A Study of Occupational Radiation Dosimetry During Fluoroscopically Guided Simulated Urological Surgery in the Lithotomy Position

Radiation exposure of urologists during endourological procedures: a systematic review

INTRODUCTION

Ionizing radiation is used daily during endourological procedures. Despite the dangers of both deterministic and stochastic effects of radiation, there is a lack of knowledge and awareness among urologists. This study reviewed the literature to identify the radiation exposure (RE) of urologists during endourological procedures.

METHODS

A literature search of the Medline, Web of Science, and Google Scholar databases was conducted to collect articles related to the radiation dose to urologists during endourological procedures. A total of 1966 articles were screened. 21 publications met the inclusion criteria using the PRIMA standards.

RESULTS

Twenty-one studies were included, of which 14 were prospective. There was a large variation in the mean RE to the urologist between studies. PCNL had the highest RE to the urologist, especially in the prone position. RE to the eyes and hands was highest in prone PCNL, compared to supine PCNL. Wearing a thyroid shield and lead apron resulted in a reduction of RE ranging between 94.1 and 100%. Educational courses about the possible dangers of radiation decreased RE and increased awareness among endourologists.

CONCLUSIONS

This is the first systematic review in the literature analyzing RE to urologists over a time period of more than four decades. Wearing protective garments such as lead glasses, a thyroid shield, and a lead apron are essential to protect the urologist from radiation. Educational courses on radiation should be encouraged to further reduce RE and increase awareness on the harmful effects of radiation, as the awareness of endourologists is currently very low.

Impacts on air dose rates after the Fukushima accident over the North Pacific from 19 March 2011 to 2 September 2015

A fleet of thirteen in-service global container ships continuously measured the air dose rates over the North Pacific after the Fukushima Daiichi Nuclear Power Station (FDNPS) accident. The results showed that the elevated air dose rates over the Port of Tokyo and the FDNPS emissions are significantly correlated (log(emission fluxes) = 54.98 x (air dose rates) (R = 0.95, P-value<0.01), and they are also significantly correlated with the Tsukuba deposition fluxes (log(deposition fluxes) = 0.47 + 30.98 (air dose rates) (R = 0.91, P-value<0.01). These results demonstrate the direct impact of the FDNPS emissions on the depositions of radionuclides and the air dose rates over the Port of Tokyo. Over the North Pacific, the correlation equations are log(emission fluxes) = -2.72 + 202.36 x (air dose rates over the northwestern Pacific) (R = 0.40, P-value<0.01), and log(emission fluxes) = -0.55 + 80.19 x (air dose rates over the northeastern Pacific) (R = 0.29, P-value = 0.0424). These results indicate that the resuspension of the deposited radionuclides have become a dominant source in the transport of radionuclides across the North Pacific. Model simulations show underestimated air dose rates during the periods of 22-25 March 2011 and 27-30 March 2011 indicating the lack of mechanisms, such as the resuspension of radionuclides, in the model.

Ultrasound versus fluoroscopy-guided ureteroscopy for distal ureteric stones in adults

Objective

To evaluate the safety and efficacy of ultrasound (US) as alternative to fluoroscopy for guidance of ureteroscopy (URS) during treatment of distal ureteric stones in adults.

Materials and methods

This study enrolled 80 patients older than 18 years presented with a single distal ureteric radio-opaque stone of ≤15 mm in longest diameter. Patients were randomized and allocated into two groups: the fluoroscopy group and the ultrasound group (n = 40 patients in each group). Patients with bilateral ureteric stones, solitary kidney, ureteric congenital anomalies, history of failed ureteroscopy, history of ureteric surgery, patients with uremia and pregnant women were excluded. Patients’ demographics, stone characteristics, operative data, stone-free status, hospital stay and complications were evaluated in both groups.

Results

No statistically significant difference between both groups was found regarding patients’ demographics and stone characteristics. Also there was no statistically significant difference in comparing fluoroscopy group versus ultrasound group regarding operative time (29.48 ± 15.3 versus 31.28 ± 18.24 min; P = 0.83), stone-free rate (97.5% versus 95%; P = 1.0), overall complications (15% versus 12.5%; P = 0.75), or hospital stay (1.17 ± 0.6 versus 1.02 ± 0.16 days; P = 0.12). Four patients (10%) in the ultrasound group required the addition of fluoroscopy beside ultrasound.

Conclusion

Ultrasound is effective in guidance during ureteroscopy for distal ureteric stones. It was comparable to fluoroscopy in terms of stone free rate, operative time, overall complications, and hospital stay. However, fluoroscopy must be available to be used when needed.

Fluoroscopy-use during ureterorenoscopy: are urologists concerned about radiation exposure? A nationwide survey in Belgium and The Netherlands

INTRODUCTION

To evaluate the use and awareness of radiation during URS among Belgian and Dutch urologists.

