Mapping of Organ Radiation Dose Distribution in Abdominal X-ray Imaging Using Optically Stimulated Luminescent Dosimeters (OSLDs).

INTRODUCTION

X-ray imaging units often exhibit non-uniform radiation intensity across the imaging field, making accurate dose measurements challenging. This variability can impact patient safety and hinder the optimization of medical imaging procedures. Our study aims to map radiation doses in abdominal organs using optically stimulated luminescent dosimeters (OSLDs) to enhance dose accuracy and improve the quality of patient care in diagnostic imaging.

MATERIALS AND METHODS

A Kyoto Kagaku phantom (Kyoto, Japan) was placed supine on the table Bucky in a posteroanterior (PA) orientation, with a source-to-image receptor distance (SID) of 100 cm. Exposures were taken at three different kilovolt peak (kVp) settings (64.5, 70, and 75) with corresponding milliampere-seconds (mAs) values of 15, 20, and 25, respectively, using both anode- and cathode-oriented beams. Multiple nanoDot OSLDs (Landauer, Glenwood, IL, US) were positioned on the phantom's surface to measure the entrance surface dose (ESD) at anatomical locations corresponding to the liver, kidneys, and spleen.

RESULTS

ESD measurements revealed a non-uniform radiation distribution across abdominal organs. Organ doses increased with rising kVp and mAs, reflecting the influence of beam energy and exposure settings. With anode-facing beam orientation, liver doses ranged from 0.47 to 2.97 mGy, with higher values in central liver regions and right kidney segments. ESD to the spleen increased from 0.63 to 1.94 mGy. Under cathode-oriented conditions, liver doses ranged from 0.88 to 3.70 mGy, while kidneys and spleen received up to 3.41 and 2.96 mGy, respectively. The highest ESDs were recorded in liver segments 2, 3, 4A, 4B, 5, and 6 as well as in the central regions of the kidneys, underscoring the influence of anatomical positioning and X-ray beam orientation. Overall, cathode-facing beams delivered up to 50% higher liver doses and twice the spleen dose compared to anode-facing beams.

CONCLUSIONS

This study confirms that radiation intensity is non-uniformly distributed across abdominal regions during X-ray imaging, with significant implications for patient safety. It demonstrates that different organs receive varying radiation doses, enhancing our understanding of organ-specific exposure during diagnostic procedures. These findings underscore the importance of optimizing imaging protocols to minimize unnecessary radiation exposure, particularly to more sensitive organs, ultimately improving patient care in diagnostic radiography.