title: Reproducibility of the brain perfusion index for measuring cerebral blood flow using technetium-99m compounds.
abstract: We previously developed an alternative method for estimating the brain perfusion index (BPI) using technetium-99m compounds and spectral analysis (SA) for quantification of cerebral blood flow (CBF). In this study, we investigated the reproducibility of the BPI values obtained by SA (BPIS) using a double injection of technetium-99m ethyl cysteinate dimer without any intervention, and compared it with that of the BPI values obtained by graphical analysis (BPIG). The BPIS values in the first (x) and second sessions (y) correlated closely (y=0.921x+0.036; r=0.962; n=64; s.e.e.=0.058 min-1). Although the BPIG values in the first (x) and second sessions (y) also correlated (y=0.942x+0.040; r=0.916; n=64; s.e.e.=0.061 min-1), the correlation coefficient for BPIS was significantly higher than that for BPIG. The reproducibility was dependent on the injection dose ratio of the second session to the first (R). The difference in BPI between the first and second sessions tended to be smaller when 1.5<R<2.5 than when 0<R<1.5 or 2.5<R. These results suggest that the reproducibility of BPIS is satisfactory and that it can be applied to two sequential measurements of CBF using a double injection of 99mTc compounds. When applying our method to such measurements, it is recommended that R is taken as approximately 2.0.
authors.affiliation: Department of Medical Engineering, Division of Allied Health Sciences, Osaka University Medical School, 1-7 Yamadaoka, Suita, Osaka 565-0871, Japan. murase@sahs.med.osaka-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Murase
authors.forename: H
authors.initials: H
authors.lastname: Fujioka
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: Y
authors.initials: Y
authors.lastname: Ishimaru
authors.forename: A
authors.initials: A
authors.lastname: Akamune
authors.forename: Y
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Mochizuki
authors.forename: J
authors.initials: J
authors.lastname: Ikezoe
mesh_terms: D000368:Aged; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003545:Cysteine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D008297:Male; D015609:Organotechnetium Compounds / Q000008:administration & dosage; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D015203:Reproducibility of Results; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine