Moyamoya disease is a rare blood vessel (vascular) disorder in which a ring of blood vessels at the base of your brain (the circle of Willis) and the uppermost (distal) segments of the arteries supplying the brain progressively narrow, causing blood flow to your brain to become reduced.ppointments at Mayo Clinic Mayo Clinic offers appointments in Arizona, Florida and Minnesota and at Mayo Clinic Health System locations.
Antithrombotic An antithrombotic agent is a drug that reduces the formation of blood clots ( thrombi). Antithrombotics can be used therapeutically for prevention ( primary prevention, secondary prevention) or treatment of a dangerous blood clot (acute thrombus).
Antinuclear Antibodies (ANA). Guide. An antinuclear antibody (ANA) test measures the amount and pattern of antibodies in your blood that work against your own body (autoimmune reaction). The body's immune system normally attacks and destroys foreign substances such as bacteria and viruses.n antinuclear antibodies (ANA) test is done to help identify problems with the immune system, such as: 1  Rheumatoid arthritis. 2  Systemic lupus erythematosus (SLE). 3  Polymyositis.