Swift Acetate Glial Assay (SAGA): An accelerated human 13C MRS brain exam for clinical diagnostic use

• Published in: Journal of magnetic resonance (1997) Vol. 207; no. 2; pp. 352 - 355
• Main Authors: Sailasuta, Napapon, Tran, Thao T., Harris, Kent C., Ross, B.D.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2010
• Subjects: Acetates - blood; Acetates - metabolism; Adult; Bicarbonate; Bicarbonates - metabolism; Brain; Brain Chemistry; Carbon Radioisotopes; Carbon-13 MRS; Creatine - metabolism; Female; Frontal Lobe - chemistry; Frontal Lobe - metabolism; Glial metabolism; Glucose - metabolism; Humans; Kinetics; Magnetic Resonance Spectroscopy; Male; Neuroglia - chemistry; Neuroglia - metabolism; Oxygen Consumption - physiology; Phosphocreatine - metabolism; Spectroscopy; Carbon-13 MRS; Spectroscopy; Brain; Bicarbonate; Glial metabolism
• ISSN: 1090-7807; 1096-0856
• DOI: 10.1016/j.jmr.2010.09.010

By infusing [1- 13C] acetate intravenously for 60 minutes before patient enters MR, glial metabolic rate was determined during 25.6 minute- 13C acquisition (SAGA, above). 13C MRS spectra (154-164ppm) acquired from frontal brain (inset) showing enrichment of bicarbonate compared to natural abundance total creatine (tCr) before (left) and after infusion of [1- 13C] acetate (lower, right), via metabolic pathway of glial TCA cycle indicated. [Display omitted] . ► 13C acetate MR spectroscopy defines glial metabolic rate for human brain. ► Low power 13C- noise decoupling metabolic rate determinations in frontal brain. ► Accelerated determination of human brain metabolism with 13C MRS in 25.6 min (SAGA). ► 13C acetate glial metabolic rate equivalent to measurements by conventional methods. We demonstrate a robust procedure for the quantitative characterization of glial metabolism in human brain. In the past, the slope of the uptake and production of enriched label at steady state were used to determine metabolic rates, requiring the patient to be in the magnet for 120–160 min. In the present method, 13C cerebral metabolite profiles were acquired at steady state alone on a routine clinical MR scanner in 25.6 min. Results obtained from the new short method (SAGA) were comparable to those achieved in a conventional, long method and effective for determination of glial metabolic rate in posterior-parietal and frontal brain regions.