The American College of Radiology Fluoroscopy Dose Index Registry: Initial Dosimetry Benchmark Results for Diagnostic Fluoroscopy Procedures
Abstract
Purpose
The ACR Fluoroscopy Dose Index Registry (DIR-FL) collected dose indices for diagnostic fluoroscopy procedures as part of a pilot program to expand the registry beyond interventional procedures. The data serve as the first insights by the DIR-FL into dosimetric performance in diagnostic fluoroscopy procedures in the US. The DIR-FL will provide the data needed to establish US DRLs and promote protocol optimization.
Methods
Diagnostic fluoroscopy procedure data from 7 health systems spread across 20 sites were collected over 3.5 years. Fluoroscopes capable of producing Radiation Dose Structured Reports and with both validated dose index accuracy and procedure mapping were included. Procedures were mapped by each institution to the appropriate ACR Common ID. Analyzed Common IDs were limited to those with a minimum of 75 exams and at least 5 contributing sites. Kerma Area Product (Pka) was analyzed as the primary dose index both to match most DRL literature and due to known problems with cumulative air kerma in non-interventional fluoroscopes. Other indices such as fluoroscopy time and number of radiographic images were also analyzed. Select procedures were further grouped into general categories to allow for broader comparisons.
Results
Over 43,000 exams across 14 procedures met the examination and site requirements and were analyzed. The most common examinations performed were modified barium swallows, upper gastrointestinal series, contrast enemas, and esophagrams with median (interquartile range) Pka values of 2.48 (1.32-4.33), 9.87 (4.08-18.55), 21.06 (12.53-33.33), and 7.82 (3.95-13.74) Gy-cm2 while fluoroscopy times were 2.23 (1.57-3.23), 1.82 (1.13-2.78), 1.83 (1.27-2.65), and 1.70 (1.03-2.72) minutes.
Conclusion
This study presents the first results of typical dose indices for diagnostic procedures in the ACR DIR-FL. Notably, the initial results for median Pka values appear higher than some European DRLs, which may be due to differences in patient populations or the need for further clinical optimization.