Fast High-Resolution T1 Mapping Using Inversion-Recovery Look-Locker Echo-Planar Imaging at Steady State: Optimization for Accuracy and Reliability

A fast T-1 measurement sequence using inversion recovery Look-Locker echo-planar imaging at steady state (IR LL-EPI SS) is presented. Delay time for a full magnetization recovery is not required in the sequence, saving acquisition time significantly for high-resolution T-1 mapping. Imaging parameters of the IR LL-EPI SS sequence were optimized to minimize the bias from the excitation pulses imperfection and to maximize the accuracy and reliability of T-1 measurements, which are critical for its applications. Compared with the conventional inversion recovery Look-Locker echo-planar imaging (IR LL-EPI) sequence, IR LL-EPI SS method preserves similar accuracy and reliability, while saving 20% in acquisition time. Optimized IR LL-EPI SS provided quantitative T-1 mapping with 1 x 1 x 4 mm(3) resolution and whole-brain coverage (28 slices) in approximately 4 min. Magn Reson Med 61:899-906, 2009. (C) 2009 Wiley-Liss, Inc.