Evaluation of Hamamatsu PET imaging modules for dedicated TOF-capable scanners

Area of Science:

• Medical Imaging
• Nuclear Physics
• Biomedical Engineering

Background:

• Time-of-flight (TOF) capability is increasingly vital in Positron Emission Tomography (PET) scanners.
• Proprietary electronics from vendors and researchers create challenges for independent TOF-PET system development.

Purpose of the Study:

• To assess the performance of a prototype TOF-PET scanner built with commercially available modules.
• To evaluate the feasibility of using Hamamatsu Photonics' TOF-capable modules as building blocks for PET scanners.

Main Methods:

• A prototype scanner with 16 Hamamatsu TOF modules (26.7 cm diameter) was constructed.
• Performance was evaluated using NEMA NU-4 "rat" phantom, measuring count rates, spatial resolution, energy resolution, sensitivity, and timing resolution.
• Measurements were conducted with energy windows from 350 to 700 keV.

Main Results:

• The scanner achieved a peak noise equivalent count rate (NECR) of 117.5 kHz at 75.25 MBq.
• Spatial resolution was 2.3 mm, energy resolution was 17.2% at 511 keV, and peak sensitivity was 1.28%.
• Excellent timing resolution of 462 ps was recorded.

Conclusions:

• The prototype scanner demonstrates the potential of commercially available TOF modules for constructing high-performance TOF-PET systems.
• These building blocks offer a viable pathway for independent research groups to develop advanced TOF-PET scanners.