A study of the dose to the thyroid and the eye in computed tomography of the brain

Thermoluminescent dosimeters were used to estimate the dose to the thyroid and the eye for routine clinical computed tomography of the brain using an EMI CT5005 scanner (20-sec data acquisition mode, bolus covering the head). The data can be summarized by the linear relations Dt = (7.5 +/- 0.8)N millirads (8 less than or equal to N less than or equal to 18) and De = (39 +/- 5)N + (1400 +/- 200)n millirads (8 less than or equal to N less than or equal to 20, 0 less than or equal to n less than or equal to 6) where Dt is the dose to the tissue anterior to the thyroid, De is the dose to the anterior tissue of the eyelid, N is the total number of CT cuts, and n is the number of cuts in which the globe of the eye is imaged.