Radiation exposure in coronary intervention

Percutaneous transluminal coronary angioplasty (PTCA) based on plain old balloon angioplasty is the representative surgery in cardiac interventional radiography, which, with accompanying the increase of patients, causing the serious exposure problem to patients and staff. Recent progress in PTCA practice owes to the development of new devices like the stent with which reduction of exposure dose has been somewhat attained due to the short operation time. Further, standardization of the operation procedure helps to shorten the time. In author's facility, the pulse fluoroscopy stands from four modes: low-dose, normal, high-quality and slow ones. In these modes, the exposure dose, not the irradiation dose, is taken into consideration according to the FDA concept. The respective modes resulted in the reduction to 33, 70, 70 and 50% of the ordinary fluoroscopy skin dose (12.96 mGy/min: 1.49 R/min). As for exposure to operating staff, the scattering radiation was measured with the DIGITEX 2400 CX apparatus, WAC water phantom and VICTOREEN 450 ionization chamber survey meters and with shielding curtains and lead-acryl board. Shielding was found important for reduction of exposure to the staff. (K.H.)