RADIATION DOSE TO THE EYE AND POTENTIAL OCCURRENCE RADIATION- INDUCED CATARACT FOLLOWING COMPUTED TOMOGRAPHY (CT) HEAD EXAMINATION
The eye is a radiosensitive organ that lies within the scan range during Computed Tomography (CT) of the head. The utilization of the head CT is increasing with growing concern about the chances of development of cataract which induces by ionising radiation. This research aimed to calculate eye absorbed dose and to study the potential occurrence of radiation induces cataracts between CT Brain and CT Temporal. A total of 399 set data were obtained retrospectively according to inclusion and exclusion criteria. 364 patients underwent CT Brain while 35 patients’ data obtained for CT Temporal. The scanning parameters such as tube current, tube potential, pitch factor, beamwidth, filter, revolution time, and filter were recorded. Eye absorbed dose was significantly different (p<0.05) between CT brain (49.07±10.08mGy) and CT temporal (25.72 ± 6.12mGy). None of the analysed data exceeded the eye threshold dose recommended by ICRP 2012. However, as expected, the cumulative eye absorbed dose was increased as the frequencies of the scan increase. The highest number of repeated scans is five times with cumulative dose was recorded as 278.27mGy. In conclusion, the eye absorbed dose is higher in CT Brain compared to CT Temporal and has potential for induction of cataract in the future especially with the patient that undergoes repeated CT examination.
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