title: Normal regional distribution of cerebral blood flow in dogs: comparison between (99m) Tc-ethylcysteinate dimer and (99m) Tc- hexamethylpropylene amine oxime single photon emission computed tomography.
abstract: Functional imaging provides important insights into canine brain pathologies such as behavioral problems. Two (99m) Tc-labeled single photon emission computed tomography (SPECT) cerebral blood flow tracers-ethylcysteinate dimer (ECD) and hexamethylpropylene amine oxime (HMPAO)-are commonly used in human medicine and have been used previously in dogs but intrasubject comparison of both tracers in dogs is lacking. Therefore, this study investigated whether regional distribution differences between both tracers occur in dogs as is reported in humans. Eight beagles underwent two SPECT examinations first with (99m) Tc-ECD and followed by (99m) Tc-HMPAO. SPECT scanning was performed with a triple head gamma camera equipped with ultrahigh resolution parallel hole collimators. Images were reconstructed using filtered backprojection with a Butterworth filter. Emission data were fitted to a template permitting semiquantification using predefined regions or volumes of interest (VOIs). For each VOI, perfusion indices were calculated by normalizing the regional counts per voxel to total brain counts per voxel. The obtained perfusion indices for each region for both tracers were compared with a paired Student's T-test. Significant (P < 0.05) regional differences were seen in the subcortical region and the cerebellum. Both tracers can be used to visualize regional cerebral blood flow in dogs, however, due to the observed regional differences, they are not entirely interchangeable.
authors.affiliation: Faculty of Veterinary Medicine, Department of Small Animal Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Antita
authors.initials: A
authors.lastname: Adriaens
authors.affiliation: Faculty of Veterinary Medicine, Department of Small Animal Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Ingeborgh
authors.initials: I
authors.lastname: Polis
authors.affiliation: Faculty of Veterinary Medicine, Department of Small Animal Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Tim
authors.initials: T
authors.lastname: Waelbers
authors.affiliation: Faculty of Veterinary Medicine, Department of Medical Imaging and Small Animal Orthopedics, Ghent University, Merelbeke, Belgium.
authors.forename: Eva
authors.initials: E
authors.lastname: Vandermeulen
authors.affiliation: Faculty of Veterinary Medicine, Department of Medical Imaging and Small Animal Orthopedics, Ghent University, Merelbeke, Belgium.|Department of Nuclear Medicine, Ghent University Hospital, Ghent, Belgium.
authors.forename: André
authors.initials: A
authors.lastname: Dobbeleir
authors.affiliation: Drug Quality & Registration (DruQuaR) group, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: De Spiegeleer
authors.affiliation: Faculty of Veterinary Medicine, Department of Medical Imaging and Small Animal Orthopedics, Ghent University, Merelbeke, Belgium.
authors.forename: Kathelijne
authors.initials: K
authors.lastname: Peremans
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000378:metabolism; D003545:Cysteine / Q000031:analogs & derivatives* / Q000378:metabolism; D004285:Dogs / Q000502:physiology*; D005260:Female; D015609:Organotechnetium Compounds / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000378:metabolism*; D019690:Technetium Tc 99m Exametazime / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods* / Q000662:veterinary
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; C059659:technetium Tc 99m bicisate; D003545:Cysteine
keywords: 99mTc-ECD; 99mTc-HMPAO; SPECT; cerebral blood flow; dogs