Background: The aim of this study is to investigate outcomes of pre-operative stent dwell time on infectious complications following ureteroscopy and stone treatment to identify a time cut-off. Material and Methods: Three tertiary referral centres in Europe retrospectively collected outcomes of ureteroscopy and laser fragmentation (URSL) for all patients with pre-operative indwelling ureteric stents over a period of up to 5 years. Data was collected on patient details, stone demographics, stent dwell time, complications and stone free rate (SFR). Matching for age, sex, operative time, stone size and post-operative stent insertion. To examine for a threshold effect, monthly cut-offs were used to compare post-ureteroscopic febrile UTIs. Binomial logistic regression was used (SPSS v.24) with a significance level set at 0.0036. The risk ratio (RR) with a 95% confidence interval (CI) and the number needed to harm (NNH) are reported. Results: There were 467 patients with a pre-operative stent for analysis. These patients (n = 315) were matched to non-stented controls after excluding 152 patients to achieve adequate matching. There was a significant difference in rates of post-ureteroscopic febrile UTI between stented vs non-stented patients (RR = 2.67, 95% CI: 1.10–6.48, p = 0.03). On adjustment, a dwell time of more than two months was associated with an increased risk of post-ureteroscopic febrile UTI (RR = 3.94, 95% CI: 1.30–12.01, p = 0.02), this increased risk rose with longer dwell time. At stent time longer than four months was associated with a significantly increased risk of post-ureteroscopic febrile UTI (5% vs. 15%, RR = 3.09, 95% CI: 1.56–6.10, p = 0.001), with the number needed to harm at 10. Conclusions: Overall infectious complication rates from URSL are low. The risk of post-operative UTI after four months of dwell time is nearly tripled compared to less than four months.

Introduction: Thulium lasers (TLs), namely the Thulium fiber laser (TFL) and the Thulium:YAG (Tm:YAG), are being increasingly adopted for the conservative treatment of upper urinary tract urothelial carcinoma (UTUC). However, to date, the real clinical impact of TLs on UTUC management remains not well-characterized. We performed a review of the literature to summarize the current evidence on TLs for UTUC treatment. Materials and Methods: We performed a systematic review in January 2023 using the Embase and Medline online databases, according to the PRISMA recommendations and using the PICO criteria. Outcomes of interest were: (i) to assess the safety and feasibility of TLs in the treatment of UTUC, and (ii) to evaluate the oncological outcomes in terms of tumor recurrence and conservative treatment failure. Moreover, we described TL characteristics and its interaction with soft tissue. Results: a total of 458 articles were screened, and six full texts including 273 patients were identified. All the included studies were retrospective series. Mean patient age ranged from 66 to 73 years. The indication of a conservative treatment was elective and imperative in 21.7–85% and 15–76% of cases, respectively. Laser power settings varied from 5 to 50 W. No intraoperative complications were reported, and all the procedures were successfully performed. The tumor recurrence rate was 17.7–44%, and the indication to radical nephroureterectomy was 3.7–44% during a follow-up of 6–50 months. Most of the postoperative complications were mild and transient, and ureteral strictures were reported in two studies. Major limitations were the retrospective nature of the studies, the small sample sizes, and the short follow-up. Conclusions: TL is an effective and safe technology for endoscopic UTUC treatment. However, current available literature lacks prospective and multicentric studies with large population sizes and long-term follow-up.

Purpose: To propose and evaluate a new endoscopic technique using only a retrograde ureteroscopic approach for the removal of heavily encrusted ureteral stents. Methods: Data from 51 consecutive patients with encrusted and retained ureteral stents were prospectively collected. Description of the successive steps of surgery is detailed. The holmium yttrium aluminum garnet (Ho:YAG) laser properties offer the opportunity for fragmentation of stent-attached encrustation and the ability to cut the stent itself. Reducing the length of the stent is critical to creating space in the ureter and to allow free access for ureteroscopes or ureteral access sheath placement. The primary outcome of this study was the feasibility and the safety of this retrograde intrarenal approach. Some factors of encrustation and outcomes are also discussed in comparison with lithotripsy, percutaneous, laparoscopic, open surgery, or a combination of these techniques. Results: The removal of the encrusted stent was possible with only this retrograde technique in 98% of patients. The transection of the encrusted stent with the Ho:YAG laser was useful in 71% of the patients. Mean operative time was 110 minutes and mean hospital stay was 2.33 days. Postoperative complications were mainly nonobstructive pyelonephritis (10%). The most significant predictor of this life-threatening complication was the presence of struvite stones with the encrusted stent (p = 0.018). Contrariwise, operative time, body mass index, gender, and encrustation rate were not associated with postoperative pyelonephritis. Both cystine stone disease and pregnancy led to faster stent encrustation. Conclusions: Retrograde ureteroscopic surgery is efficient and safe for removing retained stents and associated stone burdens. The Ho:YAG laser is essential to perform the encrustation removal and sectioning of the stent.