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RT Journal Article
SR Electronic
T1 Comparison of Microvascular Permeability Measurements, K<sup>trans</sup>, Determined with Conventional Steady-State T1-Weighted and First-Pass T2*-Weighted MR Imaging Methods in Gliomas and Meningiomas
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 409
OP 417
VO 27
IS 2
A1 Cha, S.
A1 Yang, L.
A1 Johnson, G.
A1 Lai, A.
A1 Chen, M.-H.
A1 Tihan, T.
A1 Wendland, M.
A1 Dillon, W.P.
YR 2006
UL http://www.ajnr.org/content/27/2/409.abstract
AB BACKGROUND AND PURPOSE: The widely accepted MR method for quantitating brain tumor microvascular permeability, Ktrans, is the steady-state T1-weighted gradient-echo method (ssT1). Recently the first-pass T2*-weighted (fpT2*) method has been used to derive both relative cerebral blood volume (rCBV) and Ktrans. We hypothesized that Ktrans derived from the ssT1 and the fpT2* methods will correlate differently in gliomas and meningiomas because of the unique differences in morphologic and functional status of each tumor vascular network.METHODS: Before surgery, 27 patients with newly diagnosed gliomas (WHO grade I–IV; n = 20) or meningiomas (n = 7) underwent conventional anatomic MR imaging and 12 dynamic ssT1 acquisitions followed by 60 dynamic fpT2* images before and after gadopentate dimeglumine administration. The 3 hemodynamic variables—fpT2* rCBV, fpT2* Ktrans, and ssT1 Ktrans—were calculated in anatomically identical locations and correlated with glioma grade. The fpT2* Ktrans values were compared with ssT1 Ktrans for gliomas and meningiomas.RESULTS: All 3 hemodynamic variables displayed distinct distributions among grades 2, 3, and 4 gliomas by using the Kruskal-Wallis test. Only Ktrans values, and not rCBV, could differentiate between grade 4 and lower-grade gliomas by using the Wilcoxon rank sum test. The fpT2* Ktrans was highly predictive of ssT1 Ktrans for gliomas, with an estimated regression coefficient of 0.49 (P &lt; .001). For meningiomas, however, fpT2* Ktrans values correlated poorly with ssT1 Ktrans values (r = 0.26; P = .74).CONCLUSION: Compared with rCBV, Ktrans values derived from either ssT1 or fpT2* were more predictive of glioma grade. The fpT2* Ktrans was highly correlated with ssT1 Ktrans in gliomas but not in meningiomas.