PhD public defence - Edilaine Honorio da Silva - Development of a practical eye lens dosemeter for interventional procedures in hospitals. - VUB
You are cordially invited to the Public defence of Edilaine Honorio da Silva to obtain the academic degree of ‘DOCTOR IN MEDICAL SCIENCES’.
Date: February 19, 2018 11:00 h
Auditorium Roger Van Geen, Lake House 11:00
Belgian Nuclear Research Center, Boeretang 201, 2400 Mol
Development of a practical eye lens dosemeter for interventional procedures in hospitals
During procedures, interventional cardiologists and radiologists can receive high occupational doses from complex scattered X-ray radiation fields. Recently, reports have raised the concern that a link exist between chronic exposure to these fields and effects in unshielded tissues such as the eyes and brain. In addition, a lower occupational dose limit to the lens of the eyes has been recommended in response to studies showing that cataracts can occur at threshold doses lower than previously assumed. Medical doctors can exceed this dose, due to their high workload, the complexity of the procedures performed and proximity to the radiation. Therefore, routine assessment of the eye lens dose and optimized protection, such as the use of lead glasses and lead caps, are now to be considered. The aim of this project was to develop an eye lens dosemeter suitable to be used together with lead glasses in the complex radiation field to which medical doctors are exposed. This was done by numerical and experimental methods. Firstly, a rod-shaped radiophotoluminescent dosemeter was characterized and re-designed to improve its angular response which makes it suitable for eye lens dosimetry, independently of the angle of the scatter radiation. Secondly, the influence of where the dosemeter is placed on lead protective glasses on determining the dose received by the eye lens was evaluated. This study showed that the optimal position for the dosemeter is over the lead glasses, close to its bridge over the nose. In a parallel study, the efficiency of several protective devices in reducing the dose received in the white matter and hippocampus of the brain was investigated. Our study demonstrated that suspended ceiling screens are the most effective and decrease the dose to the brain tissue by around 70%. Depending on their type, lead caps provide a protection from only 6% up to about 70%.
- (VUB) Nico Buls
- Filip Vanhavere