The effect of ureteroscope size in the treatment of ureteral stone: 15-year experience of an endoscopist

Efficacy and Safety of Semirigid Ureteroscopy Combined with Holmium:yttrium-aluminum-garnet Laser Lithotripsy for the Treatment of Proximal Ureteral Calculi: A Single-arm Meta-analysis

Background and objective

Ureteral stones are currently treated with holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy using rigid and flexible ureteroscopes. This study aims to evaluate the efficacy and safety of semirigid ureteroscopy combined with Ho:YAG laser lithotripsy for treating proximal ureteral stones in real-world studies.

Methods

The PubMed, Embase, and Web of Science databases were searched systematically to retrieve all relevant studies up to April 2024. A meta-analysis of the retrieved studies was performed using Stata 14.0 software and expressed as rate, mean difference, and 95% confidence interval (CI). The main outcomes of this meta-analysis were stone-free rate (SFR) and perioperative outcomes including operation time, hospital stay, postoperative ureteral stent placement, auxiliary procedures, and intra- or postoperative complications.

Key findings and limitations

A total of 24 studies were included in this study, including 2058 patients with proximal ureteral stones. According to the results of the combined analysis, the SFR of semirigid ureteroscopy combined with Ho:YAG laser lithotripsy for the treatment of proximal ureteral stones was 78% (95% CI [75%, 82%]), operation time was 51.03 min (95% CI [43.5, 58.56]), hospital stay was 1.62 d (95% CI [1.54, 1.70]), auxiliary procedure rate was 20% (95% CI [15%, 25%]), and postoperative complication rate was 16% (95% CI [12%, 22%]).

Conclusions and clinical implications

The results of this study show that semirigid ureteroscopic Ho:YAG laser lithotripsy is a commonly used treatment for proximal ureteral calculi, but its efficacy and safety need to be improved further, and its efficacy is not related to the diameter of the endoscope.

Patient summary

This study showed that Ho:YAG laser lithotripsy with semirigid ureteroscopes is commonly used for treating ureteral stones. However, its efficacy and safety need to be improved further, and future research should focus on these.

An international delphi survey and consensus meeting to define the risk factors for ureteral stricture after endoscopic treatment for urolithiasis

PURPOSE

Iatrogenic ureteral strictures (US) after endoscopic treatment for urolithiasis represent a significant healthcare concern. However, high-quality evidence on the risk factors associated with US is currently lacking. We aimed to develop a consensus statement addressing the definition, risk factors, and follow-up management of iatrogenic US after endoscopic treatment for urolithiasis.

METHODS

Utilizing a modified Delphi method, a steering committee developed survey statements based on a systematic literature review. Then, a two-round online survey was submitted to 25 experts, offering voting options to assess agreement levels. A consensus panel meeting was held for unresolved statements. The predetermined consensus threshold was set at 70%.

RESULTS

The steering committee formulated 73 statements. In the initial survey, consensus was reached on 56 (77%) statements. Following in-depth discussions and refinement of 17 (23%) statements in a consensus meeting, the second survey achieved consensus on 63 (86%) statements. This process underscored agreement on pivotal factors influencing US in endoscopic urolithiasis treatments.

CONCLUSIONS

This study provides a comprehensive list of categorized risk factors for US following endoscopic urolithiasis treatments. The objectives include enhancing uniformity in research, minimizing redundancy in outcome assessments, and effectively addressing risk factors associated with US. These findings are crucial for designing future clinical trials and guiding endoscopic surgeons in mitigating the risk of US.

Ureteral stricture rate after endoscopic treatments for urolithiasis and related risk factors: systematic review and meta-analysis

PURPOSE

We aimed to accurately determine ureteral stricture (US) rates following urolithiasis treatments and their related risk factors.

METHODS

We conducted a systematic review and meta-analysis following the PRISMA guidelines using databases from inception to November 2023. Studies were deemed eligible for analysis if they included ≥ 18 years old patients with urinary lithiasis (Patients) who were subjected to endoscopic treatment (Intervention) with ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), or shock wave lithotripsy (SWL) (Comparator) to assess the incidence of US (Outcome) in prospective and retrospective studies (Study design).

RESULTS

A total of 43 studies were included. The pooled US rate was 1.3% post-SWL and 2.1% post-PCNL. The pooled rate of US post-URS was 1.9% but raised to 2.7% considering the last five years' studies and 4.9% if the stone was impacted. Moreover, the pooled US rate differed if follow-ups were under or over six months. Patients with proximal ureteral stone, preoperative hydronephrosis, intraoperative ureteral perforation, and impacted stones showed higher US risk post-endoscopic intervention with odds ratio of 1.6 (P = 0.05), 2.6 (P = 0.009), 7.1 (P < 0.001), and 7.47 (P = 0.003), respectively.

