Figure 4.
QSM algorithms were optimized to minimize error metrics in this challenge. This figure shows results of the GRAZ TGV algorithm with varying regularization parameter α0. While the QSM image with α0 = 0.004 (right) suffered from over-smoothing and conspicuity loss in fine features such as vessels and the cortex, the RMSE was better than for the normally utilized α0 = 0.0005 (left). QSM images are scaled from −0.1 to 0.25 ppm.