Radiation exposure reduction using an equalization filter during percutaneous coronary intervention: a preliminary study.

This study aimed to evaluate radiation exposure reduction in patients and physicians with an equalization filter (EF) in percutaneous coronary intervention. An anthropomorphic phantom was placed on the examination table in the interventional fluoroscopy system. An ionization chamber was attached to the X-ray tube to measure the X-ray output. A solid-state survey meter was placed at the physician's position. EF positions were defined as 'Shallow', 'Deep', 'Both', 'Right', and 'Left'. The X-ray output and H*(10) with and without EFs were measured at 80-160 cm increments of 20 cm with 10 C-arm angulations. The air kerma was almost identical with and without EFs. The EF reduced kerma-area product and H*(10) by a maximum of 27.4%. The average H*(10) reduction of 'Deep' was larger than that of 'Shallow' in order of 'Both' > 'Left' > 'Right'. EFs contribute to reducing patient and physician exposure while maintaining X-ray output.