Rapid T1 mapping of mouse myocardium with saturation recovery Look-Locker method

Dynamic contrast-enhanced MRI using gadolinium or manganese provides unique characterization of myocardium and its pathology. In this study, an electrocardiography (ECG) triggered saturation recovery Look-Locker method was developed and validated for fast cardiac T(1) mapping in small animal models. By sampling the initial portion of the longitudinal magnetization recovery curve, high temporal resolution (∼ 3 min) can be achieved at a high spatial resolution (195 × 390 μm2) in mouse heart without the aid of parallel imaging or echo-planar imaging. Validation studies were performed both in vitro on a phantom and in vivo on C57BL/6 mice (n = 6). Our results showed a strong agreement between T(1) measured by saturation recovery Look-Locker and by the standard saturation recovery method in vitro or inversion recovery Look-Locker in vivo. The utility of saturation recovery Look-Locker in dynamic contrast-enhanced MRI studies was demonstrated in manganese-enhanced MRI experiments in mice. Our results suggest that saturation recovery Look-Locker can provide rapid and accurate cardiac T(1) mapping for studies using small animal models.