Caffeine and human cerebral blood flow: a positron emission tomography study.

Abnormal cerebral blood flow in methamphetamine abusers assessed by brain perfusion single emission computed tomography

Introduction:Amphetamines are central nervous system (CNS) stimulant substances and amphetamine abuse is considered a growing problem in our country. Previous studies revealed destructive effects of amphetamines on metabolism, perfusion and structure of brain. The aim of current study was evaluating regional cerebral blood flow (rCBF) disturbances in methamphetamine (MA) abuser...

Interaction of caffeine with regadenoson-induced hyperemic myocardial blood flow as measured by positron emission tomography: a randomized, double-blind, placebo-controlled crossover trial.

Vascular reserve in chronic cerebral ischemia measured by the acetazolamide challenge test: comparison with positron emission tomography.

PURPOSE To determine the value of the acetazolamide challenge test with stable xenon-enhanced CT (Xe CT) for making therapeutic decisions in patients with chronic cerebrovascular disease. METHODS We compared the Xe CT-measured acetazolamide response with various measures obtained by positron emission tomography. We performed both a positron emission tomographic scan and a Xe CT study in 11 pa...

Changes in human regional cerebral blood flow and cerebral blood volume during visual stimulation measured by positron emission tomography.

The hemodynamic mechanism of increase in cerebral blood flow (CBF) during neural activation has not been elucidated in humans. In the current study, changes in both regional CBF and cerebral blood volume (CBV) during visual stimulation in humans were investigated. Cerebral blood flow and CBV were measured by positron emission tomography using H(2)(15)O and (11)CO, respectively, at rest and duri...

Changes in the arterial fraction of human cerebral blood volume during hypercapnia and hypocapnia measured by positron emission tomography.

Hypercapnia induces cerebral vasodilation and increases cerebral blood volume (CBV), and hypocapnia induces cerebral vasoconstriction and decreases CBV. Cerebral blood volume measured by positron emission tomography (PET) is the sum of three components, that is, arterial, capillary, and venous blood volumes. Changes in arterial blood volume (V(a)) and CBV during hypercapnia and hypocapnia were ...