Stroke. Coloured computed tomography (CT) scan of an axial (horizontal) section through a patient's brain showing internal bleeding (yellow/orange) due to a cerebrovascular accident (CVA, stroke). The front of the brain is at top. The main mass of blood (haematoma) is at upper right. Left of this, blood abnormally fills a ruptured ventricle, and left of that, a normal ventricle (black) helps to circulate the brain's cerebrospinal fluid. This stroke occurred 15 days after drug treatment to prevent a stroke was halted. Aphasia (loss of speech) and hemiplegia (paralysis of one side of the body) occurred. Common causes of a stroke are high blood pressure and arterial disease.