title: [Examination of optimal imaging start time as determined from neighboring organ accumulation on (99m)Tc-tetrofosmin adenosine stress myocardial SPECT].
abstract: For ATP stress (99m)Tc-Tetrofosmin myocardial perfusion images (MPI), SPECT imaging is normally started 60 minutes after tracer injection. When the same procedure is applied to Adenosine (Ado) stress MPI, the frequency of the mask-out procedure after reconstruction (MOP) is increased. In this study, we examined the optimal imaging time from accumulation and distribution of isotope to neighboring organs. Time-count curves from dynamic and planer images of the heart, liver, and left upper abdomen were generated in 7 patients for optimal imaging time. MOP was evaluated in ATP stress MPI, in which imaging started 60 minutes after tracer injection (ATP 60), Ado stress MPI with imaging 60 minutes after injection (Ado 60), and Ado stress MPI with imaging 30 minutes after injection (Ado 30), in 575 patients. Up to 30 minutes after injection, washout from the liver was rapid, but after 30 minutes, it was slow. Washout from the left upper abdomen was not constant. MOP was 12.1% ATP 60, 23.1% Ado 60, and 13.2% Ado 30. Changing from Ado 60 to Ado 30 significantly decreased MOP (p<0.05). On adenosine stress MPI, it shortened examination time and enabled SPECT imaging to start 30 minutes after tracer injection.
authors.affiliation: Department of Technical Radiology, Saitama Cardiovascular and Respiratory Center, Japan.
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Wakabayashi
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Morozumi
authors.forename: Masaki
authors.initials: M
authors.lastname: Shibasaki
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Matsuda
mesh_terms: D000241:Adenosine; D000368:Aged; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009943:Organophosphorus Compounds / Q000493:pharmacokinetics; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin; D000241:Adenosine