Measuring of the radiation dose received by patients and staff in neurointerventional radiology examinations using a flat panel detector based on a digital fluoroscopy system

Interventional neuroradiology examinations are among the examinations in which patients and personnel are exposed to the highest radiation dose. The aim of this thesis is to measure patient doses in terms of Dose-Area Product (DAP) and Cumulative Air Kerma (Cumulative Air Kerma, CAK) for neurointerventional radiology studies in digital angiography system. In addition, the personnel dose was measured simultaneously with the patient dose, and lens, finger and whole-body effective dose determined per examination and patient unit DAP value. In the study, an C-arm fluoroscopy system was used. At the beginning of the study, the quality control and performance measurements of the system were carried out. Dose-Area Product (DAP) and cumulative air kerma (CAK) measurement methods were used for patient dose measurement. Niklason et al. 1994 and Borrego et al. 2020 algorithms were used to calculate personnel doses. For this purpose, dose measurement was made by carrying cards containing Optically Stimulated Luminescence (OSL) dosimeter consisting of BeO crystal at two different points, one dosimeter under the lead apron at waist level and the other at the neck outside the apron. With these OSL dosimeters, the personnel dose equivalent Hp(10) for the whole body, the dose equivalent Hp(3) for eye lens and the personal dose equivalent Hp(0.07) for the skin were measured. Patient dose measurements were performed for a total of 86 patients (65 cerebral and 21 carotid). For cerebral diagnostic/therapeutic investigations, patient DAP and CAK values were measured as 73;143 Gy·cm2 and 657;1888 mGy, respectively. Similarly, patient DAP and CAK values for carotid diagnostic/therapeutic investigations were measured as 40;79 Gy·cm2 and 487;679 mGy, respectively. Patient effective doses calculated from DAP values are 4.04;8.16 mSv and 2.11;3.93 mSv for cerebral diagnostic/therapeutic and carotid diagnostic/therapeutic investigations, respectively. Staff doses were measured for a total of 30 cerebral and 8 carotid examinations simultaneously with patient doses. According to the Niklason/Borrego algorithms, the measured whole body effective doses per examination for the physician, nurse, and technician are 12.63;19.74 µSv, 7.11;11.05 µSv, and 10.00;15.26 µSv, respectively. The measured lens doses per examination for the physician, nurse, and technician were 18.68, 19.74, and 13.42 µSv, respectively. The extremity doses per examination were measured as 54.74 µSv for the physician, 15.26 µSv for the nurse and 14.21 µSv for the technician. 2023, 65 pages Keywords: Neurointerventional radiology, patient/personnel dose, DAP, air kerma, FPD, OSL