Abnormal cerebral hemodynamics in pregnancy-related hypertensive encephalopathy.

A patient with an imminent pregnancy-related hypertensive encephalopathy is presented in whom transcranial Doppler ultrasound studies revealed increased middle cerebral artery blood flow velocities before and up to 7 days after cesarean section. These increased velocities are normally caused by cerebral vasospasm and subsequent hypoperfusion in pregnancy-related hypertensive encephalopathy. Additional duplex volume flow studies of the common carotid artery were in favor of cerebral hyperperfusion as a cause of the increased blood flow velocities. The clinical implications of these findings are discussed.