Radiation exposure to the urology surgeon during retrograde intrarenal surgery

Effect of Protective Eyewear on Physicians' Lens Exposure during Fluoroscopy

ABSTRACT

The ICRP 2011 Seoul Statement recommended a reduction in the dose limit for lens exposure to 100 mSv for 5 y and 50 mSv for 1 y. Based on this recommendation, the dose limit for lens exposure was lowered in Japan with the revision of the Ionization Regulations, which took effect in April 2021. In the present study, lens doses were measured during fluoroscopic procedures performed in four departments (Urology, Pediatrics, Gastroenterology, and Orthopedics). Lens doses were measured without protective eyewear for 6 mo (pre-intervention) and then with protective eyewear for the next 6 mo (post-intervention). Monthly doses were collected and lens doses before and after the use of protective eyewear were calculated as the lens dose per unit time. The use of protective eyewear reduced the lens dose per unit time by approximately two thirds. In all departments, the lens dose was slightly lower after than before the intervention. A significant difference was observed in lens doses between the pre- and post-intervention periods in the Urology department. The present results demonstrated the effectiveness of protective eyewear in daily practice. Therefore, the use of protective eyewear is recommended during fluoroscopic procedures.

Real-Time Dosimetry in Endourology: Tracking Staff Radiation Risks

BACKGROUND

To retrospectively investigate scatter radiation (SCR) exposure among staff in the endourology operating theatre.

METHODS

During surgeries under fluoroscopic guidance, five professional groups (urological surgeon [US], surgical nurse [SN], assistant surgical nurse [ASN], anaesthetist [A], and anaesthesia care [AC]) wore real-time dosimeters (Philips DoseAware System) on their head and chest over lead aprons between July 2023 and February 2024. The SCR data were analysed and correlated with procedural and patient factors.

RESULTS

In total, 249 procedures were performed, including 86 retrograde intrarenal surgeries and 10 percutaneous nephrolithotomies. Median SCR exposure was 38.81, 17.20, 7.71, 11.58, 0.63, 0.23, 0.12, and 0.15 Microsievert (µSv) for US chest (USC), US head (USH), SN chest (SNC), SN head (SNH), A chest (AC), AC chest (ACC), ASN chest (ASNC), and ASN head (ASNH), respectively. There was a significant correlation between DAP and SCR doses detected by USC, USH, SNC, SNH, AC, and ACC dosimeters (p < 0.05). The median chest-to-eye conversion factor (CECF) was 2.11 for the US and 0.71 for the SN.

CONCLUSIONS

This study, using real-time dosimetry, is among the first to assess staff occupational SCR exposure in endourology. It highlights a substantial SCR exposure, indicating an occupational health hazard that warrants further investigation.

Utilization of Ureteral Access Sheath in Retrograde Intrarenal Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: This paper evaluates the efficacy and safety of ureteral access sheath (UAS) utilization in retrograde intrarenal surgery (RIRS). Materials and Methods: We searched PubMed, Embase, and the Cochrane Library up to 30 August 2023. The inclusion criteria comprised English-language original studies on RIRS with or without UAS in humans. The primary outcome was SFR, while the secondary outcomes included intraoperative and postoperative complications, the lengths of the operation and the hospitalization period, and the duration of the fluoroscopy. Subgroup analyses and a sensitivity analysis were performed. Publication bias was assessed using funnel plots and Egger's regression tests. Dichotomous variables were analyzed using odds ratios (ORs) with 95% confidence intervals (CIs), while mean differences (MDs) were employed for continuous variables. Results: We included 22 studies in our analysis. These spanned 2001 to 2023, involving 12,993 patients and 13,293 procedures. No significant difference in SFR was observed between the UAS and non-UAS groups (OR = 0.90, 95% CI 0.63-1.30, p = 0.59). Intraoperative (OR = 1.13, 95% CI 0.75-1.69, p = 0.5) and postoperative complications (OR = 1.29, 95% CI 0.89-1.87, p = 0.18) did not significantly differ between the groups. UAS usage increased operation times (MD = 8.30, 95% CI 2.51-14.10, p = 0.005) and fluoroscopy times (MD = 5.73, 95% CI 4.55-6.90, p < 0.001). No publication bias was detected for any outcome. Conclusions: In RIRS, UAS usage did not significantly affect SFR, complications, or hospitalization time. However, it increased operation time and fluoroscopy time. Routine UAS usage is not supported, and decisions should be patient-specific. Further studies with larger sample sizes and standardized assessments are needed to refine UAS utilization in RIRS.

