The American College of Radiology Fluoroscopy Dose Index Registry Pilot: Technical Considerations and Dosimetric Performance of the Interventional Fluoroscopes

Purpose: To characterize the accuracy and consistency of fluoroscope dose index reporting and report rates of occupational radiation safety hardware availability and use, trainee participation in procedures, and optional hardware availability at pilot sites for the American College of Radiology (ACR) Fluoroscopy Dose Index Registry (DIR). Materials and Methods: Nine institutions participated in the registry pilot, providing fluoroscopic technical and clinical practice data from 38 angiographic C-arm–type fluoroscopes. These data included measurements of the procedure table and mattress transmission factors and accuracy measurements of the reference-point air kerma (K_a,r) and air kerma–area product (P_KA). The accuracy of the radiation dose indices were analyzed for variation over time by 1-way analysis of variance (ANOVA). Sites also self-reported information on availability and use of radiation safety hardware, hardware configuration of fluoroscopes, and trainee participation in procedures. Results: All K_a,r and P_KA measurements were within the ±35% regulatory limit on accuracy. The mean absolute difference between correction factors for a given system in fluoroscopic and acquisition mode was 0.03 (95% confidence interval, 0.03–0.03). For the 28 fluoroscopic imaging planes that provided data for 3 time points, ANOVA yielded an F value of 0.134 with an F-critical value of 3.109 (P =.875). Conclusions: This publication provides the technical and clinical framework pertaining to the ACR Fluoroscopy DIR pilot and offers necessary context for future analysis of the clinical procedure radiation-dose data collected.