CONCLUSIONS

The overall US rate ranges from 0.3 to 4.9%, with an increasing trend in the last few years. It is influenced by type of treatment, stone location and impaction, preoperative hydronephrosis and intraoperative perforation. Future standardized reporting and prospective and more extended follow-up studies might contribute to a better understanding of US risks related to calculi treatment.

Evaluation of ultrathin semirigid ureteroscopy in terms of efficiency and cost compared to flexible ureteroscopy in treating proximal ureteric stones: a prospective randomized multicenter study

PURPOSE

To investigate the outcome and cost-effectiveness of ultrathin 6-7.5-Fr semirigid ureteroscopy in treating proximal ureteric stones compared to flexible ureteroscopy.

METHODS

Two hundred and twenty patients with a solitary proximal ureteric stone were eligible for ureteroscopy (stone size = 1-2 cm). Patients were randomly subdivided into two groups: Group I included 105 patients who underwent ultrathin semirigid ureteroscopy and group II included 115 patients who underwent flexible ureteroscopy. Both groups were compared regarding successful stone access, operation time, reoperation rates, the financial cost to stone-free, complications, and stone clearance at 4 and 8 weeks.

RESULTS

Groups I and II had no significant differences regarding patient demographics, stone criteria, and hospitalization time. In contrast, the mean operative time was significantly longer in group II (p < 0.001). The overall scope-to-stone access rate was 89.5%. It was 87.6% compared to 91.3% (p = 0.32), while the stone-free rate was 81.9% versus 87.8% (p = 0.22) for groups I and II, respectively. Intraoperative and postoperative complications were statistically insignificant between the study groups. The cost/person in Egyptian pounds was 8619 ± 350 in group I, compared to 17,620 ± 280 in group II (p < 0.001); similarly, the cost to attain the stone-free rate was 8950 ± 720 in group I compared to 17,950 ± 500 in group II.

CONCLUSION

Ultrathin semirigid ureteroscopy is safe, durable, and considered a cost-effective method for treating upper ureteric calculi compared to the flexible ureteroscopy and could be considered a first treatment option in developing countries.

The initial experience of 4.5/6.5 Fr ureteroscopic laser lithotripsy under topical intraurethral anesthesia supplemented by preoperative and intraoperative medications

PURPOSE

To assess the safety and effectiveness of the 4.5/6.5 Fr ureteroscopic laser lithotripsy (URSL) under topical intraurethral anesthesia (TIUA) compared to spinal anesthesia (SA).

METHODS

A retrospective study was conducted on 47 (TIUA: SA = 23:24) patients receiving 4.5/6.5 Fr URSL from July 2022 to September 2022. For the TIUA group, atropine, pethidine, and phloroglucinol were used apart from lidocaine. In the SA group, patients received lidocaine and bupivacaine. We compare the two groups including stone-free rate (SFR), procedure time, anesthesia time, overall operative time, hospital stay, anesthesia failure, intraoperative pain, need for additional analgesia, cost, and complications.

RESULTS

The conversion rate in the TIUA group was 4.35% (1/23). SFR was 100% in both groups. Surgical waiting time and anesthesia time were longer in the SA group (P < 0.001). There were no statistical differences in operational time and intraoperative pain. Patients developed grade 0-1 ureteral injuries. Post-surgical time out of bed was noticeably faster in the TIUA group (P < 0.001). The post-operative complication rate including vomiting and back pain was lower in the TIUA group (P = 0.005).

CONCLUSION

TIUA had an equal surgical success rate and controlled patients' intraoperative pain as SA. It was superior in terms of TIUA's patient admission, waiting time for surgery, anesthesia time, post-operative time out of bed, low complications, and costs, especially for females.

A method for reducing thermal injury during the ureteroscopic holmium laser lithotripsy

Objective

Many studies have demonstrated the heat effect from the holmium laser lithotripsy can cause persistent thermal injury to the ureter. The purpose of this study was to elucidate the use of a modified ureteral catheter with appropriate firing and irrigation to reduce the thermal injury to the "ureter" during the ureteroscopic holmium laser lithotripsy in vitro.

