This study was performed to determine whether sympathetic stimulation reduces or redistributes cerebral blood flow. Total and regional cerebral blood flows were measured with the use of microspheres. Left stellate and superior cervical ganglia were stimulated electrically in anesthetized dogs. Sympathetic stimulation did not alter blood flow to ipsilateral cerebrum, cerebellum, or brainstem. Re...

BACKGROUND AND PURPOSE This study investigated whether in patients with internal carotid artery occlusion the regional cerebral hematocrit correlates with cerebral hemodynamics or metabolic state and, if so, how the regional cerebral hematocrit changes in the hemodynamically compromised region. METHODS We used positron emission tomography to study seven patients with unilateral internal carot...

Influence of Changes in Blood Pressure on Cerebral Oxygenation: Role of Skin Blood Flow? To the Editor: We read with interest the report from Lucas et al1 in the recent issue of Hypertension. We agree with the findings presented on cerebral blood flow with transcranial ultrasound Doppler, but we propose an alternative interpretation of the cerebral oxygenation data. As pointed out by the author...

Cerebral blood flow was determined by an N2O method in 7 normal men at sea level and after 6 to 12 hr and 3 to 5 days at 3810 m altitude. An infrared N2O analyzer was used both to measure end-tidal PN2O SO that it could be kept constant for 15 min and to determine blood N2O, for which a simple gas extraction method was devised. In addition, acute changes in cerebral blood flow were estimated fr...

Cerebral perfusion pressure was reduced by graded constricting of both carotid arteries in the anesthetized dogs, of which vertebral arteries were ligated bilaterally. Cerebral blood flow and cerebral metabolic rate of oxygen remained unchanged until cerebral perfusion pressure was lowered to about 50 mm.Hg, indicating that cerebral autoregulation was preserved normally in these animals. Despit...

We measured cerebral blood flow in 10 consecutive, but selected, patients with acute ischemic stroke (less than 48 hours after onset) before and after hemodilution. Cerebral blood flow was measured by xenon-133 inhalation and emission tomography, and only patients with focal hypoperfusion in clinically relevant areas were included. Hemodilution was done according to the hematocrit level: for a ...

Using positron emission tomography in nine patients with minor strokes, unilateral internal carotid artery occlusion, and good collateral circulation through the anterior portion of the circle of Willis, we analyzed regional cerebral blood flow, cerebral metabolic rate of oxygen, oxygen extraction fraction, and cerebral blood volume. These studies allowed quantification of the regional hemodyna...

flow during sleep and waking. J Appl Physiol 5: 620-625, 1973 15. Sakai F, Meyer JS, Karacan I, Yamaguchi F, Yamamoto M: Narcolepsy: Regional. cerebral blood flow during sleep and wakefulness. Neurology (Minneap) 29: 61-67, 1979 16. H^edt-Rassmussen K: Regional cerebral blood flow: The intraarterial injection method. Acta Neurol Scan 27: 39-41, 1967 17. Lassen NA, Ingvar DH: Radioisotopic asses...

More accurate methods for monitoring cerebral blood flow, oxygen, and glucose metabolism with results of their application in human volunteers are described. Subjects with various types of cerebral vascular disease showed decreased cerebral blood flow and oxygen and glucose metabolism but anaerobic glycolysis appeared to be increased. Inhalation of 100% oxygen decreased anaerobic glycolysis, an...

More accurate methods for monitoring cerebral blood flow, oxygen, and glucose metabolism with results of their application in human volunteers are described. Subjects with various types of cerebral vascular disease showed decreased cerebral blood flow and oxygen and glucose metabolism but anaerobic glycolysis appeared to be increased. Inhalation of 100% oxygen decreased anaerobic glycolysis, an...