Moyamoya Disease

The above image shows the Circle of Willis and highlights the internal carotid arteries which is the most common place for blockages causing Moyamoya disease. (neurosurgery.ufl.edu)

The above image is an angiogram showing collateral vessels that have an appearance of a "puff of smoke" as coined by the Japanese. (depts.washington.edu)

Moyamoya Disease

This disease is said to be inherited and first appeared in the Japanese. Moyamoya disease is caused by some sort of blockage or clot in the arteries leading up into the brain. The internal carotid arteries are the most common arteries to become blocked, but this disease also affects the middle and anterior cerebral arteries. Unlike atherosclerosis, the artery wall actually overgrows inward to constrict the artery. It is because of this blockage, which can also develop clots, that the blood vessels start to develop new pathways to find ways to still get the blood to the brain. These pathways are called "collateral circulation." This collateral circulation appears like a "puff of smoke" on an MRI/MRA scan.

Symptoms of Moyamoya Disease

Although this disease originated in Japan, other parts of the world have become affected as well. In the United States, women in their 30's and 40's are most affected. Children and patients with down syndrome, neurofibromatosis, or sickle cell disease can acquire Moyamoya as well. In children, Moyamoya causes strokes or seizures, and in adults it can cause strokes, bleeding, numbness in the extremities, convulsions, and migraine-like headaches. Their are also times when no symptoms will appear and death could be right around the corner.

Treatment options

The natural history of this disorder is not well known. However, several treatment options have become available to prolong the life of patients with Moyamoya. As always, patients who are eligible can take anti-platelets to help prevent clots. Some of the more common surgery treatment options are more recommended though. Encephaloduroarteriosynangiosis (EDAS) is a procedure in which a scalp artery is dissected over a course of several inches and then a small opening in the skull is made directly below the artery. The artery is then sutured to the surface of the brain and the bone is replaced to the skull. Ensephalomyosynangiosis (EMS) and Superficial Temporal Artery (STA)- Middle Cerebral Artery (MCA) bypass are also similar surgery options in which the goal is to bypass the blockage and still be able to deliver blood to the brain by means of arteries.

References

Moyamoya disease. (2010). Wikipedia.com Retrieved March 29, 2010 from http://en.wikipedia.org/wiki/Moyamoya_disease

Circle of Willis. (2009). Google images. Retrieved March 29, 2010 from http://images.google.com/imgres?imgurl=http://www.neurosurgery.ufl.edu/patients/images/circle-of-willis.jpg&imgrefurl=http://www.neurosurgery.ufl.edu/patients/moyamoya-disease.shtml&usg=__MKpbJVa7wW5xLlqsmbI2X3taK5Q=&h=272&w=285&sz=16&hl=en&start=7&um=1&itbs=1&tbnid=zs7fR6hg07JrWM:&tbnh=110&tbnw=115&prev=/images%3Fq%3Dmoya%2Bmoya%2Bdisease%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1T4ACAW_enUS314US314%26tbs%3Disch:1

Angiogram. (2009). Google images. Retrieved March 29, 2010 from http://images.google.com/imgres?imgurl=http://depts.washington.edu/neurosur/ptcare/images/sekhar/moya_images/lateral_moya.jpg&imgrefurl=http://depts.washington.edu/neurosur/ptcare/moyamoya.html&usg=__zMZ3mTYSnXIA-mOu-RkoJ-j_SlI=&h=341&w=341&sz=55&hl=en&start=1&um=1&itbs=1&tbnid=0zrV1hm_F10JDM:&tbnh=120&tbnw=120&prev=/images%3Fq%3Dmoya%2Bmoya%2Bdisease%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1T4ACAW_enUS314US314%26tbs%3Disch:1