The magnitude and distribution of doses across the hands of interventional radiologists and cardiologists have been studied. The aims were to determine the region of highest dose, investigate variations in dose distribution, and propose an effective method for dose monitoring. Doses have been measured using sets of up to 18 thermoluminescent dosemeters (TLDs) for 183 single procedures. Important factors influencing the dose to the hand are the type of procedure, particularly the access route, the X-ray equipment used, and the experience of the operator. Radiologists performing percutaneous procedures received the highest doses, because of the proximity of their hands to the X-ray tube. The majority of procedures involve a combination of twisting and prodding actions, and the relative proportions of each determine the parts of the fingers which receive a higher dose. For most interventional radiology and cardiology procedures the bases of the ring and little fingers receive the highest dose. However, during percutaneous procedures the tips of the middle and ring fingers could receive doses which were 20-30% higher than this. For radiologists and cardiologists with a mixed workload, monitoring using TLD rings located at the base of the little or the ring fingers on either hand should provide a reasonable estimate of dose to the most exposed area. Monitoring is recommended for operators who may receive over 50 mSv to their hands per year, and should be considered for operators carrying out therapeutic procedures involving patient dose-area products over 500 Gy cm2 per month.

No abstract

The purpose of this study was to ascertain the magnitude and distribution of doses to the legs of radiologists when performing interventional procedures. LiF:Mg,Ti TLD100 chips were used to measure simultaneously doses to the lower limbs and, for comparison, the hands during 100 interventional procedures. Results show leg dose was dependent upon type and complexity of procedure, equipment used and whether lead protection was available. Where no lead protection was used, the doses to the lower limbs were frequently similar to or higher than those received by the hands. The mean dose to the legs ranged from 0.19 mSv to 2.61 mSv per procedure, compared with 0.04 mSv to 1.25 mSv to the hands. During transjugular intrahepatic portosystemic shunt and embolisation procedures the leg dose could be as much as 2-3 times greater than that to the hands. When lead protection was used, the dose to the legs was reduced significantly to 0.02 mSv to 0.5 mSv per procedure. A clear linear relationship was shown between the dose-area product (DAP) reading and the dose to the feet of the radiologist. As a "rule of thumb", a DAP reading of 100 Gy cm(2) will give a dose of 1 mSv to the legs, if no lead protection was used, dropping to approximately 0.02 mSv if lead protection was present. This study demonstrates that the dose to the legs of radiologists can be higher than that to the hands when no lead protection is used. The inclusion of a lead screen to protect the legs is an effective method of dose reduction when performing interventional procedures.

The implementation of ALARP for hospital workers is considered in relation to extremity doses. Criteria are proposed which could provide guidance in determining strategies for both implementing radiation protection measures and dose monitoring for the extremities. Two groups of hospital workers have been studied, namely interventional radiologists/cardiologists, and radionuclide staff preparing and administering radiopharmaceuticals. The radiology procedures can give high doses to both the hands and legs. Those to the legs can be reduced by the use of lead rubber shields. Study of the distribution of dose across radiologists' hands has identified the ring position on the little finger as the appropriate position for dose monitoring. The variations in dose across the hands of radionuclide workers are greater, with the tip likely to receive the highest dose. The protection strategy will need to be determined for each department, because of the wide range in techniques used in handling radiopharmaceuticals. It is hoped that the criteria could aid balanced decision-making about the appropriate protection strategy and ensure that protection measures are in place where they are required, but avoid their introduction where they are unnecessary.