title: Everyman's prostate phantom: kiwi-fruit substitute for human prostates at magnetic resonance imaging, diffusion-weighted imaging and magnetic resonance spectroscopy.
abstract: OBJECTIVE
  To apply an easy-to-assemble phantom substitute for human prostates in T2-weighted magnetic resonance imaging (T2WI), diffusion-weighted imaging (DWI) and 3D magnetic resonance spectroscopy (MRS).
  
  
  METHODS
  Kiwi fruit were fixed with gel hot and cold compress packs on two plastic nursery pots, separated by a plastic plate, and submerged in tap water inside a 1-L open-spout plastic watering can for T2WI (TR/TE 7500/101 ms), DWI (5500/61 ms, ADC b50-800 s/mm2map) and MRS (940/145 ms) at 3.0 T, with phased array surface coils. One green kiwi fruit was additionally examined with an endorectal coil. Retrospective comparison with benign peripheral zone (PZ) and transitional zone (TZ) of prostate (n = 5), Gleason 6-7a prostate cancer (n = 8) and Gleason 7b-9 prostate cancer (n = 7) validated the phantom.
  
  
  RESULTS
  Mean contrast between central placenta (CP) and outer pericarp (OP, 0.346-0.349) or peripheral placenta (PP, 0.364-0.393) of kiwi fruit was similar to Gleason 7b-9 prostate cancer and PZ (0.308) in T2WI. ADC values of OP and PP (1.27 ± 0.07-1.37 ± 0.08 mm2/s × 10-3) resembled PZ and TZ (1.39 ± 0.17-1.60 ± 0.24 mm2/s × 10-3), while CP (0.91 ± 0.14-0.99 ± 0.10 mm2/s × 10-3) resembled Gleason 7b-9 prostate cancer (1.00 ± 0.25 mm2/s × 10-3). MR spectra showed peaks of citrate and myo-inositol in kiwi fruit, and citrate and "choline+creatine" in prostates. The phantom worked with an endorectal coil, too.
  
  
  CONCLUSIONS
  The kiwi fruit phantom reproducibly showed zones similar to PZ, TZ and cancer in human prostates in T2WI and DWI and two metabolite peaks in MRS and appears suitable to compare different MR protocols, coil systems and scanners.
  
  
  CONCLUSIONS
  • Kiwi fruit appear suitable as phantoms for human prostate in MR examinations. • Kiwi fruit show zonal anatomy like human prostates in T2-weighted MRI and DWI. • MR spectroscopy reliably shows peaks in kiwi fruit (citrate/inositol) and human prostates (citrate/choline+creatine). • The kiwi fruit phantom works both with and without an endorectal coil. • EU regulation No. 543/2011 specifies physical and biochemical properties of kiwi fruit.
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Ziemssenstrasse 1, D-80336, Muenchen, Germany. Ullrich.Mueller-Lisse@med.uni-muenchen.de.
authors.forename: Ullrich G
authors.initials: UG
authors.lastname: Mueller-Lisse
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Ziemssenstrasse 1, D-80336, Muenchen, Germany.
authors.forename: Sophie
authors.initials: S
authors.lastname: Murer
authors.affiliation: Department of Urology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Muenchen, Germany.|Department of Urology, Interdisciplinary Oncology Centre Munich (IOZ), Munich, Germany.
authors.forename: Ulrike L
authors.initials: UL
authors.lastname: Mueller-Lisse
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Ziemssenstrasse 1, D-80336, Muenchen, Germany.
authors.forename: Marissa
authors.initials: M
authors.lastname: Kuhn
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Ziemssenstrasse 1, D-80336, Muenchen, Germany.|Radiology Centre Munich (RZM), München, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Scheidler
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Munich ("Ludwig-Maximilians-Universität", LMU), Ziemssenstrasse 1, D-80336, Muenchen, Germany.|Department of Radiology, BG Unfallklinik Murnau, Murnau am Staffelsee, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Scherr
mesh_terms: D000368:Aged; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005638:Fruit; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D019047:Phantoms, Imaging; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D003401:Creatine; D002794:Choline
keywords: Diffusion-weighted imaging; Magnetic resonance imaging; Magnetic resonance spectroscopy; Phantom; Prostate cancer