This Article Full Text Full Text (PDF) All Versions of this Article: 34/7/e82    most recent 01.STR.0000078659.43423.0Av1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nicoli, F. Articles by Cozzone, P.J. Search for Related Content PubMed PubMed Citation Articles by Nicoli, F. Articles by Cozzone, P.J. Related Collections Acute Cerebral Infarction Brain Circulation and Metabolism Emergency treatment of Stroke Computerized tomography and Magnetic Resonance Imaging

(Stroke. 2003;34:e82.)
© 2003 American Heart Association, Inc.

Research Reports

Metabolic Counterpart of Decreased Apparent Diffusion Coefficient During Hyperacute Ischemic Stroke

A Brain Proton Magnetic Resonance Spectroscopic Imaging Study

F. Nicoli, MD, PhD; Y. Lefur, PhD; B. Denis, MD; J.P. Ranjeva, PhD; S. Confort-Gouny, PhD P.J. Cozzone, PhD

From the Centre de Résonance Magnétique Biologique et Médicale, UMR CNRS No. 6612, Faculté de Médecine de Marseille (F.N., Y.L., B.D., J.P.R., S.C-G., P.J.C.), and Unité neuro-vasculaire, Service de Neurologie, Hôpital Sainte-Marguerite (F.N., B.D.), Marseille, France.

Correspondence to P.J. Cozzone, PhD, Centre de Résonance Magnétique Biologique et Médicale, UMR CNRS No. 6612, Faculté de Médecine de Marseille, 27 Boulevard Jean Moulin, 13005 Marseille, France. E-mail patrick.cozzone{at}medecine.univ-mrs.fr

Background and Purpose— Recent studies have shown that the brain ischemic area defined by the map of decreased apparent diffusion coefficient (ADC) obtained by diffusion-weighted imaging (DWI) during the first hours of ischemic stroke includes a significant part of ischemic penumbra. We hypothesize that the misjudgment of the final infarct size by ADC mapping may be related to a restricted ability of DWI to capture variations in the intensity of cellular suffering. In an attempt to characterize metabolically the hypoperfused brain parenchyma, we studied the relationship between ADC values and brain metabolic parameters measured by proton MR spectroscopic imaging (SI).

Methods— Six patients with hyperacute ischemic stroke were explored within the first 7 hours after onset with the use of a MR protocol including T2*-weighted MRI, DWI, SI, perfusion-weighted imaging, and MR angiography.

Results— This study demonstrates, for the first time, a wide gradient of ischemia-related metabolic anomalies within the abnormal area delineated by DWI during hyperacute ischemic stroke. In the narrow range of decreased mean ADC values (0.60 to 0.40x10^-9 m² · s^-1), a 33% decrease in mean ADC is associated with a 122% increase in lactate/N-acetyl aspartate ratio. Mean ADC values never fall below 0.40x10^-9 m² · s^-1 within the severely affected ischemic tissue, while SI still detects a large metabolic heterogeneity inside areas showing similar decreased mean ADC values close to this threshold.

Conclusions— Our results indicate that the region of very low mean ADC values observed during hyperacute ischemic stroke contains areas of various tissue damage intensity characterized by SI in relation to different stages of cellular metabolic injury. This observation may explain why ADC mapping does not reliably predict final infarct size.

Key Words: magnetic resonance imaging, diffusion-weighted • spectroscopy, nuclear magnetic resonance • stroke, acute

This article has been cited by other articles:

				S. Haik, D. Galanaud, M. G. Linguraru, K. Peoc'h, N. Privat, B. A. Faucheux, N. Ayache, J.-J. Hauw, D. Dormont, and J.-P. Brandel In Vivo Detection of Thalamic Gliosis: A Pathoradiologic Demonstration in Familial Fatal Insomnia Arch Neurol, April 1, 2008; 65(4): 545 - 549. [Abstract] [Full Text] [PDF]

				J. L. Leach, R. B. Fortuna, B. V. Jones, and M. F. Gaskill-Shipley Imaging of Cerebral Venous Thrombosis: Current Techniques, Spectrum of Findings, and Diagnostic Pitfalls RadioGraphics, October 1, 2006; 26(suppl_1): S19 - S41. [Abstract] [Full Text] [PDF]

				J. V. Guadagno, E. A. Warburton, P. S. Jones, D. J. Day, F. I. Aigbirhio, T. D. Fryer, S. Harding, C. J. Price, H. A. Green, O. Barret, et al. How affected is oxygen metabolism in DWI lesions?: A combined acute stroke PET-MR study. Neurology, September 12, 2006; 67(5): 824 - 829. [Abstract] [Full Text] [PDF]

				L. Feng, C. L. Dumoulin, S. Dashnaw, R. D. Darrow, R. L. DeLaPaz, P. L. Bishop, and J. Pile-Spellman Feasibility of Stent Placement in Carotid Arteries with Real-time MR Imaging Guidance in Pigs Radiology, February 1, 2005; 234(2): 558 - 562. [Abstract] [Full Text] [PDF]

				C. S. Kidwell, J. R. Alger, and J. L. Saver Evolving Paradigms in Neuroimaging of the Ischemic Penumbra Stroke, November 1, 2004; 35(11_suppl_1): 2662 - 2665. [Abstract] [Full Text] [PDF]