Robust measurement of T2 relaxation time in the developing fetal brain using ultrafast MOLED technique

Motivation: Unpredictable and intense motion poses serious challenges to quantitative imaging of the fetal brain. Goal(s): To evaluate the value of single-shot multiple overlapping-echo detachment acquisition (MOLED) imaging technique in accurately T2 mapping the developing fetal brain. Approach: Single-shot MOLED imaging was utilized for motion-robust T2 mapping in the developing fetal brain. The method was tested on phantom and in vivo, and a scan-rescan assessment was performed on nine fetuses. Results: MOLED T2 mapping strongly agreed with single-echo spin echo T2 (r = 0.996 in phantom). The median intra-subject coefficient of variation of T2 values between scan-rescan tests across the nine subjects is 1.385%. Impact: MOLED is a motion-robust, accurate, and repeatable method for T2 mapping of the whole developing fetal brain in only a few seconds. This method makes it feasible to use T2 maps to quantify early myelination in the fetal brain.