Although there have been many human medical reports of scattering dose and scattered radiation distributions in the computed tomography (CT) room, the investigations of specific scattering doses during veterinary CT imaging have not been reported. In this study, CT scattering doses in an examination room were measured during CT examinations in an animal hospital. Scattered radiation spatial mapping of the CT room from the routine acquisition settings that are used in actual clinical practice was performed for head, chest, abdomen, and pelvic measurements. Mapping measurements were carried out in four planes (50, 100, 150, and 200 cm above the floor) at a total of 260 locations. The largest scattering dose (133 μSv) was recorded on the bed at 50 cm caudal to the gantry center during pelvic measurements. In addition, the scattered radiation was greatest at a height of 100 cm from the floor and became progressively smaller over 150, 50, and 200 cm from the floor. The gantry side showed the smallest scattering dose. A 100-cm square of the gantry had a large scattering dose that became smaller as the distance from the bed increased. The effective dose experienced by the assistant who was using a protective apron was 3.9 μSv, which is in compliance with the ICRP recommendations for assistants who analyze less than 64 patients per year.
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