The Efficacy of Ureteroscopy Without Fluoroscopy for Ureteral and Renal Stones in Pediatric Patients

Radiation exposure of patients during endourological procedures

PURPOSE

Considering the existing gaps in the literature regarding patient radiation dose (RD) and its associated risks, a systematic review of the literature on RD was conducted, focusing on percutaneous nephrolithotomy (PCNL), extracorporeal shock wave lithotripsy (SWL), and ureteroscopy (URS).

METHODS

Two authors conducted a literature search on PubMed, Web of Science, and Google Scholar to identify studies on RD during endourological procedures. Two thousand two hundred sixty-six articles were screened. Sixty-five publications met the inclusion criteria using the PRISMA standards.

RESULTS

RD was generally highest for PCNL, reaching levels up to 33 mSv, 28,700 mGycm2, and 430.8 mGy. This was followed by SWL, with RD reaching up to 7.32 mSv, 13,082 mGycm2, and 142 mGy. URS demonstrated lower RD, reaching up to 6.07 mSv, 8920 mGycm2, and 46.99 mGy. Surgeon experience and case load were inversely associated with RD. Strategies such as optimizing fluoroscopy settings, implementing ultrasound (US), and following the ALARA (As Low As Reasonably Achievable) principle minimized RD.

CONCLUSIONS

This is the first systematic review analyzing RD, which was generally highest during PCNL, followed by SWL and URS. There is no specific RD limit for these procedures. Implementation of strategies such as optimizing fluoroscopy settings, utilizing US, and adhering to the ALARA principle proved effective in reducing RD. However, further research is needed to explore the factors influencing RD, assess their impact on patient outcomes, and establish procedure-specific reference levels for RD.

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.

Fluoroscopy-free RIRS on the second session after ureteral stent placement

Aim:

Fluoroscopy is used in some stages of the conventional Retrograde Intrarenal Surgery (RIRS) procedure and is beneficial. On the other hand, radiation exposure is its most obvious disadvantage. As a subgroup, we aimed to show that fluoroscopy-free technique is safe and effective in patients who underwent RIRS after passive dilatation.

Materials and methods:

Between October 2018 and April 2020, 54 cases of second session RIRS of renal stones performed by a single surgeon were retrospectively evaluated. Patients’ demographic characteristics (age, gender), stone features (laterality, size, number, volume, and location), mean operative time, and, perioperative and postoperative complications, as well as the stone-free rate (SFR), were all retrospectively evaluated. The results were classified as stone free, clinical insignificant residual fragments (CIRF), and presence of residual stones. Complications were graded using the Clavien–Dindo classification system. We used a modified surgical technique.

Results:

All of complications were minor. There were no major complications (Clavien grade III–IV). The stone-free rate was 70.3% (38/54) on the first day after surgery and 83.3% (45/54) 1 month afterward, respectively. If we accept the absence of residual stone as success, we can say that it is about 91% successful in the first month.

Conclusion:

This technique has a high stone-free success rate and a low complication rate without the use of radiation. For surgeons experienced in endourology, we can say that the fluoroscopy-free technique is safe and effective in secondary-session RIRS cases which passive dilatation was performed by inserting a ureteral catheter before.

Flat Panel Detector c-Arms Are Associated with Dramatically Reduced Radiation Exposure During Ureteroscopy and Produce Superior Images

Background: We wished to determine whether newly available flat panel detector (FPD) c-arms were (1) associated with lower radiation dose during ureteroscopy (URS) than conventional image intensifier (CII) c-arms and (2) to compare fluoroscopic image quality between the units. Materials and Methods: We retrospectively reviewed 44 consecutive patients undergoing URS at a pediatric hospital, with c-arms assigned by availability in the operating room. We performed dosimetry experiments using the same c-arms on standard phantoms. Results: Patient and case characteristics did not differ significantly between the two groups of patients. The median dose in the FPD group was less than a quarter of the dose in the CII group, 0.48 [0.42, 0.97] mGy vs 2.2 [1.1, 3.8] mGy, p < 0.0001. The FPD dose remained at less than one-third of the CII dose accounting for any difference in fluoroscopy time, and remained significant in a multivariate model including fluoroscopy time and patient weight (β = 2.4, p = 0.007). Phantom studies showed higher image quality for FPDs at all simulated patient sizes, even at lower radiation doses. Conclusions: This is the first report comparing radiation dose from c-arms of image intensifiers and FPDs in adults or children. Use of an FPD during URS was associated with a substantially decreased absorbed dose for patients while simultaneously improving image quality.

