Contrast enhancement has been studied with computed tomography in 18 patients with brain infarction. Four patients were examined on more than one occasion. A mode of contrast medium administration has been used that results in constant blood iodine concentration during the investigation. The enhancement pattern was analyzed using a compartment model. A fast and a slow component of contrast enhancement was quantified for different parts of the infarct. Correlation with the age of the infarct confirms earlier studies, indicating a maximum enhancement at 2 to 4 weeks after the incidence of the infarct.