Vascular MR contrast enhancement in cerebrovascular disease.

PURPOSE To determine the significance of vascular enhancement in stroke patients with and without permanent neurologic deficit. METHODS We prospectively studied two groups of patients with spin-echo MR imaging before and after injection of gadopentetate dimeglumine. In the patients in group 1 (12 women, 22 men; age range, 32 to 76 years), who had permanent neurologic deficit caused by recent ischemic brain infarction, we obtained 3 to 13 serial MR images during follow-up examination. Group 2 consisted of 26 patients (14 women, 12 men; age range, 54 to 81 years) with transient neurologic deficit caused by angiographically proved high-grade stenosis or occlusion of the internal carotid artery. RESULTS Vascular enhancement was present in 59% of patients in group 1 and in 65% of patients of group 2. In group 1, the frequency of vascular enhancement declined steadily over several weeks, but it was still present in single cases even after 3 months. Vascular enhancement correlated positively with the extent of brain infarction in group 1 and with the degree of carotid stenosis in group 2. CONCLUSION Vascular enhancement as shown by MR imaging may herald ischemic brain infarction and could persist over several weeks in areas that show collateral flow after infarction has occurred.