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RT Journal Article
SR Electronic
T1 Diagnostic Accuracy of Dynamic Contrast-Enhanced MR Imaging Using a Phase-Derived Vascular Input Function in the Preoperative Grading of Gliomas
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1539
OP 1545
DO 10.3174/ajnr.A3012
VO 33
IS 8
A1 Nguyen, T.B.
A1 Cron, G.O.
A1 Mercier, J.F.
A1 Foottit, C.
A1 Torres, C.H.
A1 Chakraborty, S.
A1 Woulfe, J.
A1 Jansen, G.H.
A1 Caudrelier, J.M.
A1 Sinclair, J.
A1 Hogan, M.J.
A1 Thornhill, R.E.
A1 Cameron, I.G.
YR 2012
UL http://www.ajnr.org/content/33/8/1539.abstract
AB BACKGROUND AND PURPOSE: The accuracy of tumor plasma volume and Ktrans estimates obtained with DCE MR imaging may have inaccuracies introduced by a poor estimation of the VIF. In this study, we evaluated the diagnostic accuracy of a novel technique by using a phase-derived VIF and “bookend” T1 measurements in the preoperative grading of patients with suspected gliomas. MATERIALS AND METHODS: This prospective study included 46 patients with a new pathologically confirmed diagnosis of glioma. Both magnitude and phase images were acquired during DCE MR imaging for estimates of Ktrans_ϕ and Vp_ϕ (calculated from a phase-derived VIF and bookend T1 measurements) as well as Ktrans_SI and Vp_SI (calculated from a magnitude-derived VIF without T1 measurements). RESULTS: Median Ktrans_ϕ values were 0.0041 minutes−1 (95 CI, 0.00062–0.033), 0.031 minutes−1 (0.011–0.150), and 0.088 minutes−1 (0.069–0.110) for grade II, III, and IV gliomas, respectively (P ≤ .05 for each). Median Vp_ϕ values were 0.64 mL/100 g (0.06–1.40), 0.98 mL/100 g (0.34–2.20), and 2.16 mL/100 g (1.8–3.1) with P = .15 between grade II and III gliomas and P = .015 between grade III and IV gliomas. In differentiating low-grade from high-grade gliomas, AUCs for Ktrans_ϕ, Vp_ϕ, Ktrans_SI, and Vp_SI were 0.87 (0.73–1), 0.84 (0.69–0.98), 0.81 (0.59–1), and 0.84 (0.66–0.91). The differences between the AUCs were not statistically significant. CONCLUSIONS: Ktrans_ϕ and Vp_ϕ are parameters that can help in differentiating low-grade from high-grade gliomas. AUCarea under the receiver operating characteristic curveCT(t)tissue contrast concentration curve with timeCIconfidence intervalCVcoefficient of variationDCEdynamic contrast-enhancedKtrans_ϕvolume transfer coefficient obtained from phase-derived vascular input functionKtrans_SIvolume transfer coefficient obtained from magnitude-derived vascular input functionNPVnegative predictive valuePPVpositive predictive valueR1rate of longitudinal relaxationR2*observed rate of transverse relaxationROCreceiver operating characteristic analysisT1longitudinal relaxation timeVp_SIplasma volume obtained from magnitude-derived vascular input functionVIFvascular input functionVp_ϕplasma volume obtained from phase-derived vascular input function