A step toward diagnostic reference levels for male varicocele embolization: dosimetric comparison across two generations of angiographic systems

Purpose: Percutaneous endovascular embolization (PVE) of male varicocele is a widely adopted procedure performed in healthy young patients with long life expectancy. Dose-optimization systems are therefore essential to minimize procedural radiation risks. We aimed to investigate the effect of a recently implemented dose-reduction technology on dosimetric parameters and its potential implication in the definition of diagnostic reference levels (DRLs). Materials and Methods: A consecutive series of 113 patients (23.3 ± 9.1 yrs) submitted to PVE between January 2020 and December 2024 were retrospectively reviewed. Two groups based on the angiographic system used, 50 patients treated using the Philips Allura Xper FD20 and 63 patients using the newer Philips Azurion Clarity IQ technology, were compared in terms of demographic, procedural, and dosimetric data. Results: Despite similar fluoroscopy and procedure times, the recently implemented angiographic technology demonstrated a significant reduction in dose area product (DAP) and reference air kerma (Ka.ref) values (4394.5 vs 20,709 mGy·cm2 and 20.35 vs 83.6 mGy; p < 0.001, respectively) with a percentage reduction of approximately 71.15% and 64.41%, respectively. Subpopulation analyses showed significant dose reductions in younger patient population (< 18 years) and in high-grade varicoceles (grades III/IV), with similar fluoroscopy times. Conclusion: The use of advanced dose-optimization technologies, together with standardized protocols and appropriate operator training, leads to a significant reduction in radiation exposure during PVE, particularly in younger patients. These single-center, retrospective results provide preliminary data that may support the future introduction of procedure-specific DRLs for this routinely and widely performed interventional radiology procedure.