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Interventional examinations are associated with high levels of patient exposure per examination, which makes it particularly important to monitor individual patient doses and to assess radiation risks. The aim of this study was the assessment of effective doses for fluoroscopy-guided balloon dilatation of benign esophageal strictures, whichwasperformedonpediatricpatientsaged 1 to 2 yearsatthe Departmentof Radiosurgical Methodsof Diagnosis and Treatment of St. Petersburg State Pediatric Medical University. Patient exposure patterns were basedonourowndatacollection. Thecalculationofeffectiveandorgandosesofpatientsnormalizedbythevalue of the dose area product measured during the study was carried out using PCXMC 2.0 software. The conversion coefficients from the dose area product to the effective dose were calculated using tissue weighting coefficients from the ICRP Publications 60 and 103 their values were 10.7 and 11.7 µSv/cGy cm2, respectively. The results of verification of the method indicated that the use of inappropriate conversion coefficients leads to an almost double underestimation of children’s effective doses. Differences in the values of conversion coefficients are significant and are explained by differences in voltage, source to image distance, and irradiation field size. A simplified model of patient exposure was proposed, which is described by a single irradiation field. The assessment of effective doses using multi-field and single-field irradiation model shows comparable results, which allows using the differentiated approach to the assessment of radiation doses of patients.

Children with acute pulmonary bleeding (8 cases) due to different pathology of trancheobronchial tree were followed-up at the period from 2008 to 2014. Diagnostic angiography and X-ray endovascular occlusion of bronchial arteries were performed in the case of insufficiency of conservative and endoscopic methods of hemostasis. Microembolic spheres were used for embolization of distal vessels. The embolization coils and micro-coils were applied for occlusion of great vessels. Children (5 cases) were discharged from the hospital after embolization at the terms of 6-12 months. They hadn’t any ischemic complications associated with bronchial artery occlusion. The sequelae of main disease caused deaths of 3 other kids. The X-ray occlusion is a low-invasive and highly effective method of arrest of all types of bleeding from pool of bronchial arteries. The method could be applied even in extremely severe condition of the patients.