$Unique_ID{BRK04011} $Pretitle{} $Title{Moyamoya Disease} $Subject{Moyamoya Disease Moya Moya Disease Moya-moya Disease Moyamoya Syndrome Cerebrovascular Moyamoya Disease Cerebrovascular Accident (CVA) or (Stroke) Cerebral Vascular Malformations } $Volume{} $Log{} Copyright (C) 1989 National Organization for Rare Disorders, Inc. 617: Moyamoya Disease ** IMPORTANT ** It is possible that the main title of the article (Moyamoya Disease) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Moya Moya Disease Moya-moya Disease Moyamoya Syndrome Cerebrovascular Moyamoya Disease Information on the following diseases can be found in the Related Disorders section of this report: Cerebrovascular Accident (CVA) or (Stroke) Cerebral Vascular Malformations General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Moyamoya disease is a progressive disease that effects the blood vessels in the brain (cerebrovascular). It is characterized by narrowing and/or closing of the main artery to the brain (carotid). This lack of blood may cause paralysis of the feet, legs or the upper extremities. Headaches, various vision problems, mental retardation, and psychiatric problems may also occur. Symptoms Moyamoya disease may occur at any age. The age of onset tends to determine the various symptoms. Cerebral bleeding (hemorrhage) and anemia, headaches, speech disorders, and sudden onsets of recurrent paralysis usually occur in juvenile Moyamoya patients. Children afflicted with Moyamoya disease may have convulsions or involuntary movements. Some may show signs of mental retardation. Patients tend to develop one or more of the following visual disturbances: blindness in one half of the visual field of one or both eyes (hemianopia), double vision (diplopia), bilaterally (right and left) decreased visual clearness (acuity), and the inability to recognize objects. Fainting, intracranial hemorrhage below the middle covering of the brain (subarachnoid) followed by accumulation of excessive amounts of watery fluid in the optic disks (papilledema) may also occur. Neurosis (mainly anxiety) usually occurs in adult Moyamoya patients. Patients usually have sudden insufficiencies of blood supplies in the brain (cerebral infarctions) which can lead to brain tissue death. Causes The exact cause of Moyamoya disease is not known. It is thought to be inherited as an autosomal recessive trait in a small number of cases. (Human traits including the classic genetic diseases, are the product of the interaction of two genes, one received from the father and one from the mother. In recessive disorders, the condition does not appear unless a person inherits the same defective gene for the same trait from each parent. If one receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will show no symptoms. The risk of transmitting the disease to the children of a couple, both of whom are carriers for a recessive disorder, is twenty-five percent. Fifty percent of their children will be carriers, but healthy as described above. Twenty-five percent of their children will receive both normal genes, one from each parent, and will be genetically normal.) Studies suggest oral contraceptive use may possibly contribute to a small number of Moyamoya cases in women, although this has not been definitely confirmed. Pregnancy may also contribute to the development of Moyamoya. Affected Population Moyamoya disease occurs mainly in females under the age of 20, particularly of Japanese origin. In one Japanese study, 7% of the cases were familial. Familial cases, including identical twins, have also been reported in Europe. Related Disorders Symptoms of the following disorders can be similar to those of Moyamoya disease. Comparisons may be useful for a differential diagnosis: A Cerebrovascular Accident (stroke) occurs because the blood supply to the brain has been cut off or decreased. Thrombotic strokes occur when a clot has narrowed or completely closed an artery in the neck or head. This is the result of the buildup of fat-containing materials and calcium (plaque) on the inner linings of the blood vessels. Embolic strokes occur when a clot breaks away from the diseased artery in another part of the body and clogs a smaller artery in the brain. Hemorrhagic strokes occur when a blood vessel ruptures in or around the brain, depriving that area of blood. Each type of stroke has its own symptoms, progression, and prognosis. Clumsiness, headaches, speech difficulties, weakness or complete paralysis of one or both sides of the body may occur. Stiff neck, nausea, vomiting, and unconsciousness are also common symptoms. Vascular malformations (abnormal blood vessels) of the brain are classified into arteriovenous malformations (abnormal arteries and veins), cavernous malformations (enlarged channels of blood vessels), venous malformations (abnormal veins), and the telangiectasias (enlarged capillary- sized vessels). Malformations in the brain may cause recurrent headaches, seizures, and hemorrhaging. Hemorrhaging in the brain may cause cerebrovascular accidents (strokes). Therapies: Standard Angiograms and Magnetic Resonance Imaging (MRI) are diagnostic tests that can show the brain's blood vessels to see if they are indicative of Moyamoya disease. Effective treatment of Moyamoya has been unsuccessful in the past; however, surgical treatment and drug therapy research is encouraging. There are five surgical treatments currently in use: Encephalomyosynangiosis (EMS), Encephaloduroarteriosynangiosis (EDAS), Encephalomyoarteriosynangiosis (EMAS), Superficial Temporal-to-Middle Cerebral Artery (STA-MA) Bypass, and Indirect Non-Bypass Revascularization. Response of patients to these complex and very complicated surgeries varies. Drug therapy now in use is intravenous administration of verapamil, a calcium-channel blocker which dilates certain blood vessels. The disease may also stabilize after a progressive course. Genetic counseling may be of benefit for patients and their families if they have the hereditary form of Moyamoya Disease. Other treatment is symptomatic and supportive. Therapies: Investigational Researchers are investigating two types of drugs that may be effective in treating Moyamoya disease: calcium-channel blockers and anti-aggregating (anti-blood clotting) drugs. This disease entry is based upon medical information available through April 1989. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Moyamoya Disease, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 Families with Moyamoya Network 14197 E. Kansas Pl., #105 Aurora, CO 80012 or 1282 Skylark Dr., RR #3 Cedar Rapids, IA 52403 (319) 362-8315 NIH/National Institute of Neurological Disorders & Stroke (NINDS) 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5751 (800) 352-9424 Children's Brain Diseases Foundation for Research 350 Parnassus, Suite 900 San Francisco, CA 94117 (415) 566-5402 (415) 565-6259 For genetic information and genetic counseling referrals, please contact: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 7th ed.: Victor A. McKusick; Johns Hopkins University Press, 1986. Pp. 1068. INTERNAL MEDICINE, 2nd Ed.: Jay H. Stein, ed.-in-chief; Little, Brown and Co., 1987. Pp. 2213-2214. CEREBRAL INFARCTION DUE TO MOYAMOYA DISEASE IN YOUNG ADULTS: A. Bruno, et al.; Stroke (July, 1988: issue 19(7)). Pp. 826-833. OCULAR SYMPTOMS OF MOYAMOYA DISEASE: S. Noda, et al.; Am J Ophthalmol (June 15,1987: issue 103(6)). Pp. 812-816. PITFALLS IN THE SURGICAL TREATMENT OF MOYAMOYA DISEASE. OPERATIVE TECHNIQUES FOR REFRACTORY CASES: S. Miyamoto et al.; J Neurosurg (April, 1988: issue 68(4)). Pp. 537-543. TREATMENT OF ACUTE DEFICITS OF MOYAMOYA DISEASE WITH VERAPAMIL: M.J. McLean et al.; Ann Acad Med Singapore (January, 1985: issue 14(1)). Pp. 65- 70.