X-ray beam collimation in radiography: a study of compliance among radiographers

To assess collimation practices and quantify the irradiated area outside the area of diagnostic interest (ADI). 1503 radiographs (627 females and 876 males) of seven body regions for patients with (≤ 1-year, 1–12 years, 13–17 years, 18–65 years, ≥ 65-years) age groups from three major hospitals (A. governmental hospital, B. university affiliated hospital, and C. private hospital) in northern Jordan were included. For each radiograph, the length and width of the irradiated area and of the ADI were measured. Then the ratio factors (RF), the irradiated area outside ADI, and the percentage of irradiated area outside ADI were calculated. Kruskal-Wallis and Mann-Whitney-U tests were used to examine the differences in ADI, the irradiated area outside ADI and RF according to age and gender. A regression analysis identified variables associated with RF and irradiated area outside ADI and its percentage. The RF range from 1.7-3.5. Patients aged ≤ 1 year exhibited significantly higher irradiated area outside ADI (722.1 cm 2 ), RF (3.7), and the percentage of irradiated area outside the ADI (72.7%) compared to other age groups ( P <0.001). The actual collimation, area of ADI, and the irradiated area outside the ADI were significantly higher in males than those in females ( P <0.001). Hospital A had a significantly higher irradiated area outside the ADI (871.4 cm 2 ), RF (3.1), and percentage of irradiated area outside the ADI (67.2%) than other hospitals ( P <0.001) which can be due to high patient volume in governmental hospitals and less time to pay attention to patient protection. This study found inadequate X-ray beam collimation practice among radiographers in all participating hospitals, the radiation fields were at least two times larger than the ADI. This raises the importance of educating radiographers on collimation techniques and ensuring that all hospitals adhere to standardized collimation practices.