Repeatability of quantitative first-pass perfusion MRI in the mouse myocardium

Introduction Recently, first-pass perfusion MRI of the mouse myocardium was demonstrated. This technique is of considerable interest for the quantification of perfusion in preclinical models of cardiac disease. The repeatability of this method to quantify mouse myocardial perfusion has not been studied and still needs to be proven. Therefore, the main aim of this study was to evaluate the repeatability of quantitative, first-pass perfusion MRI in the healthy mouse heart. A dual-bolus approach was used for accurate determination of the arterial input function (AIF), while a Fermi constraint deconvolution model was used to quantify perfusion. First, we proved that the use of a pre-bolus allows for measuring an AIF that is not saturated, as would be the case for the second full bolus, by establishing linearity of AIF signal intensity with Gd-DTPA concentration. Secondly, repeatability of quantitative myocardial perfusion values was demonstrated by measuring a group of 9 mice at two time points.