How fast can we scan patients with modern (digital) PET/CT systems?

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Radiochemistry

Background:

• Positron Emission Tomography (PET) is crucial for cancer diagnosis and monitoring.
• Fast 18F-FDG PET imaging is desirable for patients experiencing discomfort or limited mobility.
• Optimizing acquisition time without compromising diagnostic accuracy is essential.

Purpose of the Study:

• To determine the minimal acquisition duration per bed position for digital PET systems.
• To evaluate if reduced scan times compromise image quality and lesion detection in 18F-FDG PET.
• To assess feasibility of accelerated PET imaging protocols.

Main Methods:

• 19 cancer and 9 pediatric patients underwent 18F-FDG PET scans on a Vereos digital PET system.
• List mode data were reconstructed with decreasing time frames down to 10 seconds per bed position.
• Image quality, noise levels, target-to-background ratios, and lesion detection were assessed by multiple readers.

Main Results:

• Reconstructions of 20, 30, and 60 seconds per bed position showed noise levels comparable to the standard 90-second acquisition.
• The 30-second acquisition demonstrated good inter-rater agreement for lesion and anatomical site detection (Kappa: 0.78-0.91).
• Total PET acquisition time was reduced from 12 minutes to 4 minutes with the 30-second protocol.

Conclusions:

• State-of-the-art digital PET systems enable fast imaging protocols.
• Acquisitions of 30 seconds per bed position are feasible with the Vereos system, maintaining diagnostic performance.
• Optimization of reconstruction parameters is key for successful accelerated PET imaging.