Uncovering the real outcomes of active renal stone treatment by utilizing non-contrast computer tomography: a systematic review of the current literature

Flexible ureteroscopy in Chinese air force pilots with renal calculi: a cohort study at a single medical centre

INTRODUCTION

Renal calculi are the predominant urological ailment in air force pilots. Flexible ureteroscopy (FURS) constitutes a valuable approach for renal calculi treatment. This study presents a decade-long exploration of using FURS for renal calculi treatment in air force pilots. Additionally, it investigates the safety and feasibility of granting waiver flights to pilots with renal parenchyma calcification.

METHODS

From December 2009 to December 2019, a retrospective review was conducted on Chinese air force pilots undergoing treatment for renal calculi. Among the pilots assessed, a total of 71 individuals underwent FURS. Endoscopic methodology involved the insertion of a flexible ureteroscope into the ureter and renal pelvis, guided by a safety wire. Stone fragmentation was achieved using a holmium laser fibre, followed by extraction using a soft stone basket. Postoperative non-enhanced CT (NECT) scans was used to confirm stone clearance. Furthermore, clinical diagnoses were classified based on endoscopic findings and postoperative NECT results. All data were presented as mean (SD) or median (minimum-maximum) for continuous variables and frequency counts and percentages for categorical variables.

RESULTS

FURS identified free kidney stones in 60 cases among all patients. The remaining 11 cases, without free stones detected during ureteroscopy, exhibited persistent high-density spots on postoperative NECT. Of the 60 cases with stones, renal calculi were successfully cleared in 30 pilots, while the remaining 30 exhibited persistent high-density spots on NECT postsurgery. Pilots with completely cleared free stones were deemed fit for flight. Pilots with diagnosed renal parenchyma calcification were granted permission to fly under waivers following a meticulous evaluation.

CONCLUSIONS

FURS could not only effectively eliminate renal calculi but also accurately diagnose renal parenchyma calcification, facilitating a prompt return to flight for pilots. A protocol for managing pilot renal calculi, informed by FURS and our experience, is proposed.

2022 recommendations of the AFU Lithiasis Committee: Objectives, results, residual stones and fragments

The main objectives of interventional stone treatment are stone removal, symptom elimination, and kidney function preservation. After treatment of kidney stones (extracorporeal shock wave lithotripsy [ESWL], or endoscopy), fragments may remain in the kidney, either deliberately left in place or due to treatment failure (i.e. residual stone [RS], resistant to ESWL, left or inaccessible by endoscopy), or due to failure to eliminate the obtained fragments (i.e. residual fragments [RF]). Their management may differ. The most commonly used definition of RF in the literature is based on a size cut-off (≤4mm) and on three criteria: spontaneous clearance rate, secondary intervention rate, and disease progression rate. RF may be spontaneously eliminated (42%), persist and increase in size (32%), or become complicated and require a secondary urological procedure (36%). Like for the initial treatment, it is important to consider the stone composition for the treatment decision-making concerning RS/RF. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) (EAU, 2022) and their adaptability to the French context.

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.

[Follow-up after urolithiasis management]

BACKGROUND

Urinary stones often affect younger people. Because the risk of recurrence is high, regular follow-up is important for individuals at risk.

OBJECTIVE

To summarize the extent of urinary stones and the health and economic impact in the population; to provide recommendations for general and stone-specific follow-up.

MATERIALS AND METHODS

Analysis and discussion of publications and guideline recommendations.

RESULTS

The risk of recurrence after a stone attack can be high depending on the risk profile. An initial metabolic workup should be performed promptly after stone therapy. General dietary management should be intensified by stone-specific dietary management depending on the risk profile. Nutritional counseling may be helpful. Imaging after stone therapy is used to monitor the success of treatment and detect recurrences early. Since the risk of recurrence can vary greatly depending on the stone composition, not only the type of imaging but also its frequency should be adjusted accordingly. The same applies to the various stone therapies, which help determine the frequency and type of imaging follow-up. Exact guidelines and cost-effectiveness analyses of follow-up examinations after stone therapy are unfortunately missing.

