Radiation doses to patients during barium examinations of the gastrointestinal tract

Abstract

Exposure to ionizing radiation is potentially , hazardous to living tissues, as reviewed in this study, such that patients undergoing x-ray examinations should be protected from excessive radiation dose. BetweenMayand November1990, a total of 405 patients mdergoing barium examinations, as requested by their Physicians, were rronitored at Kenyatta and Aga Khan hospitals in Nairobi using LiF dosemeters for radiation doses to the thyroid, skin and gonads. The characteristies of the patients and sorre technical factors of the examinations were studied too. It was found that 79. 8% of all barium examination patients in both hospitals were for Ba msal , 8.1% were for Ba swallow, and there was alrrost no patient below 29 years for Ba swallow. The-majority of the patients were in the 15-64 year age bracket, and there were IIDre female patients between 0-44 years at The AgaKhan (72.9%) than at Kenyatta (49. 7%t. While 2<143.6% of barium examination female patients were post-menopausal, 6.8%-7.6% had admittedly missed their periods or were over-due at the t.irre of examination. Peptic ulcer disease .accourrtedfor 54.3% to 61.0% of all indications for all barium examinations, and malignancy was an indication in 55. 6% to 59. 3% of all indications for Ba swallow.

The mean number of films per examination ranged frcm 2.4 to 7.3 and of radiographic exposures from 5. 4 to 12.6 with no evident interhospital difference. The rrean radiation dose to the thyroid amongadults ranged between 1 and 20 mGy at Kenyatta, and between 0.2,. and 20mGy at TheAgaKhan. PromBa rreal the interhospital ,dose difference was statisttcally significant (p<0.001) • The rrean radiation dose to the testes amongadults was between0.3 and 5 mGy(Kenyatta) and between Q.2 .and 8 mGy(TheAgaKhan). At Kenyatta during Ba rreal, the dose was highest amongchildren (5 mGy)and fell with age to be lowest amomg the elderly (2 rrGy). The interhospital dose difference amongadults during Ba rreal was highly statistically significant (p L..O.CXDl). The back skin surface doses were consistently higher, in both hospitals and from all examinations, than the ~ront surface doses or the mean of the four-site doses. The nean back surface skin doses from Ba rreal ranged from 551 mGyto 705 mGy(Kenyatta) and from 76mGy to 93 mGy (The Aga Khan), with a statistically significant interhospital difference ( pL 0.(01) in barium rreal doses. Ovary doses calculated from back skin doses ranged between 179 rrGy and 244 mGy, (Kenyatta, Ba meal.), .corrpared to between 25 mGyand 46 rmGy at TheAgaKhan.