Image quality evaluation for a clinical organ-targeted PET camera

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Radiological Physics

Background:

• Positron Emission Tomography (PET) is crucial for cancer imaging.
• Organ-dedicated PET systems offer improved sensitivity and resolution.
• Evaluating new PET technologies is essential for clinical advancement.

Purpose of the Study:

• To assess the performance of the novel Radialis PET system.
• To evaluate imaging characteristics impacting quantitative accuracy and lesion detectability.
• To compare Radialis PET performance with existing systems.

Main Methods:

• Standardized and custom tests were used, including those for Positron Emission Mammography (PEM).
• Evaluated parameters included spatial resolution, uniformity, and recovery coefficients.
• Clinical images with varying 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (18F-FDG) activity and time delays were acquired.

Main Results:

• In-plane spatial resolution was 2.3 mm ± 0.1 mm; spatial accuracy was 0.1 mm.
• Uniformity measurements were 11.7% (flood field) and 8.3% (NEMA NU-4 phantom).
• Demonstrated improved contrast recovery and spill-over ratio compared to similar commercial PET systems.

Conclusions:

• Radialis PET accurately reconstructs activity in tumors as small as 5 mm.
• The system is suitable for image-guided assessment of treatment response in small lesions.
• Recovery coefficient is a key metric for accurate lesion assessment in PET imaging.