Normalized pediatric organ-absorbed doses from CT examinations.

Absorbed doses to the bone marrow, gonads, thyroid, eyes, breast, and skin from CT examinations of the head, chest, abdomen, and torso were measured in a phantom mimicking an average 6-year-old child. The doses were normalized to the CT dose index measured at the central position of a standardized cylindrical phantom, to allow approximation of organ-absorbed doses for similar scanners for which the CT dose index has been measured. Estimating organ-absorbed doses associated with CT examinations of children is necessary to evaluate the relative risks of carcinogenesis associated with radiation exposure of a particular organ. The risks from a particular CT examination depends on the patient's age because the geometric configuration of the organs (e.g., marrow distribution) changes over time and will, therefore, affect the scatter dose to the organs.