Calculation of Conversion Coefficient for Effective Dose to Patient and Physician in Interventional Cardiology Procedure Using the Monte Carlo Method

Radiation doses to patients and to medical staff from coronary angiography procedures are relatively high when compared to conventional radiographic procedures. Due to the long image obtainment time, the high doses of radiation can result in deterministic and stochastic effects. In this work, the effective and equivalent tissue doses for the patient and medical staff were calculated and normalized to kerma-area product, to produce kerma-area to an equivalent dose in tissue conversion coefficients for this procedure. Simulations were carried out for four X-ray spectra (60, 70, 80 and 90 kVp) using the radiation transport MCNPX2.7.0 code. The physician in the standing position and the patient in the supine position were represented by a pair of adult mathematical anthropomorphic phantoms. The Conversion Coefficients (CCs) were obtained for irradiation geometry Antero-Posterior (AP), Postero-Anterior (PA), Left Anterior Oblique (LAO90°) and Right Anterior Oblique (RAO90°). The computational results demonstrated that the estimated organ dose values for the physician and patient vary significantly with the organ location and X-ray spectrum. The CCs of effective doses for the patient and physician determined in this study were compared to previous experimental and calculated results presented in the literature and found to be similar.