Combined magnetic resonance imaging and proton magnetic resonance spectroscopy of patients with acute stroke.
OBJECTIVE
The prospect for a therapeutic window for treatment of ischemic stroke encourages the noninvasive investigation of metabolic changes in acute ischemia. Recently, localized proton spectroscopy became available at 1.5-T magnetic resonance systems. In this study we evaluated the usefulness of combined magnetic resonance imaging and spectroscopy on the diagnosis of acute and chronic infarctions.


METHODS
Combined magnetic resonance imaging and spectroscopy investigations were carried out with a 1.5-T system in 16 volunteers, eight patients with chronic infarction (greater than 8 months), and 10 patients with acute ischemic stroke (less than 8 hours). We used a stimulated echo sequence to acquire localized spectra from image-guided volumes of interest (16-27 ml).


RESULTS
There were no significant interindividual differences of choline, creatine, phosphocreatine, and N-acetyl aspartate resonances in the spectra from volunteers. In chronic infarctions, N-acetyl aspartate was decreased in relation to choline. Acute ischemic infarctions were characterized by decreased N-acetyl aspartate resonances and elevation of lactate.


CONCLUSIONS
The study demonstrates the feasibility of proton spectroscopy in stroke patients. Metabolic alterations in ischemic tissue can be monitored and can distinguish acute from chronic lesions.
Felber
S R
SR
Department of Magnetic Resonance, University of Innsbruck, Austria.
Aichner
F T
FT
Sauter
R
R
Gerstenbrand
F
F
D000368:Aged; D001921:Brain / Q000473:pathology*; D002561:Cerebrovascular Disorders / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged