Intracerebral hemorrhage can affect any person regardless of age, sex, or race, though it is more common in older people. Bleeding can occur in any part of the brain, and blood may accumulate in the tissues or in the subarachnoid space (space between the brain and the membranes covering the brain, the meninges). Bleeding may be isolated to part of one cerebral hemisphere (lobar intracerebral hemorrhage) or may occur in other brain structures such as the thalamus, basal ganglia, pons, or cerebellum. Intracerebral hemorrhage that is not caused by trauma most commonly occurs in the basal ganglia.
Intracerebral hemorrhage can be caused by head injury (trauma), bleeding into a tumor, abnormalities of the blood vessels (cerebral aneurysm or angioma --tumors involving the blood vessels) or an abnormality in blood clotting. When it is not caused by one of these conditions, intracerebral hemorrhage is most commonly associated with high blood pressure (hypertensive intracerebral hemorrhage). In some cases, no cause can be found.
Bleeding in the brain irritates the brain tissues, causing swelling (cerebral edema). It may collect into a mass (hematoma). Both cerebral edema and the presence of a hematoma within the brain will place increasing pressure on the brain tissues and eventually destroy them. Symptoms vary depending on the extent of damage and the location of the bleed.
Risk factors for intracerebral hemorrhage, in addition to the causative disorders, include the following:
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