Abstract
Purpose:
Endourology is established in urology practice with routine use of fluoroscopic guidance. Medical personnel are rarely exposed to direct radiation exposure but secondary exposure occurs via radiation scatter. There are few reports on scatter radiation exposure and the subsequent risk to medical personnel involved in urological fluoroscopic procedures. We review the risks of scatter radiation exposure to medical personnel with reference to the routine use of fluoroscopic imaging in urological practice.
Materials and Methods:
We measured staff radiation exposure during a series of ureteral endourological procedures using LiF:Mg,Ti thermoluminescent dosimeters placed at the extremities of the operating surgeon, the assistant and the scrub nurse. Doses for percutaneous nephrolithotomy (PCNL) procedures were calculated by extrapolating from the ureteral procedure thermoluminescent dosimeter data. Theoretical scattered radiation dose rates were also calculated.
Results:
The average ureteral procedure fluoroscopy time was 78 seconds with an exposure rate of 71 kV, 2.4 mA. The surgeon received the highest radiation exposure with the lower leg (11.6 ± 2.7 μGy) and foot (6.4 ± 1.8 μGy) receiving more radiation than the eyes (1.9 ± 0.5 μGy) and hands (2.7 ± 0.7 μGy). For a predicted annual caseload of 50 ureteral cases, the dose received does not exceed 0.12% of the Ionising Radiations Regulations 1999 annual dose limit for adult workers. Radiation exposure during PCNLs is higher but does not exceed 2% of the annual dose limits even if 50 PCNLs are performed annually.
Conclusions:
Fluoroscopic screening results in radiation exposure of medical personnel. The estimate of maximum scatter radiation exposure to the surgeon for 50 PCNL procedures a year did not exceed 10 mGy. This amount is less than 2% of permissible annual limits of equivalent dose to the extremities. Medical personnel should be aware of scatter radiation risks and minimize radiation exposure when involved in fluoroscopic screening procedures.
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From the Department of Urology (GOH, GT, RJM) and Department of Medical Physics (EW), The Royal Free Hospital, London, and Department of Medical Physics and Clinical Engineering, The Churchill Hospital, Oxford (SJM), United Kingdom
