Advanced

AJNR - American Journal of Neuroradiology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Kado, H. Articles by Itoh, H. Search for Related Content PubMed PubMed Citation Articles by Kado, H. Articles by Itoh, H.

American Journal of Neuroradiology 22:922-927 (5 2001)
© 2001 American Society of Neuroradiology

ARTICLE

Abnormal Magnetization Transfer Ratios in Normal-appearing White Matter on Conventional MR Images of Patients with Occlusive Cerebrovascular Disease

Hirotsugu Kado^,a, Hirohiko Kimura^a, Tatsuro Tsuchida^a, Yoshiharu Yonekura^a, Tomoo Tokime^a, Yasuhiko Tokuriki^a and Harumi Itoh^a

^a From the Department of Radiology (H.Ka., H.ki., T.Tsu., H.I.) and Biomedical Imaging Research Center (Y.Yo.), Fukui Medical University, Fukui; and Department of Neurosurgery (T.To., Y.To.), Fukui Red Cross Hospital, Fukui, Japan

BACKGROUND AND PURPOSE: Chronic hypoperfusion may cause ischemic insult in the deep white matter. The magnetization transfer phenomenon is associated with the amount and constitution of myelin. The purpose of this study was to assess the usefulness of the magnetization transfer ratio (MTR) for detecting vasculometabolic abnormalities on positron emission tomography (PET) studies in patients with unilateral severe stenosis of the internal carotid artery (ICA).

METHODS: MTR maps and PET data—including regional cerebral blood flow (rCBF), regional cerebral metabolic rate of oxygen (rCMRO₂), and regional oxygen extraction fraction (rOEF)—were investigated in 13 patients with unilateral severe stenosis of the ICA. The same regions of interest were selected in the white matter both on MTR maps and PET scans. The areas were classified into three groups based on MTR values (group 0, MTR >47.22%; group 1, MTR = 45.77% to 47.22%; group 2, MTR <45.77%), and the relationship between MTR and PET data was analyzed by means of both absolute values and asymmetric index (AI).

RESULTS: Abnormal values could not be detected in the areas classified as group 0. The areas classified as group 1 were characterized by absolutely normal values of rCMRO₂ and increased rOEF with AI, which was assessed as viable and reversible on the PET study. The areas classified as group 2 showed decreased rCMRO₂ with absolute values, which was considered irreversible in PET. A significant overall linear correlation was found between MTR and rCMRO₂ values.

CONCLUSION: Using the MTR technique to classify ischemic damage into three groups (normal, reversible, and irreversible), we found a significant correlation between the reduction of MTR and that of rCMRO₂ in white matter with ICA stenosis. We believe that the MTR technique may partly replace PET data in the assessment of ischemic injury.

This article has been cited by other articles:

				T. Tourdias, V. Dousset, I. Sibon, E. Pele, P. Menegon, J. Asselineau, C. Pachai, F. Rouanet, P. Robinson, G. Chene, et al. Magnetization Transfer Imaging Shows Tissue Abnormalities in the Reversible Penumbra Stroke, December 1, 2007; 38(12): 3165 - 3171. [Abstract] [Full Text] [PDF]

				A. Shiraishi, Y. Hasegawa, S. Okada, K. Kimura, T. Sawada, H. Mizusawa, and K. Minematsu Highly Diffusion-Sensitized Tensor Imaging of Unilateral Cerebral Arterial Occlusive Disease AJNR Am. J. Neuroradiol., June 1, 2005; 26(6): 1498 - 1504. [Abstract] [Full Text] [PDF]

				M. S. Bagary, M. R. Symms, G. J. Barker, S. H. Mutsatsa, E. M. Joyce, and M. A. Ron Gray and White Matter Brain Abnormalities in First-Episode Schizophrenia Inferred From Magnetization Transfer Imaging Arch Gen Psychiatry, August 1, 2003; 60(8): 779 - 788. [Abstract] [Full Text] [PDF]