Purpose: To determine the effectiveness of 0.5-mm-thick lead-equivalent aprons in vascular radiology.
Materials and methods: The radiation dose to radiology personnel was measured under and over lead aprons in more than 100 patient examinations. Thermoluminescent dosimeters of high and normal sensitivities (detection levels of 1 and 10 microGy, respectively) were used. Dose measurements in clinical practice were complemented with real-time measurement of generating potential, dose-area product, and fluoroscopy time. In addition, measurements of the radiation attenuation of aprons were performed in simulated exposure conditions. The generating potential in fluoroscopy--weighted for the contribution to the occupational exposure--varied between about 70 and 95 kV per examination (average, 78 kV).
Results: On the basis of measurements obtained under clinical conditions in vascular radiology, attenuation factors between 70 and 280 were derived. The typical radiation attenuation factor for 0.5-mm-thick lead-equivalent aprons was 200.
Conclusion: The effectiveness of 0.5-mm-thick lead-equivalent aprons, determined with clinical measurements, agrees with estimates based on generating potential. Previously published effective doses, inferred from nonclinically determined radiation transmission factors, probably overestimate the actual dose levels.