PET Detectors Based on Multi-Resolution SiPM Arrays.

Area of Science:

• Medical Imaging
• Detector Physics

Background:

• High spatial resolution positron emission tomography (PET) detectors face challenges in resolving edge crystals due to mismatched pitches between scintillator and photodetector arrays.
• This mismatch necessitates advanced solutions to maintain detector performance, particularly at the edges.

Purpose of the Study:

• To introduce and evaluate a novel multi-resolution silicon photomultiplier (SiPM) array design for PET detectors.
• The goal is to reduce the number of readout channels while preserving or enhancing edge crystal resolvability.

Main Methods:

• A pseudo 9 × 9 multi-resolution SiPM array (using various SiPM sizes) was designed and tested.
• Its performance was compared against a standard 8 × 8 SiPM array and a 16 × 16 SiPM array.
• A 36 × 36 LYSO scintillator array with a 1.5 mm pitch was used for evaluation.

Main Results:

• The multi-resolution SiPM array demonstrated edge crystal resolvability comparable to the 16 × 16 array.
• Performance significantly surpassed that of the 8 × 8 SiPM array.
• Digital grouping of smaller SiPMs effectively created larger pseudo-SiPMs for the array.

Conclusions:

• The proposed multi-resolution SiPM array design is a viable solution for improving edge crystal identification in PET detectors.
• It offers a method to decrease readout channels without compromising essential detector resolution.
• This approach holds promise for more efficient and effective PET detector development.