Ureteral access sheaths in RIRS: a retrospective, comparative, single-center study

OBJECTIVES

To evaluate the use of ureteral access sheaths (UAS) in reducing operative time and complications, as well as improving stone-free rates (SFR), while assessing their overall safety and efficiency.

METHODS

Data regarding 234 patients who underwent retrograde intrarenal surgery (RIRS) for stones up to 3 cm between January 2017 and March 2020 were retrospectively analyzed. About 52.5 % of procedures were performed utilizing a UAS. Differences in operative time, fluoroscopy time, stone-free rate, and complications were analyzed between procedures with and without UAS and stratified, according to stone burden size, into three groups (Group A: 0.5-1 cm; Group B: 1-2 cm; Group C: 2-3 cm).

RESULTS

Operative time, fluoroscopy time, and residual fragments size were lower in RIRS without UAS, respectively, 54.27 ± 24.02 vs. 62.23 ± 22.66 min (p=0.010), 2.72 ± 0.89 vs. 4.44 ± 1.67 min (p<0.0001), and 3.85 ± 0.813 vs. 4.60 ± 0.83 mm (p=0.011). Considering stone burden, operative time was lower in RIRS without UAS for Group A (36.40 ± 8.555 vs. 46.05 ± 6.332 min) (p<0.0001) while higher for Group B (60.39 ± 18.785 vs. 50.14 ± 5.812 min) (p=0.002). Similarly, fluoroscopy time was lower in RIRS without UAS in every group, respectively, 2.11 ± 0.34 vs. 2.74 ± 0.57 min (p<0.0001), 2.94 ± 0.51 vs. 4.72 ± 0.37 min (p<0.0001), and 3.78 ± 1.26 vs. 6.79 ± 1.17 min (p<0.0001). Only Group C had a statistically significant difference in residual fragment size without UAS (3.89 ± 0.782 vs. 4.75 ± 0.886 mm) (p=0.050).

CONCLUSIONS

UAS should be carefully evaluated considering the increased fluoroscopy time and the differences in operative time related to different stone burdens.

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.

First prospective clinical assessment of the ILY® robotic flexible ureteroscopy platform

PURPOSE

To present the initial prospective clinical assessment of the ILY® robotic ureteroscopy manipulator platform, focusing on its safety and effectiveness.

METHODS AND MATERIALS

Data gathered from 31 kidney units which underwent elective robotic flexible ureteroscopy (FURS) for renal stone management utilizing the ILY® robotic system. Patient demographics, stone characteristics, surgical durations, perioperative and post-operative complications, and follow-up parameters were collected. Our primary outcome was evaluating the efficacy and safety of the ILY® robotic ureteroscopy for treating kidney stones. Therefore, we analyzed complication rates, surgical durations, and the stone-free rate during follow-up.

RESULTS

Our cohort consisted of 29 patients, presenting with 45 stones with a median volume of 736.22 mm3. The median operation time was 85 min, accompanied by 3 min for robot draping, 3.5 min for robot docking, 48 min of console operation, and lasing time of 36.75 min. Post operative stay for all patients was 1 day, while complications were observed in 9.68% of cases. Notably, all complications were classified as CVD (Clavien-Dindo) class 1 due to pain requiring emergency department visit. The stone-free rate achieved was 93.55%, and none of the patient required reoperation for the treated stone.

CONCLUSION

In the first prospective clinical experience of the ILY® robotic FURS, we demonstrated its efficacy and safety. To further investigate its clinical practical value, additional investigations are warranted, including direct comparative analyses with manual flexible ureteroscopy techniques.

Radiation exposure in emergency ureteric stenting: A subgroup analysis by operator

Objectives

To review radiation exposure during emergency ureteric stent insertion to identify differences based on operator experience, specialty operator and stone characteristics.

Patients and methods

A retrospective audit over 10 years was performed for patients who underwent emergency stent insertion for urolithiasis with intraoperative fluoroscopy. Outcomes measured included operator experience, radiation exposure (mGy), dose area product (Gy/cm2), fluoroscopy time, stone characteristics and patient BMI. Analysis was performed in IBM SPSS Version 28. p < 0.05 was considered statistically significant.

