Assessment of Radiation Dose in Neurointerventional Procedures Using a Modern Digital Fluoroscopy System

Interventional neuroradiology procedures are among those in which patients and personnel are exposed to the highest radiation dose. This study aims to measure patient doses in terms of dose-area product (DAP) and cumulative air kerma (CAK) for carotid and cerebral angiographic procedures using a digital fluoroscopy system. In addition, the staff dose was measured simultaneously with the patient dose, and the eye lens, finger, and whole-body effective dose was determined per procedure and unit DAP value. The Philips Azurion 7 M20 model C-arm fluoroscopy system was used in this study. At the beginning of the study, quality control and performance evaluations of the system were carried out. DAP and CAK measurement methods were used for patient dose measurement. Staff dose measurement was performed using beryllium oxide (BeO)-based optically stimulated luminescence (OSL) dosimeters positioned at two different points, one dosimeter under the lead apron at waist level and the other at the collar level outside the apron. With these OSL dosimeters, the personnel dose equivalent Hp(10) for the whole body at 10 mm depth, the dose equivalent Hp(3) for the 3-mm-deep eye lens, and the personal dose equivalent Hp(0.07) for the skin at 0.07 mm depth were measured. Patient dose measurements were performed for a total number of 86 patients (65 cerebral and 21 carotid). For cerebral diagnostic/therapeutic procedures, patient mean DAP and CAK values were measured as 73/143 Gy cm 2 and 657/1,888 mGy, respectively. Similarly, patient mean DAP and CAK values for carotid diagnostic/therapeutic procedures were measured as 40/79 Gy cm 2 and 487/679 mGy, respectively. Patient effective doses calculated from DAP values were 4.04/8.16 mSv and 2.11/3.93 mSv for cerebral diagnostic/therapeutic and carotid diagnostic/therapeutic procedures, respectively. Staff doses were measured for 30 cerebral and 8 carotid examinations simultaneously with patient dose measurements. The calculated whole-body effective doses per examination for the interventional radiologist, nurse, and radiologic technologist were 12.6, 7.1, and 10.0 µSv, respectively. The measured lens doses per procedure for the interventional radiologist, nurse, and radiologic technologist were 18.7, 19.7, and 13.4 µSv, respectively. The extremity doses per procedure were measured as 54.7 µSv for the interventional radiologist, 15.3 µSv for the nurse, and 14.2 µSv for the radiologic technologist.