Learn More
Regional cerebral blood flow (CBF), oxygen extraction ratio (OER), oxygen utilization (CMRO2) and blood volume (CBV) were measured in a group of 34 healthy volunteers (age range 22-82 yrs) using the 15O steady-state inhalation method and positron emission tomography. Between subjects CBF correlated positively with CMRO2, although the interindividual(More)
Hypercapnia induces cerebral vasodilation and increases cerebral blood flow (CBF), and hypocapnia induces cerebral vasoconstriction and decreases CBF. The relation between changes in CBF and cerebral blood volume (CBV) during hypercapnia and hypocapnia in humans, however, is not clear. Both CBF and CBV were measured at rest and during hypercapnia and(More)
The authors examined 50 patients with cerebral glioma with use of positron emission tomography (PET) and L-[methyl]-[11C]methionine to assess the grade of malignancy and the extent of cerebral glioma. Carbon-11 methionine was highly accumulated in the lesion in 31 of 32 patients with high-grade glioma and 11 of 18 patients with low-grade glioma. The rate of(More)
Radiation absorbed doses due to intravenous administration of fluorine-18-fluorodeoxyglucose in positron emission tomography (PET) studies were estimated in normal volunteers. The time-activity curves were obtained for seven human organs (brain, heart, kidney, liver, lung, pancreas, and spleen) by using dynamic PET scans and for bladder content by using a(More)
BACKGROUND Noninvasive measurements of cerebral circulation and metabolism may be useful for diagnosis in patients with brain tumors. The authors tested the prognostic significance of circulatory and metabolic values or ratios determined by positron emission tomography (PET) in patients with gliomas. METHODS The subjects were 23 patients, who underwent a(More)
In quantitative functional neuroimaging with positron emission tomography (PET) and magnetic resonance imaging (MRI), cerebral blood volume (CBV) and its three components, arterial, capillary, and venous blood volumes are important factors. The arterial fraction for systemic circulation of the whole body has been reported to be 20-30%, but there is no(More)
PURPOSE To evaluate the usefulness of fluid-attenuated inversion recovery (FLAIR) magnetic resonance (MR) imaging sequences in the detection of acute subarachnoid hemorrhage (SAH). MATERIALS AND METHODS MR imaging with FLAIR sequences was performed with a 0.5-T superconducting unit in 20 patients (aged 30-72 years) with acute SAH due to a ruptured(More)
PURPOSE To evaluate fluid-attenuated inversion-recovery (FLAIR) magnetic resonance (MR) imaging in the detection of subacute and chronic subarachnoid hemorrhage. MATERIALS AND METHODS The authors performed 19 FLAIR MR imaging examinations at 0.5 T in 14 adult patients with subarachnoid hemorrhage 3-45 days after the ictus and 22 FLAIR examinations in 22(More)
To predict the nature of non-calcifying lung tumors, we performed a prospective study of 46 cases with L-[methyl 11C]methionine (MET, 24 cases) and 18F-fluorodeoxyglucose (FDG, 22 cases) using positron emission tomography (PET). Mean tumor/muscle radioactivity ratios are 5.3 +/- 2.0 (n = 14) for malignant and 1.9 +/- 0.9 (n = 10) for benign with MET (p less(More)
Abnormalities in the oxidative metabolism of glucose in human cerebral gliomas have been studied in seven patients using positron emission tomography. Measurements of regional cerebral blood flow and oxygen consumption were obtained using the oxygen-15 steady-state inhalation technique. Values of regional cerebral glucose consumption were obtained using(More)