Randomized Controlled Trial of Patient Positioning and Operator Radiation Exposure During Lower Extremity Catheter Angiography

Digital subtraction angiography (DSA) remains an important reference modality for evaluating chronic limb-threatening ischemia (CLTI), with left transradial access (TRA) increasingly favored for its lower complication rates and patient comfort. Radiation safety for operators is paramount, yet the impact of patient positioning on scatter radiation during lower limb diagnostic catheter angiography (CA) is understudied. This single-center randomized controlled trial evaluated whether head-first (HF) vs. feet-first (FF) supine patient orientation affects operator radiation exposure during lower extremity CA from left TRA. Between February and August 2024, 24 patients with CLTI were enrolled and randomized to HF or FF positions. Operator radiation exposure was measured using thermoluminescent dosimeters (TLDs) at the eye, chest, and left ring finger. Background radiation was subtracted. Procedures were standardized and performed by a single experienced interventional radiologist. Fluoroscopy time, dose area product (DAP), and contrast usage were recorded. No statistically significant differences were found between groups in patient BMI and procedural parameters. Patient positioning (HF vs. FF) did not significantly impact operator radiation exposure. A trend toward higher finger exposure in FF position suggests the need for optimized hand protection. These findings support flexible patient positioning without compromising operator safety, reinforcing adherence to ALARA principles.