

Malfunctioning of a region of the brain known as the basal ganglia may play a role in the development of BEB. The basal ganglia is a structure composed of nerve cells located deep in the brain. The basal ganglia is involved in the regulation of motor and learning functions. The exact problem(s) associated with the basal ganglia in individuals with BEB is unknown.

In some cases, BEB runs in families. In these rare instances, it is more obvious that BEB may be inherited. More study is required to determine the exact role genetics plays in the development of BEB.

In some cases, affected individuals may have a history of eye trauma. However, no proven relationship between eye trauma and the development of BEB has been established. In most cases, BEB develops spontaneously with no known precipitating factor.

BEB may occur secondary to other disorders such as tardive dystonia, Wilson disease, and various parkinsonian syndromes. BEB may also occur secondary to the use of certain drugs specifically the drugs used to treat Parkinson's disease.

Benign essential blepharospasm affects women more often than men. The average age of onset is 56.

It is estimated that approximately 2,000 new cases of BEB are diagnosed each year in the United States. The prevalence of BEB in the general population is approximately 5 per 100,000 individuals.

Symptoms of the following disorders can be similar to those of benign essential blepharospasm. Comparisons may be useful for a differential diagnosis:

Meige syndrome is a rare neurological disorder that is characterized by spasms of all the muscles of the face, including the tongue and jaw. People in late middle age are most often affected. Just as in blepharospasm, involuntary eyelid closure may result from spasms of the muscles around the eyes. (For more information on this disorder, choose "Meige Syndrome" as your search term in the Rare Disease Database.)

Bell's palsy is a nonprogressive neurological disorder of one of the facial nerves (7th cranial nerve). This disorder is characterized by the sudden onset of facial paralysis only on one side that may be preceded by a slight fever, pain behind the ear on the affected side, or a stiff neck. The exact cause of Bell's palsy is not known, but viral (e.g., herpes zoster virus) and immune disorders are frequently implicated as a cause for this disorder. There may also be an inherited tendency toward developing Bell's palsy. (For more information on this disorder, choose "Bell's palsy" as your search term in the Rare Disease Database.)

Dystonia is a group of neurological movement disorders characterized by involuntary muscle contractions. Dystonia may be focal (affecting an isolated body part), segmental (affecting adjacent body areas, or generalized (affecting many major muscle groups simultaneously). Dystonia may result in abnormal, often painful movements or postures. When dystonia is generalized, it may include blepharospasm. There are many different causes for dystonia. Genetic as well as non-genetic factors contribute to all forms of dystonia. (For more information on this disorder, choose "dystonia" as your search term in the Rare Disease Database.)

Hemifacial spasm, which is characterized by spasmodic contractions on one side of the face, is not a form of dystonia. The initial symptom of hemifacial spasm may be twitching of the eyelids that eventually results in brief forced closure of the eyelid. Hemifacial spasm may be caused by pressure on or irritation of the facial nerve. Hemifacial spasm is only rarely bilateral, and when it is, the spasms are not synchronous on the two sides of the face. (For more information on this disorder, choose "Hemifacial Spasm" as your search term in the Rare Disease Database.)

Diagnosis
No laboratory tests exist to make a definitive diagnosis of benign essential blepharospasm. A diagnosis is made based upon a thorough clinical evaluation, a detailed patient history and identification of characteristic symptoms.

Treatment
Treatment of BEB consists of oral drug therapy, focal injections of botulinum toxin (Botox or other brands) or surgery, used alone or in conjunction.

Approximately one-third of affected individuals are treated with oral medications (drug therapy) specifically anticholinergic drugs and with dopamine depleters such as tetrabenazine. The results of these drug treatments are usually moderate or unsatisfactory and often temporary. Additional drugs that have been used to treat BEB include clonazepam, trihexyphenidyl, diazepam, and baclofen.

Botulinum A toxin (BOTOX) has been approved by the Food and Drug Administration (FDA) as a treatment for blepharospasm and has become the primary form of treatment. The technique of injecting small amounts of botulinum toxin into the orbicularis oculi weakens these muscles for several months, after which time the procedure must be repeated. Botulinum toxin injections have been helpful for many individuals with blepharospasm, but some people do not respond well. The drug is distributed by Allergan, Inc. For more information patients should ask their physician to contact: Allergan Inc., 2525 Dupont Drive, Irvine, CA 92713-9534.

