Assessing eye-lens doses of medical staffs in interventional radiology and cardiology procedures

• Main Authors: Liu, Yu-Rong, 劉育容
• Other Authors: Hsu, Fang-Yuh
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/56n5r5

碩士 === 國立清華大學 === 生醫工程與環境科學系 === 105 === The International Commission on Radiological Protection (ICRP) recommended that the equivalent dose limit for the lens of the eye be decreased from 150 mSv/y (ICRP, 2007) to 20 mSv/y averaged over five years (ICRP, 2011). How to accurately measure the eye-lens dose has, therefore, been an issue of interest recently. Interventional radiologists are at a higher risk of radiation-induced eye injury, such as cataracts, than all other occupational radiation workers. The main objective of this study is to investigate the relationship between the doses to the eye lenses of interventional radiologists measured by different commercial eye-lens dosimeters. This study measured a reference eye-lens dose, which involved placing thermoluminescent dosimeter (TLD) chips at the surface of the eye of the Rando Phantom, and the TLD chips were covered by a 3-mm-thick tissue-equivalent bolus. Commercial eye-lens dosimeters, such as a headband dosimeter and standard personnel dose badges, were placed at the positions recommended by the manufacturers. The results show that the personnel dose badge is not an appropriate dosimeter for evaluating eye-lens dose when it is worn on the chest inside a lead apron. Dose deviations for different dosimeters are discussed and presented in this study. Besides, the eye-lens dose measured by the headband dosimeter may estimate a higher dose to the eye lens than the dose measured by TLD-100H chips due to difference of physical TLD geometry and difference response in a low-energy photon filed. Therefore, the correction factor of energy dependence for TLD is important. Additionally, the issue of eye-lens dose accepted by interventional radiologists in Taiwan should be studied in the near future as their doses are already over the new dose limit.