Methods

An in vitro lithotripsy was performed using a modified catheter (5 Fr) as the entrance for the irrigation and the holmium laser fiber while using the remaining space in the ureteroscopic channel as an outlet. Different laser power settings (10 W, 20 W, and 30 W) with various firing times (3 s, 5 s, and 10 s) and rates of irrigation (15 mL/min, 20 mL/min, and 30 mL/min) were applied in the experiment. Temperature changes in the "ureter" were recorded with a thermometer during and after the lithotripsy.

Results

During the lithotripsy, the local highest mean temperature was 60.3 °C and the lowest mean temperature was 26.7 °C. When the power was set to 10 w, the temperature was maintained below 43 °C regardless of laser firing time or irrigation flow. Regardless of the power or firing time selected, the temperature was below 43 °C at the rate of 30 mL/min. There was a significant difference in temperature decrease when continuous 3 s drainage after continuous firing (3 s, 5 s, or 10 s) compared to with not drainage (p<0.05) except for two conditions of 0.5 J×20 Hz, 30 mL/min, firing 5 s, and 1.0 J×10 Hz, 30 mL/min, firing 5 s.

Conclusion

Our modified catheter with timely drainage reducing hot irrigation may significantly reduce the local thermal injury effect, especially along with the special interrupted-time firing setting during the simulated holmium laser procedure.

Cost-effectiveness of using stone cone, balloon dilator, stone basket, and entrapment device in ureteroscopic laser lithotripsy for ureteric stones

Objective

To evaluate the costs and stone-free rates of ureteroscopic laser lithotripsy (ULL) performed with and without auxiliary equipment and to compare first-time ULL with total treatment.

Methods

One hundred patients who underwent first-time ULL without the use of auxiliary equipment because its unavailability comprised the no-device ULL (ndULL) group. Additionally, 100 patients who underwent first-time ULL with the use of auxiliary equipment when necessary comprised the device ULL (dULL) group.

Results

In the ndULL and dULL groups, the stone-free rates after first-time ULL were 72% and 94% and the mean cost was US $1037 ± 15.10 and US $1452 ± 19.80 per case, respectively, with a statistically significant difference. The stone-free rates at the end of treatment were 98% and 99%, respectively, without a statistically significant difference. When secondary treatment costs were added to the first ULL costs after failed treatment, the mean total cost was US $1625 ± 12.60 in the ndULL group and US $1566 ± 11.01 in the dULL group without a statistically significant difference.

Conclusions

The stone-free rates and costs after first-time ULL were significantly different between the groups. However, after total treatment, there was no statistically significant difference between the two groups.

Long segment right ureteric stricture following ureterorenoscopy for upper ureteric stone: A disastrous complication of endourology

Background:

Nephrolithiasis is a common ailment in developing countries such as India. Ureteroscopic management has superseded shockwave lithotripsy as the common treatment for upper urinary tract stones. The process of miniaturizing the instrument along with improved quality of video processor has amplified its potential application, maintaining the procedure safe and effective. However, with its extensive use, complications have risen in parallel, and one should be aware of its adverse effects. Ureteric stricture though rare is a serious problem and risks the loss of renal function.

Case presentation:

A 37-year-old male presented with right flank pain. On evaluation, he was diagnosed with right upper ureteric stone and left renal stone. The patient suffered ureteric perforation while the right ureterorenoscopy was being performed, and an open repair was done. On postoperative follow-up, he developed long segment ureteric stricture. Boari flap ureteroneocystostomy was done.

Conclusion:

Iatrogenic ureteric injury following ureterorenoscopy is common, minor and managed conservatively. Important tips to prevent major injury are: placement of the safety guide wire across the length of the ureter, small-calibre scopes during access if a tight gripping sensation is present and the use of lubricant along the length of the ureteroscope.

Adjunction of tamsulosin or mirabegron before semi-rigid ureterolithotripsy improves outcomes: prospective, randomized single-blind study

OBJECTIVE

To evaluate efficiency and safety of adjunct tamsulosin and mirabegron therapy before semi-rigid ureteroscopy for ureteral stones.

MATERIALS AND METHODS

In this prospective, randomized, single-blind and multicentric study, participants were randomized into three groups. Group 1 was the control, participants in Group 2 used tamsulosin, and those in Group 3 used mirabegron. Operations were performed 7 days after drug administration. In all clinics, a 6/7.5-Fr ureteroscope with a laser power source for lithotripsy was used.

