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Abstract #0856

A Pilot Evaluation of Accelerated Echo-Planar J-Resolved Spectroscopic Imaging in the Human Brain Using Compressed Sensing

Manoj K. Sarma1, Rajakumar Nagarajan1, Jonathan Furuyama1, Jenny Li1, Paul M. Macey2, Rajesh Kumar3, M. Albert Thomas1

1Radiological Sciences, UCLA School of Medicine, Los Angeles, CA, United States; 2School of Nursing, UCLA School of Medicine, Los Angeles, CA, United States; 3Neurobiology, UCLA School of Medicine, Los Angeles, CA, United States

Compressed Sensing (CS) has revolutionized medical imaging with optimal encoding/reconstruction schemes for MRI and hyperpolarized MRSI. There have been no reports on combining 2 spectral dimensions with 2D or 3D spatial encoding applicable to human brain pathologies so far and the CS-based approaches are well-suited for MRSI combining 2 spectral and 2 spatial dimensions. We have evaluated a novel four dimensional (4D) echo-planar J-resolved spectroscopic imaging (EP-JRESI) sequence using non-uniform under-sampling (NUS) approaches for acceleration and CS for reconstruction in healthy human brain in vivo. The sequence has been implemented on a 3T MRI scanner equipped with a 12-channel head coil. Eight healthy volunteers and one patient with obstructive sleep apnea (OSA) have been evaluated. The 2D J-resolved spectra extracted from the CS-reconstructed 4D EP-JRESI data were processed using the prior-knowledge fitting (ProFit) algorithm to quantify cerebral metabolites in hippocampus and other locations.

Keywords

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