Design of the RadFree randomized controlled study comparing LumiGuide, powered by Fiber Optic RealShape Technology, with conventional fluoroscopy guidance in fenestrated endovascular aortic repair

Objective: To evaluate whether the use of LumiGuide, a novel real-time three-dimensional navigation system powered by Fiber Optic RealShape technology (Philips), reduces procedure fluoroscopy time compared with conventional fluoroscopic guidance during fenestrated endovascular aortic repair (FEVAR). Methods: The RadFree study is a prospective, randomized, unblinded, multicenter clinical trial conducted at 11 vascular centers in Europe and the United States. Adults undergoing primary FEVAR with at least two target visceral vessels suitable for LumiGuide are randomized 1:1 to LumiGuide or conventional fluoroscopy. Stratification is performed by aneurysm extent. The primary endpoint is total procedure fluoroscopy time. Secondary outcomes include radiation exposure metrics (fluoroscopy time and rate, dose area product, and air kerma during navigation), cumulative procedural radiation dose, adverse LumiGuide device-related effects, and device deficiencies. Tertiary end points assess navigation efficiency and total procedure duration (first catheter/wire in to last catheter/wire out). The planned sample size of 182 subjects provides ≥80% power to detect a significant reduction in fluoroscopy time at a two-sided α of 0.05. Analyses follow an intention-to-treat approach. Results: This report details the trial rationale, methods, and planned analyses. Enrollment is currently ongoing; interim analysis will occur at 50% recruitment to assess safety and efficacy signals. Conclusions: RadFree is the first prospective, randomized multicenter trial evaluating the impact of LumiGuide on fluoroscopy time, radiation exposure and procedural efficiency in FEVAR. Its results will inform whether advanced three-dimensional navigation can safely and effectively reduce fluoroscopy dependence, improving safety for patients and endovascular teams.