skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique

Abstract

A study with positron emission tomography (PET) was performed on 10 patients with ischemic stroke and mild disability. The patients underwent cerebral angiography, x-ray computed tomography (CT) scan and regional cerebral measurements of CBF, CMRO2, oxygen extraction ratio (OER), and cerebral blood volume (CBV). Only minor arterial involvement was detected by angiography. In all patients, PET images of functional defects were more extensive than the corresponding CT hypodensity, and there were statistically significant reductions in CBF, CMRO2, and CBF/CBV ratio as compared with control subjects. Half of the regions analyzed in the affected hemisphere demonstrated a disruption of the normal coupling between CBF and CMRO2 as reflected by OER values significantly higher or lower than those of the corresponding region of the contralateral hemisphere. The pathophysiological pattern of high OER combined with a reduction in CBF proportionally greater than the reduction in CMRO2 was particularly indicative of regional chronic hemodynamic compromise in these patients.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Research Institute for TB and Cancer, Sendai, Japan
OSTI Identifier:
6791037
Alternate Identifier(s):
OSTI ID: 6791037
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Cereb. Blood Flow Metab.; (United States); Journal Volume: 2
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; BRAIN; POSITRON COMPUTED TOMOGRAPHY; ISCHEMIA; PATHOGENESIS; BIOMEDICAL RADIOGRAPHY; CAT SCANNING; DYNAMIC FUNCTION STUDIES; OXYGEN 15; OXYGEN ENHANCEMENT RATIO; PATIENTS; BETA DECAY RADIOISOTOPES; BETA-PLUS DECAY RADIOISOTOPES; BODY; CARDIOVASCULAR DISEASES; CENTRAL NERVOUS SYSTEM; COMPUTERIZED TOMOGRAPHY; DIAGNOSTIC TECHNIQUES; DISEASES; EMISSION COMPUTED TOMOGRAPHY; EVEN-ODD NUCLEI; ISOTOPES; LIGHT NUCLEI; MEDICINE; MINUTES LIVING RADIOISOTOPES; NERVOUS SYSTEM; NUCLEAR MEDICINE; NUCLEI; ORGANS; OXYGEN ISOTOPES; RADIOISOTOPES; RADIOLOGY; TOMOGRAPHY; VASCULAR DISEASES 550601* -- Medicine-- Unsealed Radionuclides in Diagnostics; 550602 -- Medicine-- External Radiation in Diagnostics-- (1980-)

