Entrance skin dose, organ dose, and the effective dose of patients undergoing coronary angiography (CAG) and percutaneous coronary intervention (PCI) were evaluated based on the dosimetry in an anthropomorphic phantom. Tiny photodiode dosimeters embedded in various organ sites in the phantom were used to measure exposure doses. Dosimeter signals acquired on a personal computer directly were converted into absorbed doses, from which organ and the effective doses were evaluated by using the computer. Dose measurement were carried out for two types of current x-ray imager—i. e. image intensifier and flat panel detector—in fluoroscopy and in cine angiography separately for every projection of routine CAG and PCI procedure used in Nagoya Daini Red cross Hospital. Dose-area product (DAP) was also measured to examine the relations between entrance skin dose, the effective dose and the DAP. Entrance skin dose observed in PCI was in a range of 1.3-1.4Gy, the values which were less than a threshold value of 2Gy at which erythema could occur. High organ doses were observed in lung, bone surface, liver and esophagus, where the doses for lung were the highest with a value of 47mGy for CAG and 222mGy for PCI. Effective doses were evaluated to be around 10mSv for CAG, and 13-44mSv for PCI. Entrance skin dose and the effective dose were found to be independent on the types of x-ray imager, and reduced exposure doses expected for the flat panel detector could not be observed. Dose ratio of cine angiography to fluoroscopy was lower for the effective dose than for entrance skin dose. DAP to effective dose conversion coefficients were widely ranged between 0.17 and 0.52mSv/(Gy·cm
2). By using the coefficient assigned for each procedure of CAG, PCI-L and PCI-R, effective doses were possible to be estimated from measured values of DAP.
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