[Quality control of dose calibrator using a traceable syringe-type (68)Ge/(68)Ga calibration source]

Area of Science:

• Nuclear medicine and instrumentation
• Radiopharmaceutical dosimetry
• Metrology in radioactivity

Context:

• Accurate calibration of dose calibrators (DCs) is essential for quantitative positron emission tomography (PET) studies.
• DC measurements are influenced by the radioactive nuclide and the measurement environment, necessitating site-specific calibration.
• A traceable Germanium-68/Gallium-68 (68Ge/68Ga) calibration source serves as a reliable surrogate for Fluorine-18 (18F).

Purpose:

• To determine optimal calibration values for dose calibrators (DCs) for measuring Fluorine-18 (18F) activity.
• To evaluate the performance of a DC using a traceable 68Ge/68Ga calibration source.
• To assess variations in sensitivity, geometry, and measurement uncertainty of DCs.

Summary:

• The study identified an optimal calibration number of 482 for the CRC-25PET, differing slightly from the manufacturer's recommendation of 480 for 18F.
• Over one year, the DC's sensitivity varied by less than 0.1%, with an expanded measurement uncertainty of 2.2%.
• The methodology adhered to the Guide for the expression of uncertainty in measurement (GUM) criteria for performance evaluation.

Impact:

• Ensures accuracy in quantitative PET imaging by providing precise activity measurements.
• Highlights the importance of regular, location-specific calibration of DCs using traceable sources.
• Contributes to the reliability and reproducibility of nuclear medicine procedures.