RESULTS

After excluding participants whose stones spontaneously passed, who discontinued medication due to adverse events and who were lost to follow-up, 186 participants were included in the final analysis. Mean age, gender, laterality, stone distribution and mean stone surface area were similar between groups. The number of participants requiring balloon dilatation was higher in the control group (23.8%) than in the tamsulosin (8.2%) and mirabegron (6.5%) groups (p = 0.006). Successful access rate was lower in the control group (81%) than in the tamsulosin (96.7%) and mirabegron (95.2%) groups (p = 0.003). Stone-free rate was lower in the control group (77.8%) than in the tamsulosin (90.2%) and mirabegron (95.2%) groups (p = 0.01). Complication rates were similar among groups.

CONCLUSIONS

Tamsulosin or mirabegron use for 1 week before semi-rigid ureteroscope increases stone access and the stone-free rate. Tamsulosin or mirabegron can be used with safety and efficacy before ureteroscopy for ureteral stones.

Ureteral stricture after ureteroscopy for stones: A prospective study for the incidence and risk factors

Context:

A ureteral stricture is a serious complication of ureteroscopy (URS) that was reported in the literature in highly variable rates from 0.2% to 24%.

Aims:

Our aims are to estimate the incidence and to detect the risk factors of ureteral stricture after URS.

Settings and Design:

This is a prospective, case-series study.

Materials and Methods:

During the period from May 2015 to August 2016, 251 adult patients underwent 263 URS for the treatment of 304 ureteral stones. Postoperative regular follow-up was done for 12 months by ultrasound. Computed tomography urography and diuretic renogram were performed for the cases developed hydronephrosis to confirm and detect the level of the stricture.

Statistical Analysis:

IBM SPSS Statistics for Windows, Version 19.0, Armonk, NY: IBM Corp. used for data analysis. Chi-square and Fisher's exact tests were used to compare between qualitative variables. Mann–Whitney test was used to compare between two quantitative variables in case of nonparametric data. Multiple logistic regression analysis was done to measure the risk factors. P value was considered statistically significant when <0.05.

Results:

The mean age was 43.5 years (standard deviation [SD]: ±13.6), and the mean body mass index was 28.39 (±3.96). The mean total stone burden was 12.8 mm (SD: ±5.9). Bilateral URS was performed in 12 cases. The mean operative time was 54.8 min (SD: ±22.68). Initial and final stone-free rates were 83.3% and 100%, respectively. The overall complications rate was 28.1%. Stricture occurred in four cases (1.5%).

Conclusions:

In our experience, the incidence of post-URS ureteral stricture is low. The impacted stone is the most common cause of URS complications and hence stricture formation.

Efficacy of mirabegron in medical expulsive therapy

To show the efficacy of mirabegron for medical expulsive treatment, in patients had intramural located distal ureteral stone. A 80 patients had intramural ureteral stone were assessed retrospectively between April 2017 and January 2018. Mirabegron 50 mg/day + diclofenac 100 mg/day (group 1, n = 40), and only diclofenac 100 mg/day (group 2, n = 40) were administered to patients, consecutively. Age, gender, stone size, laterality, and severity of hydronephrosis were recorded. Spontaneous stone expulsion rates (SER), stone expulsion time, and the number of daily colic episodes were evaluated. In the group 1, one (2.5%) patient was excluded due to nasopharyngitis, and one (2.5%) patient was excluded due to 5 mmHg systolic blood pressure increase. In addition, four (10%) patients in group 1, and six (15%) patients in group 2, who did not attend follow-up examinations, were excluded from the study. There was not any statistically significant difference between the two groups in terms of age, gender, stone location, severity of hydronephrosis, stone size (p = 0.736, p = 0.310, p = 0.467, p = 0.801, p = 0.761, consecutively). Spontaneous expulsion ratios were calculated as 73.52% in group 1, and 47.05% in group 2 (p = 0.026). However, there was not any statistically significant difference in terms of stone expulsion time (p = 0.979). SER for patients had ≤ 6 mm stones was higher in group 1 (87.5 vs 52.49%, p = 0.031). In addition, group 2 patients had more pain episodes (1.02 ± 0.52 vs. 1.29 ± 0.57, p = 0.049). In the current study, mirabegron has been shown to be an efficient, safe and a new treatment modality, with lower side effect profile for the intramural located distal ureteral stones.

Prevention strategies for ureteral stricture following ureteroscopic lithotripsy

Ureteral stricture formation after ureteroscopic lithotripsy is a late complication that can lead to hydronephrosis and a subsequent risk of renal deterioration. The specific incidence is unknown, and the mechanism of stricture formation has not been completely explained. In this review, we summarize the current evidence regarding the incidence of this condition and discuss its pathogenesis. We then list preventive strategies to reduce the morbidity of ureteral strictures.