RESUMEN
The goal of our study was to clarify the effect of low pulse rate fluoroscopy applying in percutaneous coronary intervention (PCI) on devices' visibility and radiation dose. Four types of fluoroscopy conditions combined with two pulse rates (7.5 and 15 pulses/s) and two types of adaptive temporal filters (ATFs) (weak and strong) were used. Samples for visibility evaluation were acquired with moving phantom and devices such as stent, balloon, and guidewire. Trailing artifacts and the visibility of stent were evaluated by Scheffe's method of paired comparisons. Incident air kerma (Ka,r) and kerma area product (PKA) in the clinic were obtained under two fluoroscopic pulse rate conditions (7.5 and 15 pulses/s). As a result, in 7.5 pulses/s fluoroscopy, trailing artifacts were decreased by using weak ATF with the median value of PKA and Ka,r reduced by about 50%, but stent visibility was decreased compared to 15 pulses/s. Therefore, a combination of 7.5 pulses/s fluoroscopy and suitable ATF can bring dose reduction with avoiding trailing artifacts, but dose per pulse should be adjusted to maintain the stent visibility.
Asunto(s)
Intervención Coronaria Percutánea , Dosis de Radiación , Fluoroscopía , Humanos , Fantasmas de Imagen , Stents , ArtefactosRESUMEN
PURPOSE: National diagnostic reference levels in Japan 2020 (DRLs 2020) have been published. In the field of angiography, in addition to the fluoroscopic dose rate, incident air kerma at the patient entrance reference point displayed on the equipment (Ka,r: mGy) and air kerma-area product displayed on the equipment (PKA: Gycm2) were set. A questionnaire survey was conducted at each facility in the Tokai region to confirm the status of medical radiation dose control in the region. METHOD: A questionnaire survey was conducted at each facility in the Tokai region. The items were fluoroscopic dose rate in each area (head and neck, cardiac, chest and abdomen, and limbs), DA and DSA dose rates, and dose area product meter (Ka,r, PKA) for the main procedures in each area. RESULT: The median values in this study were lower than those in the DRLs 2020, indicating that appropriate dose control is being implemented in the Tokai region. The trends of fluoroscopic and radiographic dose rates were different in each area, and there was some variation among the facilities. CONCLUSION: We believe that the incorporation of fluoroscopic and radiographic dose rates by area into the DRLs will facilitate more appropriate dose control at each facility in the future.
Asunto(s)
Angiografía , Humanos , Dosis de Radiación , Fluoroscopía , Encuestas y Cuestionarios , Valores de ReferenciaRESUMEN
PURPOSE: It is very important to manage the radiation dose of cardiovascular interventional (CVI) procedures. Overseas, the diagnostic reference levels for cardiac interventional procedures were established with the air kerma at the patient entrance reference point (Ka,r) and the air kerma-area product (PKA). Although the Japan DRLs 2015 was established by the Japan Network for Research and Information on Medical Exposure (J-RIME), the Japan DRL for CVIs were established by fluoroscopic dose rates of 20 mGy/min at the patient entrance reference point with 20 cm thickness polymethyl methacrylate (PMMA) phantom. In the present our study, we performed a questionnaire survey of indicated values of angiographic parameters in CVI procedures. METHODS: A nationwide questionnaire was sent by post to 765 facilities. Question focused on angiographic technology, exposure parameters and radiation doses as the displayed dosimetric parameters on the angiographic machine. RESULTS: The recovery rate was 22.8% at 175 out of 765 facilities. In total 1728 cases of the coronary angiography (CAG), 1703 cases of the percutaneous coronary intervention (PCI), 962 cases of the radiofrequency catheter ablation (RFCA) and 377 cases of pediatric CVI. The 75th percentile value of Ka,r, PKA, fluoroscopy time (FT) and number of cine images (CI) for CAG, PCI, RFCA and pediatric CVI were 702, 2042, 644, and 159 mGy, respectively, 59.3, 152, 81.3, and 14.9 Gyã»cm2, respectively, 10.2, 35.6, 61.1, and 35.6 min, respectively and 1503, 2672, 722, and 2378 images, respectively. Our investigation showed that the angiographic parameters were different in several CVI procedures. CONCLUSIONS: The displayed dosimetric parameters on the angiographic machine in CVI procedures showed different values. We should classify the dosimetric parameters for each procedure.