title: Evaluation of two population-based input functions for quantitative neurological FDG PET studies.
abstract: The conventional measurement of the regional cerebral metabolic rate of glucose (rCMRGlc) with fluorodeoxyglucose (FDG) and positron emission tomography (PET) requires arterial or arterialised-venous (a-v) blood sampling at frequent intervals to obtain the plasma input function (IF). We evaluated the accuracy of rCMR-Glc measurements using population-based IFs that were calibrated with two a-v blood samples. Population-based IFs were derived from: (1) the average of a-v IFs from 26 patients (Standard IF) and (2) a published model of FDG plasma concentration (Feng IF). Values for rCMRGlc calculated from the population-based IFs were compared with values obtained with IFs derived from frequent a-v blood sampling in 20 non-diabetic and six diabetic patients. Values for rCMRGlc calculated with the different IFs were highly correlated for both patient groups (r > or = 0.992) and root mean square residuals about the regression line were less than 0.24 mg/min/100 g. The Feng IF tended to underestimate high rCMRGlc. Both population-based IFs simplify the measurement of rCMRGlc with minimal loss in accuracy and require only two a-v blood samples for calibration. The reduced blood sampling requirements markedly reduce radiation exposure to the blood sampler.
authors.affiliation: PET Department, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Eberl
authors.forename: A R
authors.initials: AR
authors.lastname: Anayat
authors.forename: R R
authors.initials: RR
authors.lastname: Fulton
authors.forename: P K
authors.initials: PK
authors.lastname: Hooper
authors.forename: M J
authors.initials: MJ
authors.lastname: Fulham
mesh_terms: D000328:Adult; D001345:Autoradiography; D001800:Blood Specimen Collection; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002493:Central Nervous System Diseases / Q000097:blood / Q000000981:diagnostic imaging*; D003847:Deoxyglucose / Q000031:analogs & derivatives* / Q000097:blood; D003929:Diabetic Neuropathies / Q000097:blood / Q000000981:diagnostic imaging; D005069:Evaluation Studies as Topic; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D014055:Tomography, Emission-Computed / Q000379:methods*
chemical_list: D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose; D005947:Glucose