title: Beyond 18F-FDG: Characterization of PET/CT and PET/MR Scanners for a Comprehensive Set of Positron Emitters of Growing Application--18F, 11C, 89Zr, 124I, 68Ga, and 90Y.
abstract: This study aimed to investigate image quality for a comprehensive set of isotopes ((18)F, (11)C, (89)Zr, (124)I, (68)Ga, and (90)Y) on 2 clinical scanners: a PET/CT scanner and a PET/MR scanner.
  
  
  METHODS
  Image quality and spatial resolution were tested according to NU 2-2007 of the National Electrical Manufacturers Association. An image-quality phantom was used to measure contrast recovery, residual bias in a cold area, and background variability. Reconstruction methods available on the 2 scanners were compared, including point-spread-function correction for both scanners and time of flight for the PET/CT scanner. Spatial resolution was measured using point sources and filtered backprojection reconstruction.
  
  
  RESULTS
  With the exception of (90)Y, small differences were seen in the hot-sphere contrast recovery of the different isotopes. Cold-sphere contrast recovery was similar across isotopes for all reconstructions, with an improvement seen with time of flight on the PET/CT scanner. The lower-statistic (90)Y scans yielded substantially lower contrast recovery than the other isotopes. When isotopes were compared, there was no difference in measured spatial resolution except for PET/MR axial spatial resolution, which was significantly higher for (124)I and (68)Ga.
  
  
  CONCLUSIONS
  Overall, both scanners produced good images with (18)F, (11)C, (89)Zr, (124)I, (68)Ga, and (90)Y.
authors.affiliation: A*STAR-NUS Clinical Imaging Research Center, Singapore anna_therese@circ.a-star.edu.sg.
authors.forename: A Therese
authors.initials: AT
authors.lastname: Soderlund
authors.affiliation: A*STAR-NUS Clinical Imaging Research Center, Singapore.
authors.forename: Jasper
authors.initials: J
authors.lastname: Chaal
authors.affiliation: A*STAR-NUS Clinical Imaging Research Center, Singapore.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Tjio
authors.affiliation: A*STAR-NUS Clinical Imaging Research Center, Singapore.
authors.forename: John J
authors.initials: JJ
authors.lastname: Totman
authors.affiliation: Siemens Healthcare Molecular Imaging, Knoxville, Tennessee; and.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Conti
authors.affiliation: A*STAR-NUS Clinical Imaging Research Center, Singapore Department of Diagnostic Radiology, National University Hospital, Singapore.
authors.forename: David W
authors.initials: DW
authors.lastname: Townsend
mesh_terms: D002250:Carbon Radioisotopes / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry; D005462:Fluorine Radioisotopes / Q000737:chemistry; D019788:Fluorodeoxyglucose F18 / Q000737:chemistry*; D005710:Gallium Radioisotopes / Q000737:chemistry; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007457:Iodine Radioisotopes / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D064847:Multimodal Imaging / Q000379:methods*; D009369:Neoplasms / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000295:instrumentation* / Q000379:methods*; D011868:Radioisotopes / Q000737:chemistry; D019275:Radiopharmaceuticals / Q000737:chemistry; D014057:Tomography, X-Ray Computed / Q000379:methods*; D015021:Yttrium Radioisotopes / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
chemical_list: D002250:Carbon Radioisotopes; D003287:Contrast Media; D005462:Fluorine Radioisotopes; D005710:Gallium Radioisotopes; D007457:Iodine Radioisotopes; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes; D019788:Fluorodeoxyglucose F18; D015040:Zirconium
keywords: contrast recovery; image quality; positron emission tomography; radionuclide therapy; spatial resolution