Efficient method for calculating kinetic parameters using T1‐weighted dynamic contrast‐enhanced magnetic resonance imaging

It has become increasingly important to quantitatively estimate tissue physiological parameters such as perfusion, capillary permeability, and the volume of extravascular‐extracellular space (EES) using T1‐weighted dynamic contrast‐enhanced MRI (DCE‐MRI). A linear equation was derived by integrating the differential equation describing the kinetic behavior of contrast agent (CA) in tissue, from which K1 (rate constant for the transfer of CA from plasma to EES), k2 (rate constant for the transfer from EES to plasma), and Vp (plasma volume) can be easily obtained by the linear least‐squares (LLSQ) method. The usefulness of this method was investigated by means of computer simulations, in comparison with the nonlinear least‐squares (NLSQ) method. The new method calculated the above parameters faster than the NLSQ method by a factor of approximately 6, and estimated them more accurately than the NLSQ method at a signal‐to‐noise ratio (SNR) of < ∼10. This method will be useful for generating functional images of K1, k2, and Vp from DCE‐MRI data. Magn Reson Med 51:858–862, 2004. © 2004 Wiley‐Liss, Inc.