FIGURE 5.

Simulated 0.5 mm side voxel GRE signal fraction maps for the needle at an arbitrary 90, 30, 0 degree orientation. A,D, Needle shown as a baseline to compare the signal void. Maps without (B,E) and with (C,F) shims at a TE of 3 ms. Significant signal recovery predicted with shimming is visible in both planes parallel and orthogonal to the needle bevel. G,H, Profiles across the parallel and orthogonal slices for all conditions along the dotted lines in (A) and (D). Shimming recovers a large volume of the lost signal around the needle that is especially apparent in the orthogonal plane