Two surgical approaches are in use in cases in which drug therapy does not work. In a procedure called a protractor myectomy, the eyelid muscles themselves are destroyed. A myectomy may involve partial or complete removal of the muscles responsible for eyelid closure.

In the past a procedure known as a neurectomy was performed to treat individuals with BEB. However, the complication rate is much higher than with a myectomy and this procedure is rarely used anymore. In a neurectomy, sections are taken off the branches of the facial nerve leading to the orbicularis oculi. Paralysis of the entire upper face may result, but the nerve branches tend to regenerate after a period of months or years.

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:
www.centerwatch.com

TEXTBOOKS
DeLong M. Blepharospasm. In: NORD Guide to Rare Disorders. Lippincott Williams & Wilkins. Philadelphia, PA. 2003:610.

Kanski JJ., ed. Clinical Ophthalmology, 4th ed. Woburn, MA: Butterworth-Heinemann; 1999:639.

Newell FW. Ophthalmology: Principles and Concepts.7th ed. St. Louis, MO: Mosby Year Book;1991:194.

JOURNAL ARTICLES
Hallett M. Blepharospasm: recent advances. Neurology. 2002;59:1306-12.

Drummond GT, Hinz BJ. Botulinum toxin for blepharospasm and hemifacial spasm: stability of duration of effect and dosage over time. Can J Ophthalmol. 2001;36:398-403.

Esmaeli-Gutstein B, Nahmias C, Thompson M, Kazdan M, Harvey J. Position emission in tomography in patients with benign essential blepharospasm. Ophthal Plast Reconstr Surg. 1999;15:23-7.

Anderson RL, Patel BC, Holds JB, Jordan DR. Blepharospasm: past, present, and future. Ophthal Reconstr Surg. 1998;15:305-17.

Hasan SA, Baker RS, Sun WS, et al., The role of blink adaption in the pathophysiology of benign essential blepharospasm. Arch Ophthalmol. 1997;115:631-6.

Scheidt CE, Schuller B, Rayki O, Kommerell G, Deuschl G. Relative absence of psychopathology in benign essential blepharospasm and hemifacial spasm. Neurology. 1996;47:43-5.

Ainsworth JR, Kraft SP. Long-term changes in duration of relief with botulinum toxin treatment of essential blepharospasm and hemifacial spasm. Ophthalmology. 1995;102:2036-40.

Holds JB, White GL Jr., Thiese SM, Anderson RL. Facial dystonias, essential blepharospasm and hemifacial spasm. Am Fam Physician. 1991;43:2113-20.

Wirtschafter JD. Clinical doxorubicin chemomyectomy. An experimental treatment for benign essential blepharospasm and hemifacial spasm. Ophthalmology. 1991;98:357-66.

Waddy HM, Fletcher NA, Harding AE, Marsden CD. A genetic study of idiopathic focal dystonias. Annals Neurology. 1991;29:320-4.

Kraft SP, Lang AE. Cranial dystonia, blepharospasm and hemifacial spasm: clinical features and treatment, including the use of botulinum toxin. Can Med Assoc J. 1988;139:837-44.

Dutton JJ, Buckley EG. Botulinum toxin in the management of blepharospasm. Arch Neurol. 1986;43:380-2.

FROM THE INTERNET
Saulny SM. Benign Essential Blepharospasm. emedicine. Last Updated: August 8, 2005. 9pp. Available at: http://www.emedicine.com/OPH/topic202.htm

McKusick VA, Ed. Online Mendelian Inheritance in Man (OMIM). The Johns Hopkins University. Benign Essential Blepharospasm. Entry No: 606798. Last Updated: February 11, 2004. Available at: http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=606798

WE MOVE Web site. Blepharospasm. Last Updated: January 19, 2005. Available at: http://www.wemove.org/dys/dys_fbleph.html

National Institute of Neurological Disorders and Stroke (NINDS). Benign Essential Blepharospasm Information Page. Last Updated: January 23, 2006. Available at: http://www.ninds.nih.gov/disorders/blepharospasm/blepharospasm.htm