Assessment of patient entrance skin dose (ESD) and effective dose (ED) for the most common interventional radiological exams at Mazandaran hospital

Introduction:   Nowadays we are witnessing an exponential application of interventional radiology techniques in various communities as well as Iran. Radiological technique is regarded as  the  2nd  contributing  factor in  increasing  the  amount  of  public  doses  in various societies. So that related radiation protection organization has recommended measuring patient doses resulted from such techniques. The aims of this study have been the measurement of skin entrance dose, effective dose and also calculating the parameters required to estimate the effective dose of interventional radiology systems to reduce patient doses during common diagnostic and therapeutic interventional examinations at Mazandaran hospital. Materials and methods:   After reviewing and analyzing interventional radiology examination data at an imaging center of a Mazandaran hospital over a 12 month period, the five most commonly interventional      radiology      examinations,      including      cholangiography,      liver chemoembolization, uterine fibroids embolization, bile duct stinting and brain embolization was selected for dosimetry calculations. For each examination, 10 patients were selected and their skin dose was measured using thermoluminescent dosimeters (TLDs). The effective doses resulting from these examinations were calculated using computational software (PCXMC) based on Monte Carlo calculations in an average human phantom. Results The average entrance skin dose measured for the patients cholangiography, liver chemoembolization, uterine fibroids embolization, bile duct stinting and brain embolization was 52, 139, 413, 263 and 594 mGy respectively. Effective dose resulted from the above examinations were 2.9,13, 36, 17.2 and 12 mSv respectively. Conclusion As expected, the patient dose in interventional radiology exams varied a lot because it depends on many factors including the type of medical imaging systems, complexity interventional examination, experience and skill of the operator, and patient weight.