Results

Four hundred ten patients were identified, with a median age of 57 years, 64.6% male and a median BMI of 30. Urolithiasis was left-sided in 50.8%, with a median size of 7 mm and predominantly proximal (49%) followed by mid (34.5%) and distal (12.1%) location. Median radiation exposure was 12.6 mGy, 2.94 Gy/cm2 and fluoroscopy time 44.5 s, with no significant difference between consultants and registrars. No significant association between radiation exposure for subgroups of stone location, gender, size, laterality or specialty registrar (general surgery vs. urology).

Conclusion

No significant difference in radiation exposure was identified between registrars and consultants or between subspecialty registrars. We suggest formal radiation safety education for all health professionals involved with intra-operative fluoroscopy and personal dosimeters.

Efficacy and safety of fluoroless ureteroscopy and retrograde intrarenal surgery for the treatment of urolithiasis: A comparative study

INTRODUCTION

Ureteroscopy (URS) and retrograde intrarenal surgery (RIRS) are traditionally guided by fluoroscopy, but the risks of exposure to ionizing radiation may present a matter of concern for patients and urologists. The aim of this study was to evaluate the efficacy and safety of fluoroless URS and RIRS compared with conventional fluoroscopy-guided procedures for the treatment of ureteral and renal stones.

MATERIAL AND METHODS

Patients treated with URS or RIRS for urolithiasis between August 2018 and December 2019 were retrospectively evaluated and grouped according to the use of fluoroscopy. Data was collected from individual patient records. The main outcomes were stone-free rate (SFR) and complications, compared between the fluoroscopy and fluoroless groups. A subgroup analysis by type of procedure (URS and RIRS) and a multivariate analysis to identify predictors of residual stones were conducted.

RESULTS

A total of 231 patients met the inclusion criteria: 120 (51.9%) in the conventional fluoroscopy group and 111 (48.1%) in the fluoroless group. No significant differences were found between groups regarding SFR (82.5% vs 90.1%, p=.127) or postoperative complication rate (35.0% vs 31.5%, p=.675). In the subgroup analysis these variables did not present significant differences, regardless of the procedure considered. In the multivariate analysis the fluoroless technique was not an independent predictor of residual lithiasis (OR 0.991; 95% IC 0.407-2.411; p=.983), when adjusted for procedure type, stone size and stone number.

CONCLUSION

URS and RIRS can be done without fluoroscopic guidance in selected cases, without affecting the efficacy or safety of the procedure.

Dose Optimization Using a Deep Learning Tool in Various CT Protocols for Urolithiasis: A Physical Human Phantom Study

Background and Objectives: We attempted to determine the optimal radiation dose to maintain image quality using a deep learning application in a physical human phantom. Materials and Methods: Three 5 × 5 × 5 mm3 uric acid stones were placed in a physical human phantom in various locations. Three tube voltages (120, 100, and 80 kV) and four current-time products (100, 70, 30, and 15 mAs) were implemented in 12 scans. Each scan was reconstructed with filtered back projection (FBP), statistical iterative reconstruction (IR, iDose), and knowledge-based iterative model reconstruction (IMR). By applying deep learning to each image, we took 12 more scans. Objective image assessments were calculated using the standard deviation of the Hounsfield unit (HU). Subjective image assessments were performed by one radiologist and one urologist. Two radiologists assessed the subjective assessment and found the stone under the absence of information. We used this data to calculate the diagnostic accuracy. Results: Objective image noise was decreased after applying a deep learning tool in all images of FBP, iDose, and IMR. There was no statistical difference between iDose and deep learning-applied FBP images (10.1 ± 11.9, 9.5 ± 18.5 HU, p = 0.583, respectively). At a 100 kV-30 mAs setting, deep learning-applied FBP obtained a similar objective noise in approximately one third of the radiation doses compared to FBP. In radiation doses with settings lower than 100 kV-30 mAs, the subject image assessment (image quality, confidence level, and noise) showed deteriorated scores. Diagnostic accuracy was increased when the deep learning setting was lower than 100 kV-30 mAs, except for at 80 kV-15 mAs. Conclusions: At the setting of 100 kV-30 mAs or higher, deep learning-applied FBP did not differ in image quality compared to IR. At the setting of 100 kV-30 mAs, the radiation dose can decrease by about one third while maintaining objective noise.