Accelerated Echo Planer J-resolved Spectroscopic Imaging of Putamen and Thalamus in Obstructive Sleep Apnea.
Obstructive sleep apnea syndrome (OSAS) leads to neurocognitive and autonomic deficits that are partially mediated by thalamic and putamen pathology. We examined the underlying neurochemistry of those structures using compressed sensing-based 4D echo-planar J-resolved spectroscopic imaging (JRESI), and quantified values with prior knowledge fitting. Bilaterally increased thalamic mI/Cr, putamen Glx/Cr, and Glu/Cr, and bilaterally decreased thalamic and putamen tCho/Cr and GABA/Cr occurred in OSAS vs healthy subjects (p < 0.05). Increased right thalamic Glx/Cr, Glu/Cr, Gln/Cr, Asc/Cr, and decreased GPC/Cr and decreased left thalamic tNAA/Cr, NAA/Cr were detected. The right putamen showed increased mI/Cr and decreased tCho/Cr, and the left, decreased PE/Cr ratio. ROC curve analyses demonstrated 60-100% sensitivity and specificity for the metabolite ratios in differentiating OSAS vs.



Positive correlations were found between: left thalamus mI/Cr and baseline oxygen saturation (SaO2); right putamen tCho/Cr and apnea hypopnea index; right putamen GABA/Cr and baseline SaO2; left putamen PE/Cr and baseline SaO2; and left putamen NAA/Cr and SaO2 nadir (all p < 0.05). Negative correlations were found between left putamen PE/Cr and SaO2 nadir. These findings suggest underlying inflammation or glial activation, with greater alterations accompanying lower oxygen saturation. These metabolite levels may provide biomarkers for future neurochemical interventions by pharmacologic or other means.
Department of Radiological Sciences, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.
Manoj K
MK
Sarma
UCLA School of Nursing, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.|Brain Research Institute, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.
Paul M
PM
Macey
Department of Radiological Sciences, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.
Rajakumar
R
Nagarajan
Division of Pulmonary and Critical Care Medicine, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.
Ravi
R
Aysola
Brain Research Institute, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.|Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Ronald M
RM
Harper
Department of Radiological Sciences, UCLA Geffen School of Medicine, Los Angeles, CA 90095, USA.
M Albert
MA
Thomas
D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D002794:Choline / Q000378:metabolism; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D011699:Putamen / Q000000981:diagnostic imaging*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D020181:Sleep Apnea, Obstructive / Q000000981:diagnostic imaging*; D013053:Spectrophotometry; D013788:Thalamus / Q000000981:diagnostic imaging*
D015415:Biomarkers; D002794:Choline; D010100:Oxygen