$Unique_ID{BRK04309} $Pretitle{} $Title{Vascular Malformations of the Brain} $Subject{Vascular Malformations of the Brain Intracranial Vascular Malformations Occult Intracranial Vascular Malformations Cerebral Malformations Arteriovenous Malformations Cavernous Malformations Venous Malformations Telangiectasias Moyamoya Disease Cerebrovascular Accident (Stroke) } $Volume{} $Log{} Copyright (C) 1989 National Organization for Rare Disorders, Inc. 642: Vascular Malformations of the Brain ** IMPORTANT ** It is possible that the main title of the article (Vascular Malformations of the Brain) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Intracranial Vascular Malformations Occult Intracranial Vascular Malformations Cerebral Malformations Disorder Subdivisions: Arteriovenous Malformations Cavernous Malformations Venous Malformations Telangiectasias Information on the following diseases can be found in the Related Disorders section of this report: Moyamoya Disease Cerebrovascular Accident (Stroke) 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. Vascular Malformations of the Brain are conditions that affect the blood vessels in the brain. They may be classified into four groups: Arteriovenous Malformations (abnormal arteries and veins), Cavernous Malformations (enlarged blood-filled spaces), Venous Malformations (abnormal veins), and the Telangiectasias (enlarged capillary-sized vessels). Symptoms and progression of these disorders vary with the type and severity of the malformations. Symptoms Vascular Malformations of the Brain may cause headaches, seizures, strokes, or bleeding in the brain (cerebral hemorrhage). Some researchers believe that the type of malformation determines the symptoms and progression of the disease. Other researchers believe that only the severity rather than the type of malformation is important. Arteriovenous Malformations or AVM's affect arteries, veins, and middle- sized vessels but not capillaries. These blood vessels are enlarged and twisted. Arteries and veins may be connected directly instead of being connected through fine capillaries. (For more information on this disorder choose "Arteriovenous" for your search term in the Rare Disease Database.) Cavernous Malformations consist of abnormally enlarged collections of blood-filled spaces. Cavernous Malformations may also be called Cavernous Angiomas or Cavernous Hemangiomas. Venous Malformations involve only the veins; they vary in size but do not involve the arteries. The veins may be enlarged and twisted. These abnormal veins may compensate for a lack of normal veins in another area of the brain. Telangiectasias result from enlarged openings (dilation) of capillary- sized vessels. Telangiectasias may occur on the face, eyes, membranes that cover the brain and spinal cord (meninges), and mucous membranes (the thin moist layer lining the body's internal surfaces). Causes The cause of Vascular Malformations of the Brain may be either congenital or acquired. It may be inherited as an autosomal dominant trait with variable expression and incomplete penetrance. Human traits including the classic genetic diseases, are the product of the interaction of two genes for that condition, one received from the father and one from the mother. In dominant disorders, a single copy of the disease gene (received from either the mother or father) will be expressed "dominating" the normal gene and resulting in appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child. Incomplete penetrance means that all characteristics of a particular trait may not be manifested in all those who inherit the gene. Malformations may also be the result of an injury or trauma. Symptoms may appear because the injured blood vessels may have very small malformations or lesions, a blood clot (thrombosis) may slow the blood flow, or slight bleeding may effect nearby tissues in the brain. Affected Population Vascular Malformations of the Brain affect males and females in equal numbers. A hereditary form of Cavernous Malformations tends to occur more frequently in Mexican-Americans. Arteriovenous Malformations occur more frequently in males. Related Disorders Symptoms of the following disorders can be similar to those of Vascular Malformations of the Brain. Comparisons may be useful for a differential diagnosis: Cerebrovascular Accidents (Strokes) occur 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 usually the result of the buildup of fat-containing materials and calcium (plaque) on the inner linings of the blood vessels (atherosclerosis or hardening of the arteries). Embolic strokes occur when a clot breaks away from a diseased artery in another part of the body or the heart 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 circulating blood. Each type of stroke has its own symptoms, progression, and prognosis. Clumsiness, headaches, speech difficulties, weakness or paralysis of one or both sides of the body may occur. Stiff neck, nausea, vomiting, and loss of consciousness are also common symptoms. Moyamoya Disease is a progressive disease that effects blood vessels in the brain (cerebrovascular). It is characterized by narrowing and/or closing of the main artery to the brain (carotid) which decreases the blood supply. This lack of blood may cause semi- or complete paralysis of the feet, legs or the upper extremities. Cerebral bleeding, convulsions, headaches, various vision problems, mental deficiencies, and psychiatric problems may also occur. (For more information on this disorder, choose "Moyamoya" as your search term in the Rare Disease Database. Therapies: Standard Imaging machines such as Digital Intravenous Computerized or Common Angiography, Magnetic Resonance Imaging (MRI), Computed Tomography (CT) Scans, and Venograms can take pictures of the brain's blood vessels to see if Vascular Malformations are present. Current treatment options vary according to the severity and location of the malformation. Surgical Removal (Resection), Multiple Embolization (an operation in which pellets are put into the circulatory system in order to block the abnormal blood vessels), and Irradiation are the treatments currently in use. In some cases treatment may not be necessary. Genetic counseling may be of benefit for patients and their families if they have a hereditary form of this disorder. Other treatment is symptomatic and supportive. Therapies: Investigational Researchers are investigating several types of surgery that may be effective in treating Vascular Malformations of the Brain. Charged-Particle Radiosurgery, Interventriculostomy, and Catheter Placement are being studied. Charged-Particle Radiosurgery involves a needlelike surgical instrument which uses charged particles to cut tissue, to sterilize the edges of the wound, and to seal cut blood vessels. Interventriculostomy involves creating an opening in the brain to drain fluid. Catheters may be placed in the brain to drain any excess fluid and to collapse the malformed vessels. 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 Vascular Malformations of the Brain, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 NIH/National Institute of Neurological Disorders & Stroke (NINDS) 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5751 (800) 352-9424 For genetic information and genetic counseling referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10505 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References VASCULAR MALFORMATIONS OF THE BRAIN: B.M. Stein & J.P Mohr; N Engl J Med (August 11, 1988: issue 319(6)). Pp. 368-370. CEREBRAL CAVERNOUS MALFORMATIONS: INCIDENCE AND FAMILIAL OCCURRENCE: D. Rigamonti et al.; N Engl J Med (August 11, 1988: issue 319(6)). Pp. 343- 347. CLINICAL, RADIOLOGICAL, AND PATHOLOGICAL SPECTRUM OF ANGIOGRAPHICALLY OCCULT INTRACRANIAL VASCULAR MALFORMATIONS. ANALYSIS OF 21 CASES AND REVIEW OF THE LITERATURE: R.D. Lobato et al.; J Neurosurg (April, 1988: issue 68(4)). Pp. 518-531.