Citation Formats

Pozzilli, C., Itoh, M., Matsuzawa, T., Fukuda, H., Abe, Y., Sato, T., Takeda, S., and Ido, T. Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique. United States: N. p., 1987. Web. doi:10.1038/jcbfm.1987.36.
Pozzilli, C., Itoh, M., Matsuzawa, T., Fukuda, H., Abe, Y., Sato, T., Takeda, S., & Ido, T. Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique. United States. doi:10.1038/jcbfm.1987.36.
Pozzilli, C., Itoh, M., Matsuzawa, T., Fukuda, H., Abe, Y., Sato, T., Takeda, S., and Ido, T. Wed . "Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique". United States. doi:10.1038/jcbfm.1987.36.
@article{osti_6791037,
title = {Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique},
author = {Pozzilli, C. and Itoh, M. and Matsuzawa, T. and Fukuda, H. and Abe, Y. and Sato, T. and Takeda, S. and Ido, T.},
abstractNote = {A study with positron emission tomography (PET) was performed on 10 patients with ischemic stroke and mild disability. The patients underwent cerebral angiography, x-ray computed tomography (CT) scan and regional cerebral measurements of CBF, CMRO2, oxygen extraction ratio (OER), and cerebral blood volume (CBV). Only minor arterial involvement was detected by angiography. In all patients, PET images of functional defects were more extensive than the corresponding CT hypodensity, and there were statistically significant reductions in CBF, CMRO2, and CBF/CBV ratio as compared with control subjects. Half of the regions analyzed in the affected hemisphere demonstrated a disruption of the normal coupling between CBF and CMRO2 as reflected by OER values significantly higher or lower than those of the corresponding region of the contralateral hemisphere. The pathophysiological pattern of high OER combined with a reduction in CBF proportionally greater than the reduction in CMRO2 was particularly indicative of regional chronic hemodynamic compromise in these patients.},
doi = {10.1038/jcbfm.1987.36},
journal = {J. Cereb. Blood Flow Metab.; (United States)},
number = ,
volume = 2,
place = {United States},
year = {Wed Apr 01 00:00:00 EST 1987},
month = {Wed Apr 01 00:00:00 EST 1987}
}
  • Initial results in over 50 patients with stroke suggest that positron images made during continuous inhalation of carbon dioxide labeled with oxygen 15 and molecular oxygen labeled with oxygen 15 provide data on tissue function that may be relevant to acute stroke management. Five cases illustrate the following findings: 15O-activity patterns observed in areas of ischemic injury or infarction are what one would expect if the 15O distributions represented physiologic functions, such as cerebral blood flow and metabolism. Areas of abnormal 15O activity correlate with the clinical or computed tomographic (CT) localization of the deficit. In studies performed acutely, changesmore » in 15O distributions anticipate alterations in CT scans and may be predictive of outcome. Data related to oxygen metabolism correlate better with tissue viability than do those reflecting cerebral blood flow.« less
  • Although the (/sup 18/F)-2-fluoro-2-deoxyglucose positron emission tomographic technique for measuring regional glucose metabolic rate has been successfully employed for neurobehavioral studies, the long (greater than 30 min) equilibration time required may complicate the interpretation of experimental results. Positron emission tomography neurobehavioral protocols employing the continuous inhalation of CO/sup 15/O and /sup 19/Ne were developed for measuring regional cerebral blood flow during multiple control and stimulation periods. Timing, lung absorbed dose, statistical accuracy, and resolution were considered. Studies with /sup 19/Ne require shorter equilibration and stimulation times than do CO/sup 15/O studies but entail higher absorbed doses and yield poorer imagingmore » statistics.« less
  • Regional cerebral blood flow and oxygen utilisation can be measured using positron emission tomography and the continuous inhalation of /sup 15/O-labelled carbon dioxide and molecular oxygen. However, there is concern about the propagation of errors in this technique. This arises from statistical uncertainties, inherent in the transmission and emission scans, being amplified in the steady state model used for calculating the physiological parameters. The magnitude of this effect has been studied using a series of repeat transmission and emission phantom measurements in which pixel count densities equivalent to those seen in the clinical data were recorded. These measurements have beenmore » used to determine the final propagated errors that occur in the calculated values of regional cerebral blood flow, oxygen extraction fraction, and oxygen utilisation rate.« less
  • Seventy measurements of CBF were performed in 12 stroke patients by /sup 133/Xe inhalation and a rapidly rotating single photon emission computerized tomograph. CBF was measured every other day during the acute phase and at 2- and 6-month follow-up visits. A persistent contralateral cerebellar blood flow depression was evident in five patients with severe hemispheric low flow areas, which correlated with large, hypodense lesions on the computerized tomographic scan. In a sixth patient with a small, deep infarct, a transient crossed cerebellar low flow was observed, while the clinical symptoms persisted. It is concluded from this serial study that crossedmore » cerebellar diaschisis is a common finding in completed stroke. It is probably caused by disconnection of the corticopontine pathways, a disconnection that tends to persist. The phenomenon is in fact less variable than the stroke-related CBF changes in the infarcted hemisphere, in which a period of relative hyperemia is frequently seen.« less
  • Symmetries and asymmetries in regional cerebral blood flow (rCBF) determinations are reported in eleven patients with symptomatic carotid artery occlusive disease. Flourine-18-fluoromethane rCBF values are obtained by means of a noninvasive positron emission tomographic (PET) technique during room air (RA) and following induced hypercapnia (CO/sub 2/). Areas of abnormal CO/sub 2/ reactivity predict both the hemodynamic significance of the vascular lesion in question and the areas most vulnerable for ischemic infarction. This data is intended to be preliminary in nature; future expansions of this data base will be made to include rCBF/CO/sub 2/ estimations, rCBF/glucose metabolism determinations, and rCBF/reserve evaluationsmore » over time and following brain-specific therapies. Once established, the potential viability and reversibility of these ischemic, uninfarcted or minimally infarcted areas can then be reestablished over time, thus providing a quantitative measure of the natural history of flow/metabolic coupling or uncoupling.« less