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
DO 10.3174/ajnr.A3012
A1 T.B. Nguyen
A1 G.O. Cron
A1 J.F. Mercier
A1 C. Foottit
A1 C.H. Torres
A1 S. Chakraborty
A1 J. Woulfe
A1 G.H. Jansen
A1 J.M. Caudrelier
A1 J. Sinclair
A1 M.J. Hogan
A1 R.E. Thornhill
A1 I.G. Cameron
YR 2012
UL http://www.ajnr.org/content/early/2012/03/22/ajnr.A3012.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 “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