Spontaneous intracerebral hemorrhage.

ONTRAUMATIC intracerebral hemorrhage is bleeding into the parenchyma of the brain that may extend into the ventricles and, in rare cases, the subarachnoid space. Each year, approximately 37,000 to 52,400 people in the United States have an intracerebral hemorrhage. 1,2 This rate is expected to double during the next 50 years as a result of the increasing age of the population and changes in racial demographics. Intracerebral hemorrhage accounts for 10 to 15 percent of all cases of stroke and is associated with the highest mortality rate, with only 38 percent of affected patients surviving the first year. 3 Depending on the underlying cause of bleeding, intracerebral hemorrhage is classified as either primary or secondary. Primary intracerebral hemorrhage, accounting for 78 to 88 percent of cases, originates from the spontaneous rupture of small vessels damaged by chronic hypertension or amyloid angiopathy. 4 Secondary intracerebral hemorrhage occurs in a minority of patients in association with vascular abnormalities (such as arteriovenous malformations and aneurysms), tumors, or impaired coagulation. Although hypertensive intracerebral hemorrhage remains the most common form of intracerebral hemorrhage, underlying vascular abnormalities should always be considered in appropriate circumstances because of the high risk of recurrent hemorrhage and available treatment options. 5-11 The causes of intracerebral hemorrhage are shown in Table 1. We will discuss primary, or spontaneous, intracerebral hemorrhage in this review. N