The Dose Evaluation of Dental Computed Tomography in Meninges Area via CIRS phantom

• Main Authors: Hsu, Wei-Cheng, 徐暐程
• Other Authors: Cheng, Kai-Yuan
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/09166335760349479923

碩士 === 中臺科技大學 === 醫學影像暨放射科學系暨研究所 === 103 === Recently, dental computed tomography has become the important examination before dental implantations. This examination wasto simulate the implantation performed with an image guide system.Previous researches indicated that there are higher probability of meningiomas for patients underwent dental computed tomography. Therefore, this study used an anthropomorphic Rando phantom with TLDs and Gafchromic film to measure the absorbed dose of themeninges area in the brain. The data was analyzed to discuss the risk for meningioma resulting from the dental computed tomography examinations. The results showed 0.14mSv from TLD and 0.12mSv from film. Calculation was done based on ICRP 103 with nominal risk coefficient of 5.7%Sv-1, the risk of stochastic effect for patient undergoing dentalcomputed tomography were 0.0008% from TLD and 0.0007% from film. Based on the effective dose contribution obtained from both radiation detectors, estimated stochastic effect and radiation risk were relatively low. The effective dose contributions for meninges were only8% (Gafchromic film)and 7% (TLD). Therefore, it is concluded that the impact of dental computed tomography on the causing of meningiomas would be minimal.