Towards genuine 3D DWI with physiological motion compensation: the feasibility on 3T with high performance gradients

Motivation: Direct 3D DWI can be implemented with second-order gradient moment nulling (M2) and cardiac synchronization. High performance gradients can alleviate the TE lengthening of M2. We intend to implement our 3D DWI sequence on a 3T scanner with high performance gradients. Goal(s): To investigate the feasibility of high resolution 3D DTI on 3T with high performance gradients. Approach: The sequence was implemented and 3D DTI scan were tested with 0.8 mm isotropic and 0.6 mm isotropic resolution. Results: 0.8 mm isotropic 3D DTI showed higher SNR than 2D SMS with identical scan time. 0.6 mm isotropic resolution 3D DTI scan was also feasible. Impact: Our results indicate that at ultra high spatial resolution, direct 3D DTI is superior to 2D SMS scan in terms of SNR. With high performance gradients, 3D DTI using M2 is more practical.