Guillaume Madelin1, Alexej Jerschow2,
Ravinder R. Regatte1
1Radiology Department, New
York University Medical Center, New York, NY, United States; 2Chemistry
Department, New York University, New York, NY, United States
Sodium MRI is clinically interesting as it gives biochemical information non-invasively. The nucleus of the 23Na+ ion has a spin 3/2 with a quadrupolar moment that interacts with the surrounding electric field gradients and leads to biexponential T1 and T2. Multiple quantum filters can be used to discriminate between slow motion nuclei (intracellular) and fast motion (extracellular). Because of the sodium short T2, ultrashort TE sequences and high field systems are used to improve the signal-to-noise ratio and reduce the acquisition time. Biomedical applications are mainly: neurology (brain tumors, MS, Alzheimer's), MSK (cartilage, skeletal muscle), cardiac, body (breast, kidney, spine). Limitations of sodium MRI and perspectives are presented.