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, beam width, 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.
CT brain ; CT temporal ; cataract

Background: Nowadays, Computed Tomography (CT) plays an important role not only in diagnosis but also in evaluating the severity of cranial lesions, especially brain injuries. Objectives: (1) To determine the related factors of brain injury. (2) To identify the rate of discovering brain injuries in CT film. (3) To propose appropriate an time for performing CT examinations. Subjects and method: The retrospective study was carried out on 413 cranial traumatic cases admitted to Viet Tiep Hospital from 1/1/2006 to 31/12/2007. All of them were taken with a CT - scanner. Results: The percentage of male - patient is 4 times higher than this of female. Most of the patients were 21-30 year olds (69%). The most common cause was motor accidents (64%). The indirect (dislocation of middle line) and direct pathogenic images can be found in CT-scanner in 210/413 cases (50.85%) and 216/413 (52.30%), respectively. 114 cases (27.60%) underwent surgical treatments. 20 patients died (4.84%) because of severe and complex injuries. Conclusion: It is necessary to closely monitor all the changes of the signs and symptoms in order to specify CT-scanner examination on time.
related factor ; brain injury ; CT scanner