Accelerated echo-planar J-resolved spectroscopic imaging in the human brain using compressed sensing: a pilot...

Area of Science:

• Neuroimaging
• Metabolic Brain Imaging
• Magnetic Resonance Spectroscopy

Background:

• Obstructive sleep apnea (OSA) is linked to structural brain changes.
• Neurochemical alterations in OSA require detailed, multi-region brain measurements.
• Existing echo-planar J-resolved spectroscopic imaging (EP-JRESSI) is time-constrained for clinical use.

Purpose of the Study:

• To accelerate 4D EP-JRESSI using compressed sensing and nonuniform undersampling.
• To investigate metabolic changes in multiple brain regions of OSA patients.
• To compare neurochemical profiles of OSA patients with healthy controls.

Main Methods:

• Implemented nonuniform undersampling in spatial and spectral dimensions of 4D EP-JRESSI.
• Validated compressed sensing reconstruction reliability using a brain phantom.
• Scanned 9 OSA patients and 11 healthy controls using 3T MR imaging/MR spectroscopy.

Main Results:

• Observed significantly reduced metabolite levels in multiple brain regions of OSA patients versus controls.
• Key metabolites with altered levels include NAA/Cr, total Cho/Cr, Glx/Cr, taurine/Cr, and scyllo-Inositol/Cr.
• Differences were noted in the hippocampus, occipital gray matter, and frontal white matter.

Conclusions:

• Accelerated 4D EP-JRESSI with compressed sensing is feasible for clinical investigation of OSA.
• The study identified additional metabolite changes in OSA beyond those previously reported.
• This technique offers a faster approach to understanding neurochemical alterations in OSA.