An extended bore length solid-state digital-BGO PET/CT system: design, preliminary experience, and performance...

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Positron Emission Tomography (PET)

Background:

• Advancements in PET/CT technology are crucial for improving diagnostic accuracy and patient outcomes.
• Solid-state detectors offer potential advantages in sensitivity and spatial resolution compared to traditional systems.

Purpose of the Study:

• To evaluate the performance characteristics of a novel solid-state PET/CT system utilizing Bismuth Germanium Oxide (BGO) scintillating crystals.
• To assess the system's capabilities over an extended 32 cm axial field-of-view (FOV) for high spatial resolution and sensitivity.

Main Methods:

• Performance was evaluated against NEMA NU 2-2018 and EARL Standards, including spatial resolution, scatter fraction (SF), noise equivalent count rate (NECR), and image quality (IQ).
• Bayesian penalized-likelihood reconstruction (BPL) was employed for IQ assessment, with EARL Standards 2 studies utilizing BPL and a deep learning algorithm.
• Patient scans with low-dose radiotracers ([18F]FDG, [68Ga]Ga-DOTA-TATE, [82Rb]RbCl) were acquired with total scan times of ≤ 8 minutes.

Main Results:

• The system achieved a NEMA sensitivity of 47.6 cps/kBq and spatial resolution ≤3.8 mm (OSEM).
• Peak NECR was 485.2 kcps, with SF at 35.6% and count rate accuracy of 2.16%.
• Good image quality was observed in patient scans, with EARL Standards 2 criteria met and Esser phantom features ≥4.8 mm resolved within 2 minutes per bed position.

Conclusions:

• The digital-BGO PET/CT system offers superior NEMA sensitivity and high count rates within its class.
• Its performance enables fast clinical acquisitions with reduced radiotracer doses, showcasing its clinical utility.