Radiation dose assessment to abdominal and pelvic organs in fluoroscopy-guided lumbar epidural steroid injections: A phantom-based analysis

This study aims to quantify organ-specific radiation doses during transforaminal lumbar epidural steroid injections (ESI) performed under C-arm fluoroscopic guidance using a phantom-based experimental setup. An Alderson Rando anthropomorphic phantom was used to simulate the human anatomy. A total of 32 MTS-100 thermoluminescent dosimeters (LiF:Mg,Ti) were placed at predefined anatomical sites representing abdominal and pelvic organs. Fluoroscopy was conducted using a Siemens Artis Zee system with standard clinical protocols at gantry angles of 0°, 45°, and 180°. The absorbed doses were measured, and organ-specific distributions were analysed. The highest radiation doses were recorded in the left kidney, pancreas, and spleen. Reproductive organs such as the upper ovaries and uterus also received moderate exposure, while the bladder and medulla spinalis received the lowest doses. It can be concluded that even the fluoroscopic beam is localized to the lumbar spine, scattered radiation can result in significant exposure to critical organs, which underlines the importance of optimized imaging protocols and targeted radiation protection measures.