@article {Graham1157, author = {Michael M. Graham and Mark Muzi and Alexander M. Spence and Finbarr O{\textquoteright}Sullivan and Thomas K. Lewellen and Jeanne M. Link and Kenneth A. Krohn}, title = {The FDG Lumped Constant in Normal Human Brain}, volume = {43}, number = {9}, pages = {1157--1166}, year = {2002}, publisher = {Society of Nuclear Medicine}, abstract = {The lumped constant (LC) is a correction factor used to infer glucose metabolic rate (MRglc) from FDG metabolic rate (MRFDG). Methods: LC was determined in normal brain in 10 subjects (4 male, 6 female) by measuring regional MRglc and MRFDG independently using 1-11C-glucose and 18F-FDG with dynamic positron tomographic imaging, arterial blood sampling, and region-of-interest time-activity curve analysis with appropriate compartmental models. Results: The mean LC ({\textpm}SD) for normal brain was found to be 0.89 {\textpm} 0.08. The value for cerebellum was slightly lower, 0.78 {\textpm} 0.11 (P = 0.006; 2-tailed paired t test). Conclusion: The LC values determined in this study are considerably higher than older values in the literature, probably because of methodologic differences, but agree with a recent study by Hasselbalch.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/43/9/1157}, eprint = {https://jnm.snmjournals.org/content/43/9/1157.full.pdf}, journal = {Journal of Nuclear Medicine} }