Speaker
Description
Recent developments in PET detectors have explored alternatives to conventional pixelated scintillator arrays in order to improve spatial resolution and DOI capabilities while maintaining good timing performance and reducing system cost. Among the different approaches proposed, semi-monolithic and pseudo-slab scintillation crystals aim to combine the advantages of pixelated and monolithic detectors by introducing controlled light sharing while preserving some degree of crystal segmentation. Moreover, BGO scintillators have regained popularity due to its lower cost, higher stopping power, higher photo-fraction and the lack of intrinsic radiation.
The main goal of this work is to compare the semi-monolithic and pseudo-slab designs using both LYSO and BGO scintillation crystals. In particular, four different configurations were tested: semi-monolithic blocks of 1×8 slabs (BGO and LYSO), a single LYSO pseudo slab, and an array of 1×8 BGO pseudo-slabs; all provided by Epic Crystals. The detectors were coupled to an 8×8 SiPM array (Hamamatsu S14) and readout using the TOFPET2 ASIC. A NN approach based on a MLP was implemented to estimate the interaction position along the monolithic and DOI direction. The models were trained with experimental data. The spatial resolution was evaluated from the error distributions of the predicted positions using the FWHM, MAE and Bias metrics.
The results show comparable DOI performance between pseudo-slab and semi-monolithic configurations, indicating that pseudo-slab detectors represent a viable alternative for PET systems requiring DOI capability. Ongoing work focuses on the analysis of the timing capabilities including the development of alternative electronic readout schemes to exploit the Cherenkov radiation of BGO crystals.
| Track | TBPET |
|---|---|
| Presentation type | Oral |