RESUMO
INTRODUCTION: Radiation exposure during urological procedures is still of concern in the urology community. It has been reported that percutaneous nephrolithotomy (PCNL) in supine position has less irradiation, as the puncture is mostly done under ultrasound guidance. However, it can also be done under fluoroscopy guidance. Unfortunately, data on radiation exposure during PCNL is lacking since they are often drawn from generalization and extrapolation, or they do not evaluate new procedures or different positions. The aim of our study was to compare the radiation dose depending on the position of the surgeon during PCNL. METHODS: A portable C-arm was used in standard mode (32 impulsions/second; 98 kV, 3.8 mA). Specific dosimeters were placed for lens, extremity, and torso. Anthropomorphic models and hand phantom models were used to reproduce the position of surgeon and patient (with same bone density as human) during PCNL in prone and modified supine position. Fluoroscopy time (FT) was six minutes to obtain higher exploitable signal, and the results are given for a FT of three minutes (more realistic). Ten percent of the FT is done with an angulation of 15 degrees and the rest in anteroposterior position. RESULTS: The equivalent doses (ED) are given in uSV (uncertainty k=2). During the modified supine position: neck, lens, right index finger, left thumb, and index finger received EDs of 99 (20%), 62 (18%), 437 (10%), 112 (12%), and 204 (10%), respectively. In a prone position, the phantom received ED on the neck, lens, right thumb and index finger, left thumb and index finger of 85 (20%), 92 (12%), 401 (10%), 585 (10%), 295 (10%), and 567 (10%), respectively. In both positions, the right hand seems more exposed than the left hand. CONCLUSIONS: The effective dose is 1.5- and 1.3-fold higher for lens and extremities, respectively, in prone position PCNL compared to modified supine position. Both positions are still well below the recommended limit for professional exposure.
RESUMO
INTRODUCTION: Over the past 20 years, the use of fluoroscopy to guide urologic surgical interventions has been constantly growing. Thus, in their daily practice, urologists and other operating room (OR) staff are exposed to X-radiation increasingly frequently. This raises questions as to the risks they encounter and the actions needed to reduce them. OBJECTIVE: Evaluate X-ray dose exposure in the members of the surgical team and determine urologist radioprotection knowledge and practices. MATERIALS AND METHODS: A prospective bicenter study was conducted within AFUF (French urology resident association) and in association with The French Nuclear Safety Authority/The Institute for Radiological Protection and Nuclear Safety (ASN/IRSN). Radiation exposure was measured on 12 operators using dosimeters (seven per operator), in staff-occupied locations in the OR using ionization chambers, and on anthropomorphic phantoms. A survey was used to gather information on radiation knowledge and safety practices of the AFUF members. RESULTS: Annual whole-body radiation doses were low (0.1-0.8 millisieverts [mSv], mostly at around 0.3 mSv), and equivalent doses were low for the fingers (0.7-15 mSv, mostly at around 2.5 mSv), and low for the lens of the eye (0.3-2.3 mSv, mostly at around 0.7 mSv). In percutaneous nephrolithotomy, extremity doses were lower when the patient was placed in dorsal decubitus compared with ventral decubitus. Pulsed fluoroscopy reduced radiation dose exposure by a factor of 3 compared with continuous fluoroscopy with no image quality loss. Radiation safety practices were poor: only 15% of urologists wore dosimeters and only 5% had been trained in the handling of X-ray generators. CONCLUSION: In the present study, radiation exposure for urologists was low, but so was knowledge of radiation safety and optimization practices. This absence of training for radiation safety and reduction, teamed with novel techniques involving long fluoroscopy-guided interventions, could result in unnecessarily high exposure for patients and OR personnel.