MATERIAL AND METHODS

An online questionnaire was send to all members of the Belgian and Dutch Association of Urology.

RESULTS

170 urologists finished the complete questionnaire. 10% of the respondents are not familiar with the ALARA-principle. 29% starts with a KUB and 48% makes an XRPG at the beginning of the procedure. 85% uses fluoroscopy to place a wire or ureteral access sheet, 18% during stone treatment, 59% to screen for missed stones or calyces, 90% to place a JJ-stent or ureter-catheter and 23% to check for extravasation. 82% do not document radiation data. 51% does not wear a dosimeter during fluoroscopy. Almost all wear a lead apron during fluoroscopy, 47% uses additional thyroid shields and only 4% uses lead glasses. 88% intentionally reduces fluoroscopy time, 75% reduces the exposed area with a diaphragm, 72% brings the radiation source close to the patient and 44% uses pulsed fluoroscopy.

CONCLUSION

There is a wide variety in the use and awareness of radiation during URS. To further reduce radiation and its negative effect for patients and medical staff, awareness about radiation safety should increase among urologists.

Radiation exposure of patients during endourological procedures: IAEA-SEGUR study

Fluoroscopy is increasingly used to guide minimally invasive endourological procedures and optimised protocols are needed to minimise radiation exposure while achieving best treatment results. This multi-center study of radiation exposure of patients was conducted by the South-Eastern European Group for Urolithiasis Research (SEGUR), in cooperation with the International Atomic Energy Agency. Seven clinical centers from the SEGUR group collected data for 325 procedures performed within a three-months period, including standard percutaneous nephrolithotomy (PCNL), mini PCNL, retrograde intrarenal surgery (RIRS), semirigid ureterorenoscopy (URS) and flexible URS. Data included: air kerma area product (P_KA), air kerma at the patient entrance reference point (K_a,r), fluoroscopy time (FT), number of radiographic images (N) and fluoroscopy pulse rate, as well as total procedure duration, size and location of stones. Data were centrally analysed and statistically compared. MedianP_KAvalues per center varied 2-fold for RIRS (0.80-1.79 Gy cm²), 7.1 fold for mini-PCNL (1.39-9.90 Gy cm²), 7.3 fold for PCNL (2.40-17.50 Gy cm²), 19 fold (0.13-2.51 Gy cm²) for semi-rigid URS and 29-fold for flexible URS (0.10-2.90 Gy cm²). LowerP_KAandK_a,rwere associated with use of lower FT,Nand lower fluoroscopy pulse rate. FT varied from 0.1 to 14 min, a small fraction of the total procedure time, ranging from 10 to 225 min. HigherNwas associated with higherP_KAandK_a,r. Higher medianP_KAin PCNL was associated with the use of supine compared to prone position. No correlation was found between the concrement size and procedure duration, FT,P_KAorK_a,r. Dose values for RIRS were significantly lower compared to PCNL. The maximumK_a,rvalue of 377 mGy was under the threshold for radiation induced skin erythema. The study demonstrated a potential for patient dose reduction by lowering FT andN, using pulsed fluoroscopy and beam collimation.

Low Dose Fluoroscopy During Ureteroscopy Does Not Compromise Surgical Outcomes

Objective: To evaluate whether reducing the dose of fluoroscopy to ¼ of standard dose during unilateral ureteroscopy for ureteral stone treatment would impact in a reduction of total radiation emitted and whether this strategy would impact operation time, stone-free rate, and complication rate. Methods: From August 2016 to August 2017, patients over 18 years submitted to ureteroscopy for ureteral stone between 5 and 20 mm were prospectively randomized for ¼ dose reduction or standard dose fluoroscopy. Patients with abnormal urinary anatomy such as horseshoe kidney, pelvic kidney, or duplex system were excluded from the study. Results: Ninety-four patients were enrolled. The fluoroscopic dose reduction strategy to ¼ of the standard dose was able to significantly reduce the cumulative radiation emitted by C-arm fluoroscopy and the dose area product (3.6 ± 4.5 mGy vs 16.2 ± 19.3 mGy, p = 0.0001 and 0.23 ± 0.52 mcGycm² vs 1.15 ± 2.74 mcGycm², p = 0.02, respectively). Fluoroscopy time was similar between groups (74.5 ± 84.8 seconds vs 88.3 ± 90 seconds, p = 0.44). There was no need to increase the fluoroscopy dose during any of the procedures. Surgical outcomes were not affected by fluoroscopic dose reduction strategy. Conclusion: Low dose fluoroscopy reduces the emitted radiation during ureteroscopy without compromising surgical outcomes.