Study On Measuring Methods Of Dose And Dose Level Of The Eye Lens And Hand Of Occupational Staff In Interventional Procedures

Objective1. To establish methods for measuring dose of the eye lens and hand of interventional staff, using personal dose equivalent Hp(3) and Hp(0.07) to calibrate eye lens dosimeter and hand dosimeter respectively.2. To explore the feasibility of the means of measuring the eye lens dose using TLD and OSLD.3. To obtain occupational exposure dose level of relevant interventional procedures and to estimate the annual dose level of eye lens and hand.4. To provide scientific reference data for optimizing the protection of interventional staff as well as for exploring possible radiological protection measures.Methods1. Dosimeter:Two kinds of dosimeters, thermoluminescent dosimeter(TLD) and optically stimulated luminescence dosimeter(OSLD), were selected to measure the eye lens dose of occupational staff. Thermoluminescent dosimeters were used to measure the hand dose of occupational staff.2. Calibration of dosimeter:The calibration process was finished in WHO/IAEA Secondary Standard Dosimetric Laboratory. Hp(3) was defined as the operational quantity for the eye lens dose and Hp(0.07) for hand dose.3. Interventional procedures:Seven kinds of interventional procedures were shosen, including lower limb angiography and stenting, embolization of spinal cord, cerebral stent implantation, cerebral embolism, percutaneous coronary intervention, cerebral angiography, coronary angiography.4. Interventional equipments:Five types of Digital Subtraction Angiography(DSA) equipments were chosen in the study, including single tube and double tube equipment.5. Staff dose measurements:The dose of eye lens and hand of the operators were measured in first, second and third operation position.6. Measuring methods:A "conbined" dosimeter, containing thermoluminescent and optically stimulated luminescence, was worn beside the left eye; one TLD was worn beside the right eye; both hand wrists wore one TLD. Each dosimeter was read after measuring 5～10 procedures, then divided by the number of cases to obtain dose level of single procedure.Results1.154 operations of 7 different interventional procedures were measured in this study.2. Of all the interventional procedures measured, the left eye lens dose of the first operation position from high to low was:lower limb angiography and stenting 111.0 μSv, embolization of spinal cord 66.2 μSv, cerebral stent implantation 41.6 μSv, cerebral embolism 21.1 μSv, percutaneous coronary intervention 17.3 μSv, cerebral angiography 14.6 μSv, coronary angiography 10.2 μSv.3. For same interventionist of the same interventional procedure, the dose of left eye was obviously higher than that of right eye, the former was 2.0～6.6 times of the latter. For same type of interventional procedure, the eye lens dose of the operator in the first operation position was the highest, while in the third operation position was the lowest, and the left eye lens dose of the first operation position was 1.0～1.2 times of the second operation position.4. The results measured of OSLD were higher than that of TLD, the former was 1.2～4.1 times of the latter.5. Of all the interventional procedures measured, the left hand dose of the first operation position from high to low was:embolization of spinal cord 253.5μSv, lower limb angiography and stenting 209.0 μSv, percutaneous coronary intervention 97.6 μSv, coronary angiography 59.2 μSv, cerebral stent implantation 54.2 μSv, cerebral embolism 47.3 μSv, cerebral angiography 34.0 μSv.6. For same interventionist of the same interventional procedure, the dose of left hand was obviously higher than that of right hand, the former was 1.2～6.5 times of the latter. For the same type of interventional procedure, the hand dose of the operator in the first operation position was the highest, while in the third operation position was the lowest, the left hand dose of the first operation position was 1.4～2.8 times of the second operation position.7. Although the fluoroscopy time of percutaneous coronary intervention and coronary angiography was less than that of cerebral stent implantation and cerebral embolism, the hand dose level of interventional staff of the former was higher than that of the latter.Conclusions1. We preliminary established the method for measuring dose of the eye lens and hand of interventional staff, using personal dose equivalent Hp(3) and Wp(0.07) to calibrate eye lens dosimeter and hand dosimeter respectively.2. In this study, the results measured of OSLD were higher than that of TLD, the former was 1.2～4.1 times of the latter. The difference lied in the energy response angle response and other discrepancy between the two kinds of dosimeters.3. TLD can be used to measure the eye lens dose of interventional staff, while OSLD needs to be calibrated before use.4. The order of eye lens dose of different interventional procedures from high to low is:lower limb angiography and stenting> embolization of spinal cord> cerebral stent implantation> percutaneous coronary intervention> cerebral embolism> cerebral angiography> coronary angiography.5. The order of hand dose of different interventional procedures from high to low is: embolization of spinal cord> lower limb angiography and stenting> percutaneous coronary intervention> coronary angiography> cerebral stent implantation> cerebral embolism> cerebral angiography.6. For the same interventionist, the dose of left eye lens was higher than that of the right eye lens and the dose of left hand was higher than that of the right hand. For the same type of interventional procedure, the dose of the operator in the first operation position was the highest, while in the third operation position was the lowest. The position of interventionist could affect eye lens and hand dose of interventional staff.