Performance Characteristics of a Dual-Sided Position-Sensitive Sparse-Sensor Detector for Gamma-ray Imaging

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Detector Physics

Background:

• Positron Emission Tomography (PET) systems require high-performance detectors for accurate imaging.
• Developing cost-effective PET detectors is crucial for wider clinical adoption and organ-specific applications.
• Sparse sensor arrays offer a potential solution for improving PET detector performance and reducing costs.

Purpose of the Study:

• To characterize the performance of a novel dual-sided position-sensitive sparse sensor (DS-PS3) array detector for PET.
• To evaluate the DS-PS3 detector's suitability for organ-specific imaging systems like brain and breast PET.
• To assess the cost-effectiveness and high-performance capabilities of the DS-PS3 detector design.

Main Methods:

• Utilized two sparse 4x4 arrays of silicon photomultipliers (SiPMs) with an 18.5% fill-factor.
• Employed a 15x15 array of 2-mm-pitch, 20-mm-long LSYO crystals coupled via a segmented light guide.
• Determined intrinsic spatial and depth-of-interaction (DOI) resolutions using a collimated gamma-ray source.

Main Results:

• Achieved an average intrinsic spatial resolution of 2.14 ± 0.07 mm FWHM.
• Measured DOI FWHM resolution ranging from 2.2 mm to 5.3 mm, with an average of 3.6 ± 0.8 mm.
• Obtained an average energy resolution of 16.6% for the detector module.

Conclusions:

• Demonstrated the feasibility of using dual-sided sparse sensor arrays for PET detectors.
• Showcased the DS-PS3 detector's ability to achieve low-cost, high-performance 3D positioning.
• Confirmed the potential of the 18.5% sensor fill-factor design for advanced PET imaging.