PET/CT acquisition and processing protocols in the Netherlands.

Area of Science:

• Nuclear Medicine
• Radiology
• Medical Imaging

Background:

• Positron Emission Tomography/Computed Tomography (PET/CT) is crucial for diagnosing and staging various diseases.
• Standardization of acquisition and processing protocols is essential for consistent image quality and accurate patient management.
• Existing literature suggests potential variability in PET/CT protocols, but comprehensive data from a national cohort is limited.

Purpose of the Study:

• To assess the current variations in acquisition and processing protocols for four common PET/CT examinations in the Netherlands.
• To analyze differences in injected activity, scan duration, and their correlation with scanner sensitivity across Dutch hospitals.
• To quantify the impact of protocol variations on patient radiation dose.

Main Methods:

• A nationwide survey was conducted among all Dutch nuclear medicine departments with PET/CT scanners.
• Data on injected activity, acquisition times, and reconstruction/post-processing settings were collected for FDG-WB, [18F]F-PSMA, [68Ga]Ga-PSMA, and FDG-Brain PET/CT.
• Analysis included weight-dependent injected activity, acquisition count statistics, and correlations with scanner performance (NEMA sensitivity).

Main Results:

• Responses from 42 hospitals (58 PET/CT systems) revealed wide variations in injected activity and scan duration, even for identical scanner models and examination types.
• Scanner sensitivity showed a moderate negative correlation with the injected activity × scan duration product for FDG-WB and FDG-Brain, but less so for [18F]F-PSMA and not significantly for [68Ga]Ga-PSMA.
• Observed variations in injected activity resulted in patient radiation dose differences by factors of 4-5 for FDG-WB and FDG-Brain, and over 10 for PSMA tracers, persisting after accounting for other factors.

Conclusions:

• Significant inconsistencies in PET/CT imaging protocols exist across Dutch hospitals, leading to substantial variations in patient radiation doses.
• Protocol variations cannot be solely explained by differences in scanning or uptake times, indicating a need for further investigation into count statistics and processing settings.
• Standardization of PET/CT protocols is recommended to ensure consistent diagnostic accuracy and minimize unnecessary radiation exposure.