Minimizing radiation dose in management of stone disease: how to achieve 'ALARA'

PURPOSE OF REVIEW

Exposure to radiation is known to have adverse effects such as secondary malignancies. Patients with nephrolithiasis are exposed to radiation in the workup and treatment of their condition. Furthermore, exposure to radiation is often repeated due to the high recurrence rate of nephrolithiasis.

RECENT FINDINGS

We discuss practices inside and outside of the operating room to strive to keep radiation exposure as low as reasonably achievable (ALARA) for patients being treated for nephrolithiasis. These efforts include reduced dose computed tomography scans, fluoroless surgical techniques and new alternative technologies.

SUMMARY

Maintaining radiation exposure ALARA for our patients is increasingly practical. The urologist must make every effort to adhere to ALARA principles to protect patients from the stochastic effects of radiation.

Systematic Review and Meta-Analysis Comparing Fluoroless Ureteroscopy and Conventional Ureteroscopy in the Management of Ureteral and Renal Stones

Context: Stone recurrence is frequent in stone formers, and repeated diagnostic and therapeutic procedures in recurrent stone formers place patients and urologists at a significant risk of radiation-related effects. Objective: To assess the efficacy and safety of fluoroless ureteroscopy (fURS) compared with conventional ureteroscopy (cURS) in the management of ureteral and renal stones. Evidence Acquisition: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies providing data on the stone-free rate (SFR), secondary procedures, operative time (OT), and complication rate for fURS and cURS were included. An overall analysis and a subgroup analysis based on the stone target (ureteral stones, renal stones, or a combination thereof) were performed. Evidence Synthesis: A total of 23 studies were included, recruiting 4029 patients. Pooled data showed that in comparison with cURS, fURS exhibited a similar SFR (odds ratio [OR]: 0.99; 95% confidence interval [CI]: 0.92 to 1.06; p = 0.709), without significant differences in overall intraoperative complication rate (OR: 0.73; 95% CI: 0.33 to 1.63; p = 0.446), overall postoperative complication rate (OR: 0.98; 95% CI: 0.59 to 1.63; p = 0.949), major postoperative complication rate (Clavien ≥3; OR: 0.46; 95% CI: 0.14 to 1.53; p = 0.205), OT (standardized mean difference [SMD]: 0.07; 95% CI: -0.15 to 0.29; p = 0.537), hospital stay (SMD: -0.12; 95% CI: -0.26 to 0.02; p = 0.084), or secondary procedures (OR: 1.20; 95% CI: 0.58 to 2.49; p = 0.616). The subgroup analysis revealed no differences in outcomes according to the stone target. We also identified a rate of conversion to the conventional technique of 5% (95% CI: 3% to 7%). Conclusions: The available data suggest that for the treatment of ureteral and renal stones, fURS offers a similar SFR to that provided by the cURS without any increase in complication rate, OT, hospital stay, or secondary procedures. Critical review of the dogmatic routine use of fluoroscopy during ureteroscopy may be warranted.

Outcomes of Ureteroscopy vs Mini-Percutaneous Nephrolithotomy for Pediatric Upper Urinary Tract Calculi: Comparative Nonrandomized Outcomes from Two Tertiary Endourology Referral Centers

