Radiation dose evaluation in head and neck MDCT examinations with a 6-year-old child anthropomorphic phantom

CT examinations of the head and neck are the most commonly performed CT studies in children, raising concern about radiation dose and their risks to children.

The purpose of this study was to clarify radiation dose levels for children of 6 years of age undergoing head and neck multidetector CT (MDCT) examinations.

Radiation doses were measured with small-sized silicon-photodiode dosimeters that were implanted at various tissue and organ positions within a standard 6-year-old anthropomorphic phantom. Organ and effective doses of brain CT were evaluated for 19 protocols in nine hospitals on various (2-320 detector rows) MDCT scanners.

The maximum value of mean organ dose in brain CT was 34.3 mGy for brain. Maximum values of mean doses for the radiosensitive lens and thyroid were 32.7 mGy for lens in brain CT and 17.2 mGy for thyroid in neck CT. seventy-fifth percentile of effective dose distribution in brain CT was approximately the same as the diagnostic reference level (DRL) in the 2003 UK survey.

The results of this study would encourage revision of MDCT protocols in pediatric head and neck CT examinations for dose reduction and protocol standardization.