NONINVASIVE DIAGNOSIS IN CEREBRAL-ISCHEMI A BY MEANS OF MAGNETIC-RESONANCE-IMAGING AND NEAR-INFRARED SPECTROSCOPY

We describe the non-invasive assessment of cerebrovascular reserve cap acity by means of near-infrared spectroscopy (NIRS) and magnetic reson ance imaging. Both methods are compared with transcranial Doppler sono graphy. There is a good correlation of the three methods in the change s in cerebral oxygen saturation and in blood velocity following acetaz olamide stimulation of cerebral blood flow, except found in one patien t with unilateral carotid artery occlusion. In this patient we found a decreased cerebrovascular reserve capacity, revealed by a magnetic re sonance technique designed to quantify CBV and CBF. We postulate a rai sed oxygen extraction as the cause of his changes in oxygen saturation .