Towards time-efficient sodium and proton MRI at 7T

Motivation: Sodium(²³Na) imaging may provide new assessments of neurological and physiological function, together with complimentary proton(¹H) MRI. However, current approaches lack efficient examination workflow. Goal(s): To develop a coil capable of both ¹H/²³Na imaging at 7T for improved workflow, with validated SAR, and high image quality. Approach: We designed a 16-channel ²³Na-loop/¹H-dipole array, validated safety through EM simulations and phantom experiments, and piloted in-vivo imaging compared to commercial alternatives. Results: Our array demonstrated comparable ²³Na image quality to a commercial coil, while enabling ¹H imaging with reduced RF power constraints. This pilot suggests simplified workflow for sequential ¹H/²³Na imaging without patient repositioning is possible. Impact: Pilot results demonstrate that integrated multichannel ²³Na/¹H transmit-receive RF coil design at 7T enables sufficient image quality without patient repositioning, streamlining workflow and reducing co-registration demands, paving the way for time-efficient multinuclear imaging in clinical applications.