  A novel method for fast and high-resolution metabolic imaging, called
ECcentric Circle ENcoding TRajectorIes for Compressed sensing (ECCENTRIC), has
been developed and implemented at 7 Tesla MRI. ECCENTRIC is a non-Cartesian
spatial-spectral encoding method optimized to accelerate magnetic resonance
spectroscopic imaging (MRSI) with high signal-to-noise at ultra-high field. The
approach provides flexible and random ($k,t$) sampling without temporal
interleaving to improve spatial response function and spectral quality.
ECCENTRIC needs low gradient amplitudes and slew-rates that reduces electrical,
mechanical and thermal stress of the scanner hardware, and is robust to timing
imperfection and eddy-current delays. Combined with a model-based low-rank
reconstruction, this approach enables simultaneous imaging of up to 14
metabolites over the whole-brain at 2-3mm isotropic resolution in 4-10 minutes.
In healthy volunteers ECCENTRIC demonstrated unprecedented spatial mapping of
fine structural details of human brain neurochemistry. This innovative tool
introduces a novel approach to neuroscience, providing new insights into the
exploration of brain activity and physiology.
