Investigation of spatial dose distributions for microscopic computed tomography

Understanding the spatial dose distributions using microscopic computed tomography (micro-CT) system is essential in investigating radiation doses received by small animals and by the working staff. The purpose of the present study is to investigate the spatial dose distributions of the Skyscan 1176 micro-CT system using thermoluminescent dosimeter TLD-100H. In this study, 180 TLD-100H chips and a Harshaw TLD readout system were used. TLD-100H chips were placed outside the scanning chamber and various positions of the instrument surface. The results showed that as the distance increase, the measured doses at the central axis of the scanning rotation decreased. The doses measured on the instrument surface are low (02.4-11.9μSv), and are close to the minimal detectable dose (1 μSv) of the TLD-100H. The mean measured dose at the control console was 5.4 μSv ± 2.84 μSv/month. In conclusion, the TLD-100H dosimeters are good candidates for dose monitoring in micro-CT study. Most of the scattered radiation of the Skyscan 1176 micro-CT can be attenuated by the shielding door and the doses received by the operator at the control console are acceptable.