title: Optimization of yttrium-90 PET for simultaneous PET/MR imaging: A phantom study.
abstract: OBJECTIVE
  Positron emission tomography (PET) imaging of yttrium-90 in the liver post radioembolization has been shown useful for personalized dosimetry calculations and evaluation of extrahepatic deposition. The purpose of this study was to quantify the benefits of several MR-based data correction approaches offered by using a combined PET/MR system to improve Y-90 PET imaging. In particular, the feasibility of motion and partial volume corrections were investigated in a controlled phantom study.
  
  
  METHODS
  The ACR phantom was filled with an initial concentration of 8 GBq of Y-90 solution resulting in a contrast of 10:1 between the hot cylinders and the background. Y-90 PET motion correction through motion estimates from MR navigators was evaluated by using a custom-built motion stage that simulated realistic amplitudes of respiration-induced liver motion. Finally, the feasibility of an MR-based partial volume correction method was evaluated using a wavelet decomposition approach.
  
  
  RESULTS
  Motion resulted in a large (∼40%) loss of contrast recovery for the 8 mm cylinder in the phantom, but was corrected for after MR-based motion correction was applied. Partial volume correction improved contrast recovery by 13% for the 8 mm cylinder.
  
  
  CONCLUSIONS
  MR-based data correction improves Y-90 PET imaging on simultaneous PET/MR systems. Assessment of these methods must be studied further in the clinical setting.
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029 and Department of Biomedical Engineering, The City College of New York, New York, New York 10031.
authors.forename: Mootaz
authors.initials: M
authors.lastname: Eldib
authors.affiliation: Siemens Healthcare, New York, New York 10022.
authors.forename: Niels
authors.initials: N
authors.lastname: Oesingmann
authors.affiliation: Siemens Healthcare, New York, New York 10022.
authors.forename: David D
authors.initials: DD
authors.lastname: Faul
authors.affiliation: Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York 10029.
authors.forename: Lale
authors.initials: L
authors.lastname: Kostakoglu
authors.affiliation: Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York 10029.
authors.forename: Karin
authors.initials: K
authors.lastname: Knešaurek
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029; Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York 10029; and Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josée and Henry R. Kravis Cardiovascular Health Center, Icahn School of Medicine at Mount Sinai, New York, New York 10029.
authors.forename: Zahi A
authors.initials: ZA
authors.lastname: Fayad
mesh_terms: D009068:Movement; D064847:Multimodal Imaging / Q000295:instrumentation*; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D015021:Yttrium Radioisotopes
chemical_list: D015021:Yttrium Radioisotopes