Shortening the Duration of [18F]FDG PET Brain Examination for Diagnosis of Brain Glioma

Purpose Some patients cannot remain immobile for a long duration of 60 min, which is generally applied in the case of a 2-deoxy-2-[ 18 F]fluoro- d -glucose ([ 18 F]FDG) dynamic positron emission tomography (PET) scan. We investigated the change of the parametric values when the time duration of PET data was shortened. Procedures Eight normal subjects and four subjects with brain glioma were studied. The rate values of K 1 , k 2 , k 3 , and K i parametric images were computed by changing the time duration from 20 to 60 min, and changes of those parametric values were compared. Results The change was 20–30% and 3–5% for k 3 and K i , respectively, when the scan time was shortened from 60 to 40 min. The ratios of normal and disease regions in k 3 and K i values were similar, and contrasts of those images were not changed when the scan time was shortened to 40 min. Conclusions These results demonstrate that the short time duration of [ 18 F]FDG PET examination can provide an acceptable estimation of parametric k 3 and K i images.