CONCLUSIONS

Acute urolithiasis represents an excruciating experience for patients. Accordingly, their willingness to undergo metaphylaxis and follow-up shortly after the event is strong. Since the risk of recurrence after a stone attack can be very high, regular follow-up after stone therapy is essential. The frequency of follow-up should be adapted to the probability of stone recurrence.

Laser fibre, rather than the stone, may harm the scope: retrospective monocentric analysis of 26 pre- and intraoperative factors of flexible ureteroscope (fURS) damage

PURPOSE

The increasing number of flexible ureteroscopy procedures, the fragility of devices and their repair costs are a burden for urological departments worldwide. The objective was to investigate the impact of 26 pre- and intraoperative factors on reusable flexible ureteroscope (fURS) damage.

METHODS

All procedures were conducted with reusable fURS: Karl Storz Flex-X2 or Olympus URF-V. Statistical analysis was performed in RStudio (1.0.136) with Chi-square test and Mann-Whitney U tests (MWU).

RESULTS

In total, 416 flexible ureteroscopies, performed between September 2013 and June 2017, were analysed. 283 (68.03%) of these were for kidney stone surgery, and 133 (31.97%) for diagnostic purposes. In total, 39 (9.38%) devices were postoperatively deemed defective. The application of reusable laser fibre through fURS was more common in cases with documented defects [17/39 (43.59%) vs. 102/377 (27.06%), p = 0.047]. Other factors such as application of nitinol basket, biopsy via fURS, insertion of access sheath (UAS), as well as stone burden [median kidney stone maximal diameter: 6 mm (min 2.0; max 30.0) vs. 6 mm (min 1.0 vs. max 30.0)] showed no influence on fURS damage rate (p > 0.05). The infundibulopelvic angle (IPA) was steeper in cases with fURS damage as compared to cases without damage [median 44.0° (min 20.0; max 81.0) vs. 55.0 (min 7.0; max 122.0), p < 0.001].

CONCLUSIONS

Application of laser fibre via fURS can be considered as a risk factor of fURS damage. Stone burden, as well as the usage of not-sharp ended devices as nitinol baskets or forceps, is primarily not responsible for fURS damage.

Early ureteroscopic lithotripsy in acute renal colic caused by ureteral calculi

PURPOSE

We aimed at comparing the success and complications of early semirigid ureteroscopy (URS) and elective URS in ureteral calculi with renal colic that do not respond to analgesics.

METHODS

We retrospectively analyzed the data of 690 patients with obstructive ureteral stones who underwent URS with stone retrieval. 247 patients who underwent early URS within the first 12 h were classified as group I and 443 patients who underwent elective URS as group II. Both groups were compared in terms of age, sex, creatinine, eGFR, stone size, laterality, location and number of stones, type of lithotriptor, presence of hydronephrosis and success and complication rates.

RESULTS

The mean age of the patients was 50.4 (18-89 years) (p > 0.05). There was no statistically significant difference between the groups in terms of age, eGFR, side, presence of hydronephrosis, fever, mucosal damage, stone migration, perforated ureter, ureteral avulsion, ureteral stent insertion at the end of the surgery and sepsis (p > 0.05). Both groups had male dominance (p > 0.05). Creatinine was significantly lower in Group I (p < 0.05). The mean stone size was also significantly lower in Group I (p < 0.05). Middle and proximal ureteral calculi were more common in Group II (p < 0.05). Multiple stones were higher in Group II (p < 0.05). The dominant type of lithotriptor used was pneumatic in Group I and laser in Group II (p < 0.05). Stone-free rates (SFRs) were higher in Group I (98% vs 90% in the first month) (p < 0.05). Postoperative hematuria and infection were more common in Group II (p < 0.05).

CONCLUSIONS

In selected cases, early ureteroscopy is an effective and safe method for distal ureteral calculi smaller than 10 mm that are painful and resistant to analgesic treatment.