Fast, Robust T2 ‐ IVIM Quantitative MRI With Distortion and Motion‐Corrected Multi‐Echo EPI

ABSTRACT Purpose To enable robust, motion‐ and distortion‐corrected T2‐IVIM parameter estimation within clinically feasible scan times. Methods A single‐shot, multi‐echo spin‐echo EPI sequence was used to acquire abdominal diffusion‐weighted MRI with time‐efficient sampling of b‐value and TE pairs. The multi‐echo acquisition enabled distortion correction using reverse phase‐encoding between echoes. Motion and distortion correction were applied before fitting a joint T2‐IVIM model across the b‐value and TE dimensions to obtain TE‐independent IVIM parameters and compartment‐specific T2 estimates. For comparison, a previously established single‐echo T2‐IVIM protocol with longer scan times and a single‐echo protocol matched to the multi‐echo parameters were acquired. Uncertainty was evaluated with wild bootstrap error analysis. Results The multi‐echo approach enabled motion‐ and distortion‐corrected T2‐IVIM mapping in under 5 min, compared with 11–13 min for the prior minimal single‐echo protocol or nearly 19 min when acquired as separate shots. The liver was selected as the target organ due to its marked sensitivity to effects in standard IVIM. Error analysis showed comparable per‐voxel uncertainty between the multi‐echo method and the minimal single‐echo protocol. Conclusion The combination of multi‐echo sequence design and artifact correction enabled stable fitting of the extended T2‐IVIM model with improved liver coverage and less than half the scan time of prior protocols. These advances support broader clinical applicability of T2‐IVIM imaging by reducing acquisition burden while enhancing artifact correction and parameter robustness.