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PT  - JOURNAL ARTICLE
AU  - Hirai, T.
AU  - Kitajima, M.
AU  - Nakamura, H.
AU  - Okuda, T.
AU  - Sasao, A.
AU  - Shigematsu, Y.
AU  - Utsunomiya, D.
AU  - Oda, S.
AU  - Uetani, H.
AU  - Morioka, M.
AU  - Yamashita, Y.
TI  - Quantitative Blood Flow Measurements in Gliomas Using Arterial Spin-Labeling at 3T: Intermodality Agreement and Inter- and Intraobserver Reproducibility Study
AID  - 10.3174/ajnr.A2725
DP  - 2011 Dec 01
TA  - American Journal of Neuroradiology
PG  - 2073--2079
VI  - 32
IP  - 11
4099  - http://www.ajnr.org/content/32/11/2073.short
4100  - http://www.ajnr.org/content/32/11/2073.full
SO  - Am. J. Neuroradiol.2011 Dec 01; 32
AB  - BACKGROUND AND PURPOSE: QUASAR is a particular application of the ASL method and facilitates the user-independent quantification of brain perfusion. The purpose of this study was to assess the intermodality agreement of TBF measurements obtained with ASL and DSC MR imaging and the inter- and intraobserver reproducibility of glioma TBF measurements acquired by ASL at 3T. MATERIALS AND METHODS: Two observers independently measured TBF in 24 patients with histologically proved glioma. ASL MR imaging with QUASAR and DSC MR imaging were performed on 3T scanners. The observers placed 5 regions of interest in the solid tumor on rCBF maps derived from ASL and DSC MR images and 1 region of interest in the contralateral brain and recorded the measured values. Maximum and average sTBF values were calculated. Intermodality and intra- and interobsever agreement were determined by using 95% Bland-Altman limits of agreement and ICCs. RESULTS: The intermodality agreement for maximum sTBF was good to excellent on DSC and ASL images; ICCs ranged from 0.718 to 0.884. The 95% limits of agreement ranged from 59.2% to 65.4% of the mean. ICCs for intra- and interobserver agreement for maximum sTBF ranged from 0.843 to 0.850 and from 0.626 to 0.665, respectively. The reproducibility of maximum sTBF measurements obtained by methods was similar. CONCLUSIONS: In the evaluation of sTBF in gliomas, ASL with QUASAR at 3T yielded measurements and reproducibility similar to those of DSC perfusion MR imaging. AIFarterial input functionASLarterial spin-labelingDSCdynamic susceptibility contrast-enhancedICCintraclass correlation coefficientQUASARquantitative STAR labeling of arterial regionsQUIPPSquantitative imaging of perfusion using a single subtractionrCBFrelative cerebral blood flowrCBVrelative cerebral blood volumesTBFstandardized TBFTBFtumor blood flow