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PT  - JOURNAL ARTICLE
AU  - Chawla, S.
AU  - Wang, S.
AU  - Wolf, R.L.
AU  - Woo, J.H.
AU  - Wang, J.
AU  - O&#039;Rourke, D.M.
AU  - Judy, K.D.
AU  - Grady, M.S.
AU  - Melhem, E.R.
AU  - Poptani, H.
TI  - Arterial Spin-Labeling and MR Spectroscopy in the Differentiation of Gliomas
AID  - 10.3174/ajnr.A0673
DP  - 2007 Oct 01
TA  - American Journal of Neuroradiology
PG  - 1683--1689
VI  - 28
IP  - 9
4099  - http://www.ajnr.org/content/28/9/1683.short
4100  - http://www.ajnr.org/content/28/9/1683.full
SO  - Am. J. Neuroradiol.2007 Oct 01; 28
AB  - BACKGROUND AND PURPOSE: Noninvasive grading of gliomas remains a challenge despite its important role in the prognosis and management of patients with intracranial neoplasms. In this study, we evaluated the ability of cerebral blood flow (CBF)-guided voxel-by-voxel analysis of multivoxel proton MR spectroscopic imaging (1H-MRSI) to differentiate low-grade from high-grade gliomas.MATERIALS AND METHODS: A total of 35 patients with primary gliomas (22 high grade and 13 low grade) underwent continuous arterial spin-labeling perfusion-weighted imaging (PWI) and 1H-MRSI. Different regions of the gliomas were categorized as “hypoperfused,” “isoperfused,” and “hyperperfused” on the basis of the average CBF obtained from contralateral healthy white matter. 1H-MRSI indices were computed from these regions and compared between low- and high-grade gliomas. Using a similar approach, we applied a subgroup analysis to differentiate low- from high-grade oligodendrogliomas because they show different physiologic and genetic characteristics.RESULTS: Choglioma (G)/white matter (WM), GlxG/WM, and Lip+LacG/CrWM were significantly higher in the “hyperperfused” regions of high-grade gliomas compared with low-grade gliomas. ChoG/WM and Lip+LacG/CrWM were also significantly higher in the “hyperperfused” regions of high-grade oligodendrogliomas. However, metabolite ratios from the “hypoperfused” or “isoperfused” regions did not exhibit any significant differences between high-grade and low-grade gliomas.CONCLUSION: The results suggest that 1H-MRSI indices from the “hyperperfused” regions of gliomas, on the basis of PWI, may be helpful in distinguishing high-grade from low-grade gliomas including oligodendrogliomas.