title: Regional indices of relative hepatic arterial perfusion from dynamic liver scintigraphy: the variability of indices and the use of parametric imaging.
abstract: Regional indices of relative arterial hepatic perfusion have been studied in 21 control subjects following dynamic radiocolloid scintigraphy of the liver (DLS). Three different indices have been calculated: the hepatic perfusion index (HPI); the hepatic arterial ratio (HAR) and the mesenteric fraction (MF). Three regions were defined in the upper, mid and lower right hepatic lobes and the three indices were calculated for each region. There was reasonable agreement between regional values of the same index with inter-regional correlation coefficients above 0.7 and standard errors in straight line fits of less than 0.093. There were significant regional differences for (1-MF) and HPI indices, but not for HAR. The index (1-MF) was calculated for each pixel and presented as a parametric image in 16 control subjects. The parametric images indicated the raised regional arterial indices due to overlying lung, right kidney and aorta. Parametric images may be of value to show the hepatic area free of significant overlying tissue and therefore available for analysis by DLS. However, the results suggest that the observed variability of single pixel indices limit the potential of parametric imaging for the localization of small focal lesions.
authors.affiliation: Department of Medical Physics, Southampton General Hospital, England, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Britten
authors.forename: J S
authors.initials: JS
authors.lastname: Fleming
authors.forename: A D
authors.initials: AD
authors.lastname: Flowerdew
authors.forename: I
authors.initials: I
authors.lastname: Taylor
authors.forename: S J
authors.initials: SJ
authors.lastname: Karran
authors.forename: D M
authors.initials: DM
authors.lastname: Ackery
mesh_terms: D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D008102:Liver Circulation; D011877:Radionuclide Imaging; D013671:Technetium Tc 99m Sulfur Colloid
chemical_list: D013671:Technetium Tc 99m Sulfur Colloid