Estimation of the Effective Dose of Cone Beam CT Using the CTDI Phantom

• Main Authors: Ho, Chang-Hung, 何常弘
• Other Authors: Chao, Max Min
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/18273474415557072327

碩士 === 中臺科技大學 === 醫學影像暨放射科學系暨研究所 === 103 === 　　CBCT is a new modality in dental radiology that has rapidly become popular. When selecting an appropriate examination technique for each patient, the ALARA principle should be followed. The purpose of study was evaluated three methods for calculating effective dose, CT dose index (CTDI), dose–area product (DAP) and TLD for a cone beam CT (CBCT) device. 　　CTDI100 measurements were performed in a CT head dose phantom with a pencil ion chamber. The DAP value was determined with a plane-parallel transmission ionization chamber connected to an electrometer. Organ dose measurements were performed using TLD dosimeters that were in the 19 most radiosensitive organs in the maxillofacial and neck area. 　　The results showed that the effective dose measured by using CDTI phantom and DAP was approached to the outcome of TLD. CTDI100 measurements: (43.51- 188.05 µSv ), DAP value: (55.06- 195.8µSv), TLD measurements: (68.3- 218.28µSv) . 　　The results reinforce need for constant review of protocols and rational use of new technologies.