title: Influence of time delay on the estimated lung shunt fraction on 99mTc-labeled MAA scintigraphy for 90Y microsphere treatment planning.
abstract: 90Y-microspheres therapy is used to treat selected patients with primary or metastatic liver tumors in a safe and effective way. As a preparation for 90Y-microspheres treatment, a 99mTc-macroaggregated albumin (99mTc-MAA) simulation procedure is essential to evaluate particle shunting to the lung or gastrointestinal tract. We investigated the effect of interval between injection of 99mTc-MAA and time of scanning on the lung shunt fraction (LSF). In 4 patients with secondary hepatic malignancies who underwent repeated whole-body scintigraphy up to 5 hours after injection of 99mTc-MAA, a marked change in LSF was observed. It appears that tracer degradation leads to an important overestimation of LSF at later time points. An overestimation of LSF can lead to dose reduction or canceling of the planned 90Y-microspheres treatment. It is concluded that the interval between injection and scanning should be kept as short as possible.
authors.affiliation: From the Departments of *Nuclear Medicine; †Radiology; ‡Digestive Oncology; §Radiation Oncology; and ∥Laboratory for Radiopharmacy, University Hospitals Leuven and KU Leuven, Leuven, Belgium.
authors.forename: Ruth
authors.initials: R
authors.lastname: De Gersem
authors.forename: Geert
authors.initials: G
authors.lastname: Maleux
authors.forename: Hubert
authors.initials: H
authors.lastname: Vanbilloen
authors.forename: Kristof
authors.initials: K
authors.lastname: Baete
authors.forename: Chris
authors.initials: C
authors.lastname: Verslype
authors.forename: Karin
authors.initials: K
authors.lastname: Haustermans
authors.forename: Alfons
authors.initials: A
authors.lastname: Verbruggen
authors.forename: Eric
authors.initials: E
authors.lastname: Van Cutsem
authors.forename: Christophe Michel
authors.initials: CM
authors.lastname: Deroose
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007267:Injections; D008168:Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D011877:Radionuclide Imaging; D011880:Radiotherapy Planning, Computer-Assisted; D013668:Technetium Tc 99m Aggregated Albumin; D013997:Time Factors; D014692:Ventilation-Perfusion Ratio; D015021:Yttrium Radioisotopes / Q000737:chemistry / Q000627:therapeutic use
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin; D015021:Yttrium Radioisotopes