T2*-correction in dynamic contrast-enhanced MRI from double-echo acquisitions

Purpose To evaluate the importance of T-2*-effects on the arterial input function (AIF) and on the resulting dynamic parameter estimation in dynamic contrast-enhanced (DCE) MRI of high-grade gliomas. Materials and Methods Seven patients with high-grade gliomas were imaged in total 50 times using a double-echo DCE sequence. Kinetic analysis using the extended Tofts model was performed using AIFs with and without correction for T-2*-effects, and the resulting estimates of the transfer constant (K-trans), blood plasma volume (v(p)), and the rate constant (k(ep)) were compared. Numerical simulations were done for comparison with clinical results as well as to further investigate the dependency of parameter values on the magnitude of T-2*-induced errors. Results All kinetic parameters were found to be overestimated if T-2*-effects in the AIF were not accounted for; with v(p) being most severely affected. The relative error in each parameter was dependent on the absolute parameter magnitude, resulting in incorrect parametric tumor distributions in the presence of uncorrected AIF T-2*-effects. Conclusion In DCE, a sufficiently short echo time should be used or corrections for T-2*-effects based on double-echo acquisition should be made for correct quantification of kinetic parameters. J. Magn. Reson. Imaging 2014;39:1314-1319. (c) 2013 Wiley Periodicals, Inc.