First MR Electrical Properties Tomography reconstruction challenge: phase 3 - conductivity reconstructions from measured data

Motivation: To benchmark MR-Electrical Properties Tomography (MR-EPT) reconstruction methods. Goal(s): To present the results of phase 3 of the MR-EPT reconstruction challenge. Approach: MR measurements were performed for a cylindrical phantom, a 3D printed brain phantom, and a healthy volunteer. In each case, the transceive phase was measured using three different methods: bFFE, Spin-Echo, and Turbo Spin-Echo acquisitions. Results: 38 participants submitted conductivity reconstructions. Not all participants reconstructed conductivity maps for all three different transceive phase maps. The reconstructed conductivity maps show large variability in quality (visual scoring by experts), and performance (accuracy and precision). Impact: The results of phase 3 of the first MR-EPT reconstruction challenge show large variations in the estimated conductivity maps from measured data on phantoms and volunteer demonstrating the need of benchmarking reconstruction methods on common datasets.