Brain shunts in patients with stroke: possible cerebral autoregulation of changed haemodynamics

: The cerebral perfusion was evaluated in 8 patients with stroke, caused by stenosis or occlusion of the carotid artery, and in 4 neurologically healthy subjects, using Tc99m labeled microspheres (LMS). By measuring activity in the brain and lungs after intracarotid injection of LMS, the existence of brain shunts in patients with stroke was demonstrated. It seems that brain ischaemia triggers the opening of shunts which appear to be one of the important autoregulatory and protective mechanisms to cerebral haemodynamic changes after brain infarction.