title: Effect of the duration of fasting on myocardial fluorine-18-fluorodeoxyglucose positron emission tomography images in normal males.
abstract: To evaluate the effect of the duration of fasting on myocardial fluorine-18-fluorodeoxyglucose (FDG) uptake and distribution, 16 FDG-positron emission tomography (PET) studies were performed in 7 normal volunteers under three different conditions: glucose loading, 6 h fasting and overnight fasting. In the glucose-loaded condition, all subjects had good image quality, and myocardial metabolic rates of glucose (MRGlc) were significantly higher than those in the other two conditions. In the 6 h and overnight fasting conditions, image qualities varied according to MRGlc. Although there were visually distinct regional differences with MRGlc ranging from 0.05 to 0.15 mumol/min per g, these differences were not impressive by a quantitative analysis. The ranges of MRGlc in these two fasted conditions overlapped each other. There was a significant negative linear correlation between MRGlc and serum free fatty acid levels. Thus, MRGlc and image quality in fasted normal subjects varied with the extent of the fed-to-starved transition under clinical fasting conditions (6 h to overnight), and this transition does not depend solely on the duration of fasting. These findings may explain the heterogeneity in FDG studies under fasting conditions.
authors.affiliation: Third Department of Internal Medicine, Chiba University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamanouchi
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Niwayama
authors.forename: K
authors.initials: K
authors.lastname: Nakagawa
authors.forename: S
authors.initials: S
authors.lastname: Aioi
authors.forename: N
authors.initials: N
authors.lastname: Shikama
authors.forename: T
authors.initials: T
authors.lastname: Himi
authors.forename: K
authors.initials: K
authors.lastname: Imazeki
authors.forename: Y
authors.initials: Y
authors.lastname: Itoh
authors.forename: Y
authors.initials: Y
authors.lastname: Masuda
mesh_terms: D000328:Adult; D003847:Deoxyglucose / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000378:metabolism; D005215:Fasting; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000008:administration & dosage; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D011859:Radiography; D014055:Tomography, Emission-Computed
chemical_list: D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose; D005947:Glucose