The SNR-Optimal Sodium MRI Encoding

Motivation: Motivation is to unleash the clinical potential of sodium (23Na) MRI. Goal(s): Main goal is to answer the key question about what the optimal sequence encoding is?Approach: 3D sodium sampling schemes were designed, implemented and compared in simulations and experimentally in the human brain and porcine abdomen. Results: (1) While encoding schemes differ in sampling efficiency, 15ms-Density-Adapted Radial is SNR optimal. (2) Clinically reasonable acquisition parameters are: total scan time ~10min., nominal matrix size=803, readout duration=15ms, TR=30ms, flip angle=60°. Impact: Sodium MRI holds great clinical potential for diagnosing and monitoring of stroke, cancer, etc. Devising and comparing the optimal acquisition will help the sodium field to improve SNR, hence facilitating clinical studies and adoption.