Radiation biology for pediatric radiologists

Area of Science:

• Radiology and Radiation Oncology
• Medical Physics
• Public Health

Background:

• Radiation exposure poses risks including heritable effects, developmental issues in fetuses, and carcinogenesis.
• Carcinogenesis is the primary concern for low-dose radiation, with risk estimates derived from studies like the A-bomb survivors.
• Diagnostic radiation use has surged, increasing collective population dose significantly.

Purpose of the Study:

• To review the biological effects of radiation relevant to radiologists.
• To highlight the increasing population dose from diagnostic imaging, particularly CT scans.
• To emphasize the importance of the As Low As Reasonably Achievable (ALARA) principle in radiation protection.

Main Methods:

• Review of established knowledge on radiation biological effects.
• Analysis of trends in diagnostic radiation use and population dose.
• Discussion of risk estimates for heritable effects, fetal development, and cancer.

Main Results:

• Heritable effects risk is low (0.2%/Sv).
• Fetal exposure during 8-15 weeks carries high mental retardation risk (40%/Sv) with a likely threshold.
• Carcinogenesis risk is estimated at 5%/Sv, making it the main concern.
• Annual collective population dose increased 750% since 1980, driven by CT scans.
• Pediatric CT scans contribute significantly to lifetime mortality risk.

Conclusions:

• Carcinogenesis is the most significant risk from diagnostic radiation.
• The rise in CT scans, especially in children, presents a growing public health concern.
• Adherence to the ALARA principle is crucial for minimizing radiation risks, particularly in pediatric imaging.