Estimation of occupational radiation doses in neuroendovascular procedures.

OBJECTIVE To estimate the mean effective dose per procedure with multiple dosimetry, calculate the annual effective dose to the personnel working in neuro-endovascular procedures and compare them with methods reported in the literature, and with national and international limits. METHODS Radiation dose to the personnel was monitored in 20 procedures classified between diagnostic and therapeutic. During each procedure, the equivalent dose to eyes, thyroid, under and over the lead apron at chest level, hands, gonads and knees was measured with lithium fluoride thermoluminescent dosimeter chips (TLD-100). The annual effective dose estimations were compared with different methods found in literature, using one or two dosimeters, and the data of this work in the different methods. Also, a comparison was made with the safety limits recommended by national and international regulations. RESULTS The radiation exposure to eyes, thyroid, gonads and knees are relevant to the effective dose and therefore, to the annual effective dose estimations. The personnel´s position is important as the performing physician, who is closer to the patient, received the highest dose measured. In particular, this was observed in the equivalent dose received over the apron. However, the equivalent dose to the right eye was higher for neuroanesthesiologists than for performing physicians due to their position relative to the patient. CONCLUSION In general, effective doses estimated with one and two dosimeter methods found in the literature were lower and higher than obtained with the ten dosimeters method of this work, respectively. The estimated annual effective doses to the personnel with the multiple dosimetry algorithm ranged from 1.3 to 1.5 mSv/y and are within the national and international limits.