EFFECTIVE DOSE ESTIMATION IN WHOLE BODY 18F-FDG PET/CT IMAGING

Area of Science:

• Diagnostic radiation medicine
• Medical imaging
• Radiation protection

Background:

• Positron emission tomography-computed tomography (PET-CT) is a common functional imaging technique.
• Patient effective dose estimation is vital for radiation protection in PET-CT procedures.
• Multiple imaging sequences can significantly increase radiation exposure.

Purpose of the Study:

• To evaluate simple methods for estimating patient effective doses from PET-CT scans.
• To assess the impact of three static time-sequence imaging on total effective dose.
• To compare effective dose estimations using different dosimetry coefficients.

Main Methods:

• PET effective doses were calculated using Anderson et al. and Kaushik et al. coefficients.
• CT effective doses were measured using a CTDI phantom and ionization chamber.
• Dose was assessed for patients undergoing three static time-sequence PET-CT imaging.

Main Results:

• The CT dose was found to triple due to the three static time-sequence imaging.
• PET-CT effective doses ranged from 17.14 to 18.42 mSv using Kaushik et al. coefficients for a single low-dose CT scan.
• The study highlighted increased patient effective doses with multi-sequence imaging.

Conclusions:

• Simple estimation methods for PET-CT effective doses are feasible.
• Multiple static time-sequence imaging significantly increases patient radiation exposure.
• Accurate dose assessment is essential for optimizing radiation protection in PET-CT.