Dosimetric evaluation of a detailed eye model in head computed tomography examinations

3^rd International Conference on Medical Physics & Biomedical Engineering

November 07-08, 2016 Barcelona, Spain

Parisa Akhlaghi, Atiyeh Ebrahimi-Khankook and AlirezaVejdani-Noghreiyan

Tabriz University of Medical Sciences, Iran
University of Neyshabur, Iran

Posters & Accepted Abstracts: J Bioengineer & Biomedical Sci

Abstract :

Radiation exposure to the eye lens may occur within medical setting like head CT examination. Eye lens is sensitive to exposure by ionizing radiation mainly relating to the induction of cataract. ICRP publication, 118 recommended a threshold dose of 0.5 Gy for both acute and fractionated exposures for radiation-induced cataracts. As stated, cataract may be caused by the radiation injury to the germinative zone of the lens epithelium, which contains actively dividing cells. In the literature, eye was simply modeled containing lens and bulb and the cataract threshold was compared by the dose delivered to total lens. Recently, Nogueira et al., developed a detailed eye model, in which germinative zone was considered as the sensitive zone to ionizing radiation. Therefore, in this study, Nogueira eye model was developed and inserted in the head of ICRP reference adult male (AM) phantom, then dose values in head CT scan were calculated by Monte Carlo simulation and were compared with those obtained by AM simple eye model. The obtained results shows that despite the similarity of total lens dose in both models, the amount of dose delivered to the sensitive zone of the Nogueira model is higher than the lens dose of simple model up to 5%. So, if there is a small threshold for inducing cataract, considering the detailed eye model and using more accurate results of dose are beneficial to optimize patient�s radiation dose, to update the information about individual risk and to protect the lenses during head CT scan.

Biography :

Email: parissa_akhlaghi@yahoo.com