Evaluation of X-ray Beam Collimation in Adult Chest Radiography

Restricting the irradiated volume can reduce X-ray scattering incidents on the image receptor. Proper X-ray collimation during medical imaging reduces a patient's dose while improving image quality. Even though the patient radiation dose due to chest X-ray imaging is low, the 'as low as reasonably achievable' (ALARA) principle should be satisfied, especially for young patients.

To evaluate the accuracy of collimation in digital chest radiography.

Ninety-eight chest radiographs were studied retrospectively from February 2021 to December 2021. Chest images were collected from three main centers in the Madinah region of Saudi Arabia. The ratio of the field of interest area to the field of view (FOV) was measured and calculated to determine the accuracy of X-ray beam collimation.

Out of 98 chest radiographs enrolled in the study, 87.8% (n=80) were adequately collimated, while 12.2% (n=18) were rejected due to inadequate collimation. The ratio of the field of interest collimated area of chest radiographs was 0.547, which indicated an acceptable value. Among the three centers, Center 2 showed higher, significant, adequate collimation than Center 1 (P<0.001) and Center 3 (P=0.007). There was a significant gender difference in collimation levels as the level of collimation of female chest radiographs is inferior to that of males (P>0.001).

The collimation of chest radiographs among the three centers was adequate. Based on the study findings, the X-ray beam collimation was sufficient, indicating good optimization and no unnecessary radiation exposure to patients and staff. The collimation of chest radiographs in females was significantly inferior to that of males.