Data and methods to assess occupational exposure to personnel involved in cardiac catheterization procedures.

ABSTRACT

PURPOSE: To provide normalized scatter exposure data and methods for reliable estimation of cumulative effective dose and eye-lens equivalent dose to personnel involved in fluoroscopically guided cardiac catheterization (FGCC) procedures. METHODS: An anthropomorphic phantom was placed supine on the table of a modern digital C-arm angiographic system and 17 different fluoroscopic projections commonly employed during FGCC procedures were represented. Scatter exposure rates at the waist and eye level were measured for varying exposure parameters and position in the operating room. The effect of beam field size, patient size, use of radioprotective garments and small variations in projection angulation and table height on scatter radiation was investigated. RESULTS: Apart from the position and use of radio-protective garments, radiation burden to operators during fluoroscopic guidance was found to remarkably depend beam field size (>45% reduction if a 10 × 10 cm(2) instead of 15 × 15 cm(2) fluoroscopy beam is used) and patient size (>25% increased scatter for obese patients). In contrast, the variation of measured scatter exposure from a given projection was found to be <10% when the source to skin distance was altered by ±10 cm or beam angulation of a specific projection was altered by ±10°. CONCLUSION: Presented scatter exposure data charts and methods allow for prospective and retrospective estimation of effective dose and eye-lens equivalent dose to personnel involved in any FGCC procedure. Projection specific maps of scatter exposure produced may enhance familiarization of involved medical staff to good radiation protection practice and optimization of working habits in the cardiac catheterization lab.