TY - JOUR 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. DO - 10.3174/ajnr.A3012 AU - T.B. Nguyen AU - G.O. Cron AU - J.F. Mercier AU - C. Foottit AU - C.H. Torres AU - S. Chakraborty AU - J. Woulfe AU - G.H. Jansen AU - J.M. Caudrelier AU - J. Sinclair AU - M.J. Hogan AU - R.E. Thornhill AU - I.G. Cameron Y1 - 2012/03/22 UR - http://www.ajnr.org/content/early/2012/03/22/ajnr.A3012.abstract N2 - 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 “book-end” 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. Abbreviations 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 ER -