Combined prospective and retrospective motion correction for high-resolution linescan acquisitions in the human cerebral cortex at 7T

Motivation: Classical 1D linescan acquisitions have recently been shown to be valuable for recording in-vivo MRI signals across the layers of human cerebral cortex; however, these reduced-field-of-view techniques are vulnerable to rotational head movements as well as translations parallel and perpendicular to the line. Goal(s): To acquire high-quality, high-resolution linescan data that is robust to "in-line" and "through-line" motion. Approach: 3D-EPI volumetric navigators (vNavs) were incorporated into a spin-echo-based linescan pulse sequence. Results: We demonstrate that, by combining prospective and retrospective motion correction, we can acquire reliable linescan data with 0.5-mm readout resolution at 7T, in the presence of in-line and through-line head motion. Impact: Motion-robust linescan techniques will help enable the measurement of tissue microstructure and microvascular fMRI signals at high spatial resolutions, approaching the thickness of individual cortical layers, facilitating noninvasive studies of cortical circuitry and architectonics in the living human brain.