Background and Objective: Brain scans using computed tomography can help to visualize abnormalities and the internal details of organ structure. However, the use of X-rays may have an effect on the lens of eye, which is a radiosensitive tissue. The goal of this study was to measure the radiation dose at the lens of patient's eyes during a computed tomography examination.
Methods: An optically stimulated luminescence dosimeters (OSL) nanoDot detector was attached to both eyelids of patients who underwent 64 slices CT brain scanner (n=19) and 128 slices CT brain scanner (n=19) to measure the radiation dose of the patient's eye lens.
Results: The mean radiation doses to the left and right eye lenses from a 64 slices CT scanner were 31.964 mGy and 31.913 mGy, respectively. The mean radiation doses from a 128 slices CT scanner for the left and right eye lenses were 33.237 mGy and 32.929 mGy, respectively. It was found that the radiation doses to eye lens from both sides were not significantly different (p<0.01). The radiation dose does not exceed the minimum threshold for cataract formation (500 mGy) and the lens opacity (500 - 2000 mGy).
Conclusions: The mean radiation dose delivered to patients' eye lenses during 64-slice and 128-slice CT brain examinations does not exceed the minimum threshold for cataracts or lens opacity. The use of radiation shielding should not obscure the organ to be imaged.