Multicomponent measurements of radiation doses received by patients undergoing ct-examination with three type TLDs

About 20 % of the radiation dose during the radiological examinations is received from CT. The determination of the entrance surface dose is an important part of QA. Three types of TLD: LiF, CaSO4:Dy and α-Al2O3:C have been used after selection for homogeneity and reproducibility (SD<10 %) and calibration on the phantom surface. A large variation in the sensitivity in TLD responses from different luminescence materials is demonstrated. A good correlation coefficient (0,98) between CTDT and TLD-responses was observed. A space dose distribution profiles as well as the surface doses were determined for the center of the single scan and periphery in the gonad and thyroid gland positions (MU-Plovdiv). (author)