High spatial resolution dual-ended readout PET detector based on continuous resistive layer silicon photomultiplier

Area of Science:

• Medical Imaging Physics
• Detector Technology
• Nuclear Medicine Instrumentation

Background:

• Positron Emission Tomography (PET) requires advanced detectors for improved spatial resolution.
• Continuous resistive layer position-sensitive silicon photomultipliers (CRL PS-SiPMs) are emerging photodetectors for fine-pitch scintillator arrays.
• Dual-ended readout architectures are being explored to enhance PET detector performance.

Purpose of the Study:

• To evaluate the performance of dual-ended readout PET detectors utilizing CRL PS-SiPMs.
• To assess the impact of temperature and bias voltage on detector characteristics.
• To determine the suitability of CRL PS-SiPMs for high spatial resolution PET applications with sub-millimeter pitch scintillators.

Main Methods:

• Constructed a dual-ended readout detector with CRL PS-SiPMs and a 0.5 mm pitch LYSO array (10x10 elements).
• Characterized detector performance (energy resolution, timing resolution, flood histogram quality) across varying bias voltages (30.0-33.0 V) and temperatures (3 °C, 14 °C, 24 °C).
• Evaluated depth-of-interaction (DOI) resolution at optimal operating conditions.

Main Results:

• Temperature had a minimal impact on detector performance.
• All LYSO crystals (0.44x0.44x20 mm³) were clearly resolved in flood histograms.
• Optimal performance at 24 °C and 32.5 V yielded average energy resolution of 22.7±3.4%, coincidence timing resolution of 1152±43 ps, and DOI resolution of 1.78±0.20 mm.

Conclusions:

• CRL PS-SiPMs are practical photodetectors for high spatial resolution PET scanners.
• The technology is well-suited for PET systems employing sub-millimeter pitch scintillator arrays.
• CRL PS-SiPMs demonstrate significant potential for DOI-capable PET detectors.