3D multiple overlapping-echo detachment (3D-MOLED) imaging for ultrafast simultaneous T2* and susceptibility mapping of whole-brain

Motivation: Current high-resolution T2* and susceptibility mapping techniques remain time-consuming or suffer from geometric distortion. Goal(s): Our goal was to achieve distortion-free and time-efficient quantification of whole-brain T2* and susceptibility. Approach: The multiple overlapping-echo detachment imaging (MOLED) method was extended to 3D acquisition for collecting more echoes for robust high-resolution parametric mapping. Single scan blip-up-down operation of two echo trains combined with deep learning reconstruction was used for distortion correction. Results: 3D-MOLED enables high-quality T2* and susceptibility mapping in 32 seconds, comparable to conventional 3D-GRE in 12 minutes, with Pearson’s correlation coefficient of 0.983 and 0.986, respectively. Impact: Distortion-free whole-brain T2* and susceptibility mapping at isotropic 1 mm3 resolution can now be achieved using our newly developed 3D-MOLED technique in only 32 seconds, which significantly improves the motion robustness of quantitative imaging in clinical examinations.