An Efficient Signal Averaging with Model-Based Reconstruction for Meso-scale Resolution T2*W GRE-EPI at 7T with High-Performance Gradients

Motivation: Achieving ultra-high resolution imaging using single-shot echo planar imaging (ssEPI) at 7T could enhance clinical T2*-weighted imaging by significantly reducing scan time. Goal(s): To improve image quality in ssEPI, addressing issues such as geometric distortion, Nyquist ghosting, and partial Fourier artifacts. Approach: A ssEPI-sequence was modified to enable dual readout and dual phase polarities, resulting in four different acquisitions. Joint reconstruction with integrated off-resonance correction was performed. Virtual coil locally low rank regularization was employed to handle partial Fourier effect. Results: The proposed method successfully reduced Nyquist ghosting and geometric distortions, achieving clearer, artifact-minimized images with fine structural details compared to conventional reconstructions. Impact: This advanced imaging technique enables rapid, ultra-high-resolution brain scans with reduced artifacts, enhancing structural detail and diagnostic quality. It provides a promising alternative to conventional methods, potentially advancing clinical neuroimaging and expanding applications of 7T MRI in research.