Room: Track 1
Purpose: To quantitatively assess the impact of non-leaded disposable shielding drapes on scattered-radiation exposure during fluoroscopically-guided interventional (FGI) procedures.
Methods: The ICRU/AAPM CT radiation dosimetry phantom (TG-200) was used to generate scattered-radiation similar to patient scatter during FGI procedures. The phantom was composed of 90 lbs. of polyethylene (30 cm diameter, 60 cm long), and imaged with a Philips Xpera c-arm unit with AEC. Images were acquired with techniques ranging 50-119 kVp and 14.3-16.7 mA. Performance of two commercial-available drapes containing bismuth and antimony, and manufactured to provide =90% attenuation at 90 kVp were assessed. Radiation exposure-rate was measured at three longitudinal locations (15, 30, and 45 cm) and seven angular positions (0°, ±30°, ±60°, and ±90°) about the central axis with a calibrated survey meter positioned 10 cm from phantom’s surface. Drapes were placed between the detector and phantom. Drapes were assessed in repeat observations by measuring the exposure-rate as a function of drape type and angular position, energy-dependent attenuation, and backscatter contribution. Analysis was done using paired-sample t-tests.
Results: Drapes A and B performed similarly (p=0.42) in reducing scatter exposure to the operator by 50% - 83% across all angular positions. For energy-dependent attenuation, drape A outperformed B across the entire energy spectrum assessed (p<0.05). The greatest dose reduction occurred 90° from the primary beam axis. For drapes A and B, respectively, backscatter was 53% and 98% higher compared to free-in-air measurement. Drapes positioned in the primary beam resulted in increased tube output by as much as 42%.
Conclusion: Our work demonstrates operator dose to the eyes, thyroid, and hands can potentially be reduced with drapes. Drapes may elevate backscattered radiation to patients, and may increase tube output if positioned in the primary beam. These results warrant further investigation of potential benefits and drawbacks of drapes.
Not Applicable / None Entered.