2026-10-12T18:26:49Z https://www.scidb.cn/oai

10.57760/sciencedb.0129b 2026-09-11T10:30:42Z

2026-09-11 Towards the Limits of Spatial Resolution in Preclinical PET: Prototype Validation and High-Sensitivity Dual-Layer Extension doi:10.57760/sciencedb.0129b en High spatial resolution and sensitivity are paramount in preclinical positron emission tomography (PET). Thicker scintillators improve detection efficiency but increase depth-of-interaction (DOI) parallax, whereas thinner scintillators reduce depth uncertainty at the expense of sensitivity. We developed and experimentally evaluated a compact PET scanner utilizing 0.579-mm-pitch, 5-mm-thick lutetium yttrium orthosilicate (LYSO) crystal arrays (0.497 × 0.497 × 5 mm3) and investigated a higher-sensitivity dual-layer architecture with discrete DOI encoding through simulation. The prototype achieved an energy resolution (full width at half maximum, FWHM) of 13.43% ± 1.95% at 511 keV, a peak sensitivity of 0.87% (350–650 keV window), a peak noise-equivalent count rate of 6.02 kcps, and a scatter fraction of 8.92%. Filtered back-projection yielded mean radial, tangential, and axial spatial resolutions (FWHM) of 0.90, 0.86, and 0.69 mm, respectively, reaching a minimum axial FWHM of 0.48 mm. Micro-Derenzo phantom imaging demonstrated sub-0.5-mm contrast modulation, with mean peak-to-valley ratios of 1.65 and 1.48 for the 0.45- and 0.40-mm rod sectors. In 18F-NaF murine imaging, the computed tomography (CT)-referenced structural similarity index was 0.79, versus 0.67 for a commercial scanner. Three configurations retained the prototype as the inner-layer detector ring, adding outer crystals with thicknesses of 5, 7.5, or 10 mm, and expanded axial coverage. Simulated peak sensitivity increased monotonically to 3.10%, 4.27%, and 5.36% (up to a 4.36× gain over the baseline), while spatial resolution degradation remained constrained due to a high fraction (71.1%–85.7%) of coincidences retaining inner-layer interaction endpoints. These results validate the prototype’s state-of-the-art spatial resolution and establish a viable architectural blueprint for next-generation DOI-PET systems. Positron emission tomography; high-resolution imaging; depth-of-interaction; instrumentation Chenxi Li Leran Wang Haoqi Wen Yuhao Jiang Runze Liao Yaping Luo Boxuan Shi Jianyong Jiang PUBLIC https://creativecommons.org/licenses/by/4.0/ dataset Science Data Bank