Dose evaluation of the one-year-old child in PET imaging by¹⁸F-(DOPA, FDG, FLT, FET) and⁶⁸Ga-EDTA using reference...

Area of Science:

• Nuclear Medicine
• Medical Physics
• Radiological Dosimetry

Background:

• Pediatric organs are highly sensitive to radiation due to rapid growth.
• Accurate absorbed dose evaluation is vital to prevent long-term damage in children.
• Positron Emission Tomography (PET) uses radiopharmaceuticals that contribute to radiation exposure.

Observation:

• This study evaluated organ absorbed doses and whole-body effective doses for a one-year-old child using various PET radiopharmaceuticals.
• Simulations utilized one-year-old child reference voxel phantoms and GATE Monte Carlo methods.
• Results were compared against the International Commission on Radiological Protection (ICRP) Publication 128 (stylized phantom).

Findings:

• The highest absorbed doses were observed in the bladder wall (for 18F-DOPA, 18F-FET, 68Ga-EDTA), heart wall (for 18F-FDG), and liver (for 18F-FLT).
• Significant differences were noted in organ absorbed doses when comparing voxel phantom results with ICRP 128 stylized phantom data.
• Relative differences in effective dose estimates ranged from 8.6% to 22% compared to ICRP 128 values.

Implications:

• The use of detailed, age-specific voxel phantoms offers more precise estimations of organ absorbed doses and effective doses in pediatric patients.
• These findings underscore the importance of updated dosimetry models for pediatric nuclear medicine procedures.
• Improved pediatric dosimetry can lead to optimized radiation safety protocols and reduced risks in young patients undergoing PET imaging.