A brain hemorrhage describes a condition of bleeding in the brain tissue or on the surface of the brain. Medical professionals refer to this as a cerebral hemorrhage, cerebral bleed, or hemorrhagic stroke. Two different types of cerebral hemorrhage exist, intracerebral hemorrhage and subarachnoid hemorrhage; the specific areas of the brain affected by the type. Twenty per cent of all strokes can blame the cause on a hemorrhage compared with ischemic strokes, which claim a blood clot to be the cause. Although a brain hemorrhage is less common than ischemic stroke, its incidence of death is usually higher.
An intracerebral hemorrhage is bleeding that happens within the brain tissue. An intracerebral hemorrhage occurs when one of the cerebral arteries in the brain bursts, and the surrounding tissue fills with blood. Frequently the cause of this type of bleed is due to a change in the arteries from chronic hypertension or high blood pressure. When the brain tissue loses its source of continuous blood supply after a bleed, some of the brain cells die, resulting in neurological deficits. The accumulation of the blood from the burst artery adds pressure, known as intracranial pressure, to the brain tissue. Depending on the amount of the increased pressure, neurological deficits will occur, and will range from mild to severe.
In some instances, a patient can die from the increased pressure, but in the cases in which patient survives, generally he or she will recover more neurological function than a patient who experiences a stroke caused by a blood clot. This is because eventually the pressure on the brain will decrease and the patient will be able to regain some of the former functions.
A subarachnoid hemorrhage occurs when a blood vessel on the brain’s surface ruptures and bleeds into the subarachnoid space, which is the space between the brain and the skull (but not into the brain itself). The most common cause of subarachnoid hemorrhagic stroke is a burst aneurysm and sometimes the rupture of an arteriovenous malformation, a congenital condition of a mass of abnormal blood vessels that communicate arteries and veins through a tangled “nest” rather than capillaries. These malformations are most likely to bleed between the ages of 10 and 55, after which time the bleeding chances diminish. When an AV malformation bleeds, it is with a limited amount of blood, as opposed to the hemorrhagic strokes caused by hypertension.