Increased cerebral blood flow in preeclampsia with magnetic resonance imaging

The purpose of this study was to compare third trimester and nonpregnant cerebral blood flow of women with preeclampsia to normotensive control subjects with the use of magnetic resonance imaging techniques. Nine normotensive pregnant women and 12 untreated women with preeclampsia underwent velocity-encoded phase contrast magnetic resonance imaging of the bilateral middle and posterior cerebral arteries in the third trimester and at 6 to 8 weeks after delivery. The Student t test was used for comparison, with a probability value of <.05 considered significant. Third-trimester large cerebral artery blood flow was significantly higher in preeclampsia. Mean vessel diameter was unchanged, except for the left posterior cerebral artery. There was no difference in mean vessel diameter or cerebral blood flow between the 2 groups while the women were not pregnant. Cerebral blood flow is increased significantly in preeclampsia. We hypothesize that increased cerebral blood flow ultimately could lead to eclampsia through hyperperfusion and the development of vasogenic edema.