Introduction: Pediatric upper urinary tract calculi can be treated by ureteroscopy (URS) or mini-percutaneous nephrolithotomy (mPCNL). We wanted to compare outcomes of URS and mPCNL from two tertiary referral centers that specialized in one of these treatments for pediatric stone disease. Materials and Methods: Data were collected from two tertiary centers for a 10-year period (2010-2019); one center specializing in URS and the other in mPCNL for consecutive patients ≤16 years undergoing either of these minimally invasive interventions. Upper urinary tract stones included stones in the kidney, pelviureteral junction, and proximal ureter, whereas mid or distal ureteral stones were excluded. Data were collected on patient and stone demographics. Outcomes of interest included stone-free rate (SFR) and complication rates. Results: During the study period, 55 patients underwent URS (group 1) and 40 patients underwent mPCNL (group 2). The mean stone size for groups 1 and 2 were 11.4 and 14.5 mm, respectively, whereas twice as many patients in group 1 had multiple stones. The final SFR and complication rates for groups 1 and 2 were 100% and 97.5%, and 5.4% and 12.5%, respectively. Although there were two Clavien II and one Clavien IV complication in the URS group, all five complications in mPCNL group were Clavien I. Conclusions: Our study shows excellent outcomes for upper urinary tract stones with both URS and mPCNL. Although treatment choices should be tailored to patients, each modality carries different advantages and our results reflect that high-volume centers specializing in a particular technique offer best outcomes, and this must also be borne in mind when counseling patients.

Is fluoroscopy necessary during flexible ureteroscopy for the treatment of renal stones?

Objective

To investigate the feasibility and effectiveness of flexible ureteroscopy (fURS) without fluoroscopy during the treatment of renal stones.

Patients and methods

Between April 2013 and August 2018, 744 patients’ data were evaluated retrospectively. Of these, 576 patients were included in the study. All fURS were performed by experienced surgeons. All procedures were planned with zero-dose fluoroscopy. But, if fluoroscopy was necessary for any reasons, these patients were excluded from the study. Demographic data, perioperative parameters, stone-free rate (SFR), and complication rates were recorded.

Results

Of the patients planned for fluoroless fURS (ffURS), the procedure was successfully achieved in 96.7% (557/576 patients), as 19 patients required fluoroscopy during the procedure for various reasons. In the patients included in the study, the mean (SD) stone size was 11.6 (5.2) mm and the mean (SD) operating time was 39.4 (8.2) min. After the first session of ffURS, the SFR was 83.3% (achieved in 464 patients). Second and third sessions of ffURS were performed in 32 (5.7%) and seven (1.2%) patients, respectively. Overall, the complication rate was 11.8% and all complications were minor (Clavien–Dindo Grade I or II).

Conclusions

The ffURS technique seems to be a safe and effective treatment compared to conventional fURS in patients with renal stones. This procedure should be performed in experienced centers, where fluoroscopy can be considered not to be mandatory during fURS.

Abbreviations CIRF

clinically insignificant residual fragment; CT: computed tomography; EAU: European Association of Urology; (f)fURS: (fluoroless) flexible ureteroscopy; FT: fluoroscopy time; KUB: plain abdominal radiograph of the kidneys, ureters and bladder; mSv: millisievert; PCNL: percutaneous nephrolithotomy; pps: pulse-per-second; rem: roentgen equivalent man; PUJ: pelvi-ureteric junction; SFR: stone-free rate

Approaches to Eliminate Radiation Exposure in the Management of Pediatric Urolithiasis

PURPOSE OF REVIEW

Traditional management of pediatric urolithiasis has been associated with a significant amount of radiation exposure. The steady increase in pediatric urolithiasis in recent years has raised concerns of long-term consequences in this special population. This review seeks to highlight the newer insights towards eliminating radiation exposure in pediatric urolithiasis from contemporary literature.

RECENT FINDINGS

Establishing a clinical care pathway restricting usage of computed tomography in emergency rooms in suspected pediatric urolithiasis can eliminate unnecessary radiation exposure. Ultrasound can successfully replace fluoroscopy at ureteroscopy and percutaneous nephrolithotomy. Accredited technicians who use optimized settings combined with dose monitoring can significantly reduce fluoroscopic radiation. Radiation exposure in pediatric urolithiasis can be significantly reduced and potentially eliminated by employing standard protocols during workup, intervention, and follow-ups. Larger studies can support the feasibility of routinely performing ultrasound-guided surgeries instead of fluoroscopy. There is a need for development of consensus towards standardization of the management of pediatric urolithiasis.