Radiation Reduction in the Pediatric Catheterization Laboratory Using a Novel Imaging System.

OBJECTIVES: Radiation dose was compared between two modern imaging systems with different x-ray tube technology (Megalix vs Gigalix) and detector type (amorphous vs crystalline silicon) at the same institution. BACKGROUND: Further reduction in radiation dose than currently reported may be achievable with advances in x-ray tube and detector technology. METHODS: Radiation dose (air kerma, dose-area product [DAP]) was retrospectively compared for post-transplant pediatric patients undergoing right heart catheterization/biopsy (fluoroscopy only) or "annual" catheterization with coronary angiography in one of two imaging systems between January 2014 and December 2016. Comparisons were also made with published radiation doses. RESULTS: A total of 122 right heart catheterizations with biopsy were performed in the Megalix/amorphous silicon (Si) lab and 168 in the Gigalix/crystalline Si lab. Age and weight were not statistically different for the two groups. There was a 50% decrease in median air kerma (2.2 mGy vs 1.1 mGy; P<.001) and 66% decrease in median DAP (52.2 μGy•m² vs 18.0 μGy•m²; P<.001) for the Gigalix/crystalline Si lab. A total of 24 "annual" catheterizations were performed in the Megalix/amorphous Si lab and 22 were performed in the Gigalix/crystalline Si lab. There was a 57% reduction in median air kerma (458.6 mGy vs 198.6 mGy; P<.001) and a 46% reduction in median DAP (2548.0 μGy•m² vs 1367.1 μGy•m²; P<.01) for the Gigalix/crystalline Si lab. Similar reductions were found on comparison with published doses. CONCLUSION: The Gigalix tube and crystalline Si detector decrease radiation dose by 50%-60% for fluoroscopy and cine acquisition in pediatric patients.