Room: Exhibit Hall | Forum 8
Purpose: To determine lead equivalence (LE) of radiation protective apparatus in the cardiovascular angiography suite.
Methods: A commercially available lead foil, 3Mâ„¢ Lead Foil Tape 421, with nominal thickness of 0.1 mm was employed to graphically determine the LE of radiation protective apparatus with lead-equivalence specification of 0.125 mmPb (surgical cap), 0.25 mmPb (surgical drape), thyroid shield (0.5 mmPb) and lead eyeglasses (0.50 mmPb side shield and 0.75mmPb lens). The LE of protective apparatus were determined by utilizing the X-ray transmission curves obtained with the lead foil tape at 60, 70, 80, 90, 100, 110 and 120 kVp in combination with the spectral shaping filters of 0.1, 0.2, 0.3, 0.6, and 0.9 mmCu. The experimental setup-and-test method for transmission measurements in narrow beam geometry was conducted as spelled out in ASTM Designation F3094-14 standards. All measurements were performed using interventional angiography system under service mode for manual radiological parameters.
Results: The measured lead equivalence, at 80 kVp and 0 mmCu, of the lead protective eyeglasses, the side shield was 0.38 mmPb. On the other hand, the lens was 0.88 mmPb much higher than the “specified 0.75 mmPb�. For all apparatus investigated, the LE tends to be closer to the specified value at 80 kVp and 0 mmCu. At tube voltage higher than 90 kVp and higher spectral shaping filter thickness, the measured LE is higher than specified. At tube voltage lower than 70 kVp, the measured LE is lower than specified but increases with increasing spectral shaping filter thickness.
Conclusion: The traditional specification of LE without considering spectral shaping filter into account is still a valid measure. However, there is still a need to verify the LE of various protective apparatus when the needs arise. The influence of higher spectral shaping filter thickness unexpectedly resulted in higher lead equivalence thickness.
Not Applicable / None Entered.
Not Applicable / None Entered.