Rapid Microscopic 3D-Diffusion Tensor Imaging Fiber-Tracking of Mouse Brain in Vivo by Super Resolution Reconstruction: Validation on MAP6-KO Mouse Model

Exploring mouse brains by rapid 3D-Diffusion Tensor Imaging (3D-DTI) of high spatial resolution (HSR) is challenging in vivo. Here we use the super resolution reconstruction (SRR) postprocessing method to demonstrate its performance on Microtubule-Associated-Protein6 Knock-Out (MAP6-KO) mice. Two spin-echo DTI were acquired (9.4T, CryoProbe RF-coil): (i)-multislice 2D-DTI, (echo-planar integrating reversed-gradient) acquired in vivo in the three orthogonal orientations (360 μm slice-thickness, 120 × 120 μm in-plane resolution, 56 min scan duration); used in SRR software to reconstruct SRR 3D-DTI with HSR in slice-plane (120 × 120 × 120 µm) and (ii)-microscopic 3D-DTI (µ-3D-DTI), (100 × 100 × 100 µm; 8 h 6 min) on fixed-brains ex vivo, that were removed after paramagnetic contrast-agent injection to accelerate scan acquisition using short repetition-times without NMR-signal sensitivity loss. White-matter defects, quantified from both 3D-DTI fiber-tracking were found very similar. Indeed, as expected the fornix and cerebral-peduncle volume losses were − 39