%0 Journal Article
%A Zounek, Adrian Jun
%A Joerg, Nico Maximilian
%A Lindheimer, Felix
%A Zatcepin, Artem
%A Palumbo, Giovanna
%A Oos, Rosel
%A Delker, Astrid
%A Gildehaus, Franz Josef
%A Bollenbacher, Andreas
%A Boening, Guido
%A Bartenstein, Peter
%A Brendel, Matthias
%A Albert, Nathalie Lisa
%A Ziegler, Sibylle
%A Kaiser, Lena
%T 3D printing of radioactive wall-less PET phantoms improves threshold-based target delineation and quantification.
%J EJNMMI Physics
%V 12
%N 1
%@ 2197-7364
%C Heidelberg
%I SpringerOpen
%M DKFZ-2025-01171
%P 53
%D 2025
%X Validation of threshold-based PET segmentation and PET quantification is typically performed with fillable phantoms. Theoretical considerations show that the inactive walls of the phantom cavities introduce a contrast dependence of the volume-reproducing threshold (VRT), potentially leading to segmentation errors and therefore miscalculations of target volumes. The goal of this study was to experimentally show the contrast independence of the VRT when using wall-less phantoms.Radioactive spheres were produced according to NEMA specifications (D = 10/13/17/22/28/37 mm) using a stereolithographic (SLA) 3D printer. For comparison, hollow spheres were filled with a similar activity concentration. Image data from both sphere types were acquired with five different signal-to-background ratios (SBR = 2/4/6/8/10) using a Siemens mCT 20 and a Biograph 64 TruePoint PET/CT system. Results from wall-less and fillable spheres were compared to evaluate contrast dependence and segmentation accuracy based on VRT and intensity profiles. Wall-less phantoms demonstrated consistent VRT values, with a coefficient of variation of 2
%K 3D printing (Other)
%K PET (Other)
%K Phantoms (Other)
%K Segmentation (Other)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:40478365
%2 pmc:PMC12144006
%R 10.1186/s40658-025-00768-x
%U https://inrepo02.dkfz.de/record/301901