Reference dose levels for patients undergoing common diagnostic X-ray examinations in Irish hospitals.

Abstract

Wide variations in patient dose for the same type of X-ray examination have been evident from various international dose surveys. Reference dose levels provide a framework to reduce this variability and aid in the optimization of radiation protection. The aim of this study was to establish, for the first time, a baseline for national reference dose levels in Ireland for four of the most common X-ray examinations: chest, abdomen, pelvis and lumbar spine. Measurements of entrance surface dose using thermoluminescent dosemeters (TLDs) for these four X-ray examinations were performed on 10 patients in each of 16 randomly selected hospitals. This represented 42% of Irish hospitals applicable to this study. Results have shown wide variation of mean hospital doses, from a factor of 3 for an anteroposterior lumbar spine to a factor of 23 for the chest X-ray. The difference between maximum and minimum individual patient dose values varied up to a factor of 75. Reasons for these dose variations were complex but, in general, low tube potential, high mAs and low filtration were associated with high-dose hospitals. This study also demonstrated lower reference dose levels of up to 40% when compared with those established by the UK and the Commission of the European Communities for four out of six projections. Only the chest X-ray exhibited a similar reference level to those established elsewhere. This emphasizes the importance of each country establishing its own reference dose levels that are appropriate to their own radiographic techniques and practices in order to optimize patient protection.

The Need for Good Radiation Protection in Diagnostic Imaging in Ghana

“…Following increasing concern about radiation hazards from medical diagnostic x-ray, radiation dose assessment of patients undergoing medical diagnostic x-ray examinations has been suggested (Johnston and Brennan, 2000). This is because radiation dose assessment can reveal differences in patient dose and the cause of these variations.…”

Assessment of Entrance Skin Dose and Image Quality of Chest X-Rays in Two University Teaching Hospitals, North East Nigeria

“…X-ray is said to be the major contributor to the collective effective dose of the general public (personnel and patient). The need for radiation dose assessment of the patient during diagnostic x-ray examinations has been highlighted by increasing knowledge of hazard of ionizing radiation [ 3,5,20] . Because of the deleterious effects of x-rays, it is necessary to protect patients undergoing diagnostic and therapeutic procedures.…”

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