Sturge-Weber syndrome. A rare, congenital disorder that affects the brain, skin, and eyes. Abnormal blood vessel growth occurs in the trigeminal nerve in the face and the meninges (covering) of the brain. This abnormal growth causes red or purple skin discoloration (sometimes called a port wine stain), usually on one side of the face, and can also cause seizures, learning disabilities, and glaucoma. Also called Sturge-Weber syndrome.