title: Mapping metabolic brain activation during human volitional swallowing: a positron emission tomography study using [18F]fluorodeoxyglucose.
abstract: We have previously shown that labelled water positron emission tomography (H2(15)O PET) can be used to identify regional cerebral blood flow (rCBF) changes in the human brain during volitional swallowing. (18F) fluorodeoxyglucose (FDG PET), by comparison, uses a glucose analogue to quantitatively measure regional cerebral glucose metabolism (rCMRglc) rather than rCBF. The main advantage of FDG PET is improved spatial resolution, and because of its pharmacodynamic properties, activation can be performed external to the scanner, allowing subjects to assume more physiologic positions. We therefore conducted a study of the brain's metabolic response while swallowing in the erect seated position, using FDG PET. Eight healthy male volunteers were studied with a randomised 2 scan paradigm of rest or water swallowing at 20-second intervals for 30 minutes. Data were analysed with SPM99 using multisubject conditions and covariates design. During swallowing, analysis identified increased rCMRglc (P<0.01) in the following areas: left sensorimotor cortex, cerebellum, thalamus, precuneus, anterior insula, left and right lateral postcentral gyrus, and left and right occipital cortex. Decreased rCMRglc were also seen in the right premotor cortex, right and left sensory and motor association cortices, left posterior insula and left cerebellum. Thus, FDG PET can be applied to measure the brain metabolic activity associated with volitional swallowing and has the advantage of normal task engagement. This has implications for future activation studies in patients, especially those suffering swallowing problems after brain injury.
authors.affiliation: Department of Gastrointestinal Science, University of Manchester, Hope Hospital, Manchester, UK. lou.harris@man.ac.uk
authors.forename: Mary Louise
authors.initials: ML
authors.lastname: Harris
authors.forename: Peter
authors.initials: P
authors.lastname: Julyan
authors.forename: Bhavna
authors.initials: B
authors.lastname: Kulkarni
authors.forename: David
authors.initials: D
authors.lastname: Gow
authors.forename: Anthony
authors.initials: A
authors.lastname: Hobson
authors.forename: David
authors.initials: D
authors.lastname: Hastings
authors.forename: Jamal
authors.initials: J
authors.lastname: Zweit
authors.forename: Shaheen
authors.initials: S
authors.lastname: Hamdy
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000502:physiology*; D001923:Brain Chemistry; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000000981:diagnostic imaging; D003627:Data Interpretation, Statistical; D003679:Deglutition / Q000502:physiology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose