European Association of Urology Section of Urolithiasis and International Alliance of Urolithiasis Joint Consensus on Percutaneous Nephrolithotomy

Percutaneous nephrolithotomy or flexible ureteral lithotripsy, which one is better for patients with upper ureteral calculi of 1.5-2.0 cm in diameter

PURPOSE

First research to evaluate the clinical efficacy and safety of flexible ureteral lithotripsy (FURSL) and percutaneous nephrolithotomy (PCNL) in the treatment of the upper ureteral stone is between 1.5 cm and 2.0 cm in diameter since there is no consensus with such ureteral stone yet.

METHODS

From December 2018 to October 2022, 104 patients with calculi in the upper ureter received percutaneous nephrolithotomy (PCNL)or flexible ureteroscopic lithotripsy (FURSL) in our institution. The clinical data of the patients in the two groups were retrospectively searched. Stone removal rate, operation time, blood loss, postoperative pain score, postoperative inflammatory factor, postoperative complication rates and ureteral obstruction three months after the operation were compared between the two groups.

RESULTS

A total of 104 patients were included in the study. The stone clearance rate and the secondary surgery rate were 88.89% and 7.41% in the FURSL group, the figures were 97.96% and 2.0% in the PCNL group (p = 0.067, 0.497). Regarding ureteral obstruction three months after the operation, there were 2 patients in FURSL group and 0 patients in PCNL group(p = 0.497).Compared to patients in FURSL group, patients in the PCNL group had shorter operation time(PCNL 71.81 ± 18.94 min vs. FURSL 86.80 ± 22.49 min, p = 0.0004), fewer complications(PCNL 20.37% vs. FURSL 6.12%), and lower postoperative inflammatory factor(p = 0.0004), yet they got more hemoglobin drop (PCNL 13.14 ± 9.81 g/L vs. FURSL 4.77 ± 3.55 g/L, p < 0.0001), higher postoperative pain scores(p = 0.0017) in the first three postoperative days and longer hospital stay (PCNL 4.96 ± 1.21 days vs. FURSL 3.60 ± 0.83 days).

CONCLUSION

Both FURSL and PCNL were effective methods for treating upper ureteral stones of 1.5-2.0 cm in diameter given the extremely high stone clearance rate and a very low secondary surgery rate, as long as rare ureteral obstruction in medium-long term observation. Additionally, FURSL can effectively reduce surgical bleeding, postoperative pain, and hospital stay, while PCNL can decrease operation time, the risk of infection, and complications. Therefore, doctors could select suitable surgical treatment for those patients depending on their different clinical situations based on these findings.

Tubeless PCNL versus standard PCNL for the treatment of upper urinary tract stones: a propensity score matching analysis

PURPOSE

In this study, the feasibility of tubeless percutaneous nephrolithotomy (PCNL) for the treatment of upper urinary tract stones was investigated.

METHODS

From January 2021 to December 2022, the clinical data of 273 patients who received tubeless PCNL (Group A) were studied. The control group includes clinical data from 302 patients (from January 2019 to October 2022) who received standard PCNL (Group B). The baseline characteristics were consistent between the two groups after using the propensity score matching (PSM) method. Compare the preoperative clinical characteristics, postoperative complications, residual stones, catheterization time, and hospital stay between the two groups.

RESULTS

146 pairs of patients were successfully paired through PSM. There was no statistically significant difference in operative time, blood leukocyte counts, haemoglobin decrease, fever, urinary extravasation, sepsis, bleeding, blood transfusion rates, embolism, and residual stones after surgery between the two groups; Postoperative day 1 and discharge day, the VAS pain score in Group A was significantly lower than that in Group B. The catheterization time and hospitalization time of patients in Group A were significantly lower than those in Group B.

CONCLUSION

According to the inclusion and exclusion criteria, selecting suitable patients for tubeless PCNL is safe and effective, while significantly alleviating pain and reducing catheterization time and hospital stay.

Risk factors of high fluid absorption in patients treated with mini-PCNL: a single-center prospective study

BACKGROUND

The factors influencing fluid absorption in mini-percutaneous nephrolithotripsy (mini-PCNL) are still unknown. We aim to investigate the factors that influence irrigation fluid absorption during mini-PCNL.

METHODS

A total of 94 patients who underwent mini-PCNL were included in this prospective study. The endoscopic surgical monitoring system (ESMS) was used to measure the volume of irrigation fluid absorbed during the procedure. Irrigating time, the total volume of irrigation fluid, stone size, S.T.O.N.E. score, hemoglobin, electrolyte levels, and postoperative complications were recorded.

RESULTS

A significant correlation was observed between fluid absorption and the presence of postoperative fever, and based on this phenomenon, patients were divided into low and high fluid absorption groups. The serum creatinine level in the high fluid absorption group was significantly high (7 vs. 16.5, p = 0.02). Significant differences were observed between the low and high fluid absorption groups in terms of mean stone size (21.70 mm vs. 26.78 mm), presence of stone burden ≥ 800 mm2 (4% vs. 23%), S.T.O.N.E. score > 8 (4% vs. 38%), the fluid used > 18,596 ml (19% vs. 78%), irrigation time (55.61 min vs. 91.28 min), and perfusion rate (24% vs. 45%) (all p < 0.05). The rates of postoperative fever and SIRS in the high fluid absorption group were significantly high (p < 0.05).

CONCLUSIONS

Mean stone size, presence of stone burden ≥ 800 mm2, S.T.O.N.E. score > 8, the fluid used > 18596 mL, irrigation time, and perfusion rate are risk factors of intraoperative fluid absorption in mini-PCNL.

Percutaneous nephrolithotomy guided by 5G-powered robot-assisted teleultrasound diagnosis system: first clinical experience with a novel tele-assistance approach (IDEAL stage 1)

BACKGROUND

To demonstrate the technical feasibility of percutaneous nephrolithotomy (PCNL) guided by 5G-powered robot-assisted teleultrasound diagnosis system (RTDS) in a complex kidney-stone (CKS) cohort and present our preliminary outcomes. PCNL is highly skill-required, which hinders it popularization in primary medical units of remote regions. We designed an innovative tele-assistance approach to make PCNL easy to be operated by inexperienced surgeons.

METHODS

This was a prospective proof-of-concept study (IDEAL phase 1) on intraoperative tele-assistance provided by online urological experts via a 5G-powered RTDS. Total 15 CKS patients accepted this technology. Online experts manipulated a simulated probe to assist unskilled local operators by driving a patient-side robot-probe to guide and monitor the steps of access establishment and finding residual stones.

RESULTS

Median total delay was 177ms despite one-way network-connecting distance > 5,800 km. No perceptible delay of audio-visual communication, driving robot-arm or dynamic ultrasound images was fed back. Successful tele-assistance was obtained in all cases. The first-puncture access-success rate was 78.6% with a one-session SF rate of 71.3% and without complications of grade III-V.

CONCLUSIONS

The current technology based on 5G-powered RTDS can provide high-quality intraoperative tele-assistance, which has preliminarily shown satisfactory outcomes and reliable safety. It will break down a personal competence-based barrier to endow PCNL with more popular utilization.

TRIAL REGISTRATION

The study was approved by ethics committee of the Xinjiang Kezhou People's Hospital and ethics committee of the First Affiliated Hospital of Nanjing Medical University and was registered on http://www.chictr.org.cn (ChiCTR2200065849, 16/11/2022).

Effect of preoperative prophylactic antibiotic use on postoperative infection after percutaneous nephrolithotomy in patients with negative urine culture: a single-center randomized controlled trial

PURPOSE

To compare the effects of different preoperative antibiotic prophylaxis (ABP) regimens on the incidence of sepsis after percutaneous nephrolithotomy (PCNL) in patients with negative urine culture.

METHODS

A single-center, randomized controlled trial (June 2022-December 2023) included 120 patients with negative preoperative urine cultures for upper urinary tract stones who underwent PCNL (chictr.org.cn; ChiCTR2200059047). The experimental group and the control group were respectively given different levofloxacin-based preoperative ABP regimes, including 3 days before surgery and no ABP before surgery. Both groups were given a dose of antibiotics before the operation. The primary outcome was differences in the incidence of postoperative sepsis.

RESULTS

A total of 120 subjects were included, including 60 patients in the experimental group and 60 patients in the control group. The baseline characteristics of the two groups were comparable and intraoperative characteristics also did not differ. The sepsis rate was not statistically different between the experimental and control groups (13.3% vs.13.3%, P = 1.0). A multivariate logistic regression analysis revealed that body mass index (BMI) (OR = 1.3; 95% CI = 1.1-1.6; P = 0.003) and operating time (OR = 1.1; 95% CI = 1.0-1.1; P = 0.012) were independent risk factors of sepsis.

CONCLUSION

Our study showed that prophylactic antibiotic administration for 3 days before surgery did not reduce the incidence of postoperative sepsis in patients with negative urine cultures undergoing PCNL. For this subset of patients, we recommend that a single dose of antibiotics be given prior to the commencement of surgery seems adequate.

Efficacy of simultaneous bilateral surgery using the oblique overriding position in the treatment of bilateral kidney stones

To compare the safety and the efficacy of simultaneous bilateral surgery in the oblique overriding position versus staging surgery in the treatment of bilateral renal calculi. A total of 46 patients with bilateral renal stones from May 2019 to January 2022 in our center were retrospectively analyzed, including 29 males and 17 females, with a mean age of 48 ± 13.6 years, body mass index of 24.6 ± 2.3 kg/m2, and uneven size of bilateral renal stones, with a mean diameter of 29.5 ± 9.1 mm on the side with the larger kidney stones (PCNL) and a mean diameter of 13.1 ± 3.2 mm on the side with the smaller kidney stones. The patients were divided into two groups for simultaneous and stepwise bilateral endoscopic surgery, and the operative time, anesthesia time, postoperative hemoglobin, blood creatinine, postoperative VAS pain score, Clavien complication rating, average hospital stay, and stone removal rate at one month after surgery were evaluated in both groups. The simultaneous group outperformed the other group in anesthesia time, operative time, VAS score, and mean number of days in the hospital, and there were no significant differences between the two groups in postoperative hemoglobin drop values, hematocrit elevation values, Clavien complication ratings, and stone clearance rate at one month. Both simultaneous surgery and staging surgery were safe and effective. Simultaneous surgery can effectively shorten the operation and anesthesia time, and reduce the postoperative pain and hospital days of patients while ensuring similar stone clearance rates.

Chinese mini percutaneous nephrolithotomy for upper urinary calculi under local infiltration anesthesia

Percutaneous nephrolithotomy is generally performed under general or regional anesthesia; however, it is rarely performed under local infiltration anesthesia (LIA). This study aimed to assess the safety and effectiveness of Chinese mini percutaneous nephrolithotomy (MPCNL) for upper urinary calculi under LIA. A retrospective analysis of 52 patients with upper urinary stones who underwent MPCNL under LIA from April 2019 to May 2022 was performed. Pethidine and Phenergan were intramuscularly injected 30 minutes preoperatively. Oxybuprocaine hydrochloride gel was applied to the urethra for lubricating and mucosal anesthesia. Ropivacaine hydrochloride and lidocaine were injected into the whole percutaneous channel for local anesthesia. An 8/9.8F ureteroscope and an 18F vacuum-assisted access sheath were applied in MPCNL. All 52 patients tolerated procedures and underwent operations successfully; none of them converted the anesthesia method or required additional analgesia. The mean visual analogue scale scores intraoperatively and at 6 hours, 24 hours, and 48 hours after surgery were 3.25 ± 0.52, 3.13 ± 0.69, 2.25 ± 0.56, and 1.58 ± 0.50, respectively. The stone free rate was 84.6%. Complications were seen in 6 (11.5%) patients, including fever in 2 patients (Clavien I), renal colic in 1 patient (Clavien I), clinically insignificant bleeding in 2 patients (Clavien I), and urinary tract infection in 1 patient (Clavien II). No severe complications were observed in any patients. Chinese MPCNL under LIA was a feasible option and achieved good outcomes in appropriately selected patients, and it may become the routine procedure for general patients.

Percutaneous nephrolithotomy in patients with incidental encountered purulent urine at initial puncture

We are reporting the 39 patients' outcomes who underwent percutaneous nephrolithotomy and purulent urine encountered at the initial steps of surgery. Of 873 patients who underwent PCNL, 48 had purulent fluid during the initial puncture. After excluding those at risk for infection, we studied 39 patients' preoperative and postoperative variables-including postoperative day (POD) 1, 3, 5 fevers. In group 1, 21 patients had a nephrostomy tube placed, and PCNL was postponed. In group 2, 18 patients had successful stone removal in the first session. All surgeries were successful, with no septic events during follow-up. No significant differences in preoperative variables were found. 14% and 22% of patients in groups 1 and 2 had infected fluid (p = 0.470). Four patients in group 1 (19%) and seven patients in group 2 (38.9%) had a high fever (≥ 38 C) on POD1 (p = 0.171), and 1 (5%) in group 1 and 3 (17%) in group 2 had high fever on POD 3 (p = 0.22). No patients remained with high fever on POD5. Mild sepsis was diagnosed in 9.5% of group 1 and 16% of group 2 (p = 0.820), and hospitalization time differed significantly (p < 0.001). Stone size and operation time were correlated with postoperative fever, and prolonged hospital stays were associated with positive blood cultures and postponed procedures. PCNL with proper technique and antibiotics can lead to quicker recovery and reduced hospitalization time in selected patients with pus in their pelvicalyceal system.

Efficacy and safety of various endosurgical procedures for management of large renal stone: a systemic review and network meta-analysis of randomised control trials

Urolithiasis is the most common benign urological health condition. It has contributed sizeable burden of morbidity, disability, and medical health expenditure worldwide. There is limited high level of evidence on the efficacy and safety of treatment options of large renal stones. This network meta-analysis has examined the effectiveness and safety of various large renal stone management strategies. Systematic review and network meta-analysis (NMA) study design was employed to summarize comparative randomized controlled trials on humans with a diagnosis of renal stone larger than or equal to 2 cm in size. Our searching strategy was based on the Population, Interventions, Comparison, Outcomes, and Study (PICOS) approach. Medline via PubMed, Embase, Google scholar, SCOPUS, Science Direct, Cochrane library, Web of Science, and ClinicalTrials.gov were searched from inception to March 2023 to find eligible articles. Data extraction, screening, selection and risk of bias assessment were conducted by two independent reviewers. We found ten randomised control trials which consists 2917 patients, nine of them were labeled as low risk and one article was high risk. This network meta-analysis found that SFR was 86% (95% CI 84-88%) for Mini-PCNL, 86% (95% CI 84-88%) for standard PCNL, 79% (95% CI:73-86%) for RIRS, and 67% (95%CI:49-81 for staged URS for management of large renal stone. Overall complication rate was 32% (95% CI 27-38%) for standard PCNL, 16% (95% CI 12-21%) for Mini-PCNL, and 11% (95% CI 7-16%) for RIRS. Mini-PCNL (RR = 1.14 (95% CI 1.01-1.27) and PCNL (RR = 1.13 (95% CI 1.01-1.27)) were statistically associated with a higher SFR compared to RIRS. The pooled mean hospital stays were 1.56 days (95% CI 0.93-2.19) for RIRS, 2.96 days (95% CI 1.78-4.14) for Mini-PCNL, 3.9 days (95% CI 2.9-4.83) for standard PCNL, and 3.66 (95% CI 1.13-6.2) for staged URS. Mini-PCNL and standard PCNL were the most effective treatment options with significant morbidity and length of hospital stay, while RIRS was the safest management option with acceptable SFR, low morbidity, and short hospital stay.

Contrast-enhanced ultrasound versus conventional ultrasound-guided percutaneous nephrolithotomy in patients with a non-dilated collecting system: results of a pooled analysis of randomized controlled trials

BACKGROUND

Contrast-enhanced ultrasound in percutaneous nephrolithotomy (CEUS-PCNL) is an economical and practical technique for the treatment of patients with renal stones without significant collecting system dilatation. The aim of this systematic review is to compare the safety and efficacy of CEUS-PCNL and conventional ultrasound (US)-guided (US-PCNL) treatment of patients with renal calculi without significant hydronephrosis.

METHODS

This review was conducted with strict adherence to the PRISMA guidelines. Comparative studies on CEUS-PCNL and US-PCNL published in PubMed, SinoMed, Google Scholar, Embase, and Web of science until March 1, 2023, were systematically searched. RevMan 5.1 software was used for meta-analysis. Pooled odds ratios (ORs), weight mean differences (WMDs) and standard mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using the fixed-effects or random-effects model. Publication bias was evaluated using funnel plots.

RESULTS

Four randomized controlled trials involving 334 patients (168 with CEUS-guided PCNL and 166 with US-guided PCNL) were identified. There was no statistically significant difference between CEUS-guided PCNL and US-guided PCNL in terms of the operation time (SMD: - 0.14; 95% CI - 0.35 to 0.08; p = 0.21), minor complications (p = 0.48), major complications (p = 0.28) and overall complications (p = 0.25). However, CEUS-guided PCNL had a higher stone-free rate (OR: 2.22; 95% CI 1.2 to 4.12; p = 0.01), higher success rate of single-needle punctures (OR:3.29; 95% CI 1.82 to 5.95; p < 0.0001), shorter puncture time (SMD: - 1.35; 95% CI - 1.9 to - 0.79; p < 0.00001), shorter hospital stay (SMD: - 0.34; 95% CI - 0.55 to - 0.12; p = 0.002) and lesser hemoglobin loss (SMD: - 0.83; 95% CI - 1.06 to - 0.61; p < 0.00001) as compared with conventional US-guided PCNL.

CONCLUSIONS

According to almost all pooled data, CEUS-guided PCNL is superior to US-guided PCNL in terms of the perioperative outcomes. However, many rigorous clinical randomized controlled studies are required to obtain more accurate results. Registration The study protocol was registered with PROSPERO (CRD42022367060).

A randomized controlled study of ureteral stent extraction string on patient's quality of life and stent-related complications after percutaneous nephrolithotomy in the prone position

To demonstrate the Tianjin Institute of Urology (TJIU) technique to place and remove the ureteral stent with extraction string after percutaneous nephrolithotomy (PCNL). Additionally, we aim to compare the pain experienced during stent removal, quality of life during stent retention, and stent-related complications between patients with and without extraction string. 65 patients were included in the final analysis in the string group constructed by the TJIU technique and 66 patients in the conventional double-J ureteral stent (non-string) group. All patients underwent the surgery in a prone position under general anesthesia. They completed the Ureteral Stent Symptom Questionnaire (USSQ) on postoperative days (POD) 7, as well as before their ureteral stent was removed. The visual analogue scale (VAS) pain score (0-10) was completed immediately after the removal of the ureteral stent. Moreover, a specialized person was responsible for recording stent-related complications. All patients completed the USSQ on POD 7, and we did not find a difference in scores in each field. However, there was a significant difference in the "sex" domain before removing the ureteral stent (4.34 vs 3.23; p = 0.01). Notably, the use of extraction string after PCNL could decrease the pain associated with stent removal significantly (mean VAS scores 1.45 vs 2.76; p < 0.01). Extraction string did not increase the incidence of stent-related complications. We concluded that placing a ureteral stent with an extraction string after PCNL reduces the pain of ureteral stent removal without increasing complications such as accidental removal of the stent, febrile urinary tract infection (UTI).

Pattern of key opinion leaders talks at major international urological meetings reflects the main differences in flexible ureteroscopy and PCNL diffusion

OBJECTIVE

To analyze the pattern of speaker activity related to both flexible ureteroscopy (fURS) and percutaneous nephrolithotomy (PCNL) during plenary sessions at the main (endo)urological international meetings over the last 10 years.

METHODS

We reviewed the meeting programs of the main endourological international meetings (EAU, AUA, WCE, and SIU) during 2011-2019. We detected all invited speakers at plenary sessions regarding fURS or PCNL. The proportion of fURS and PCNL talks was evaluated yearly during the study period. In order to analyze plenary session speaker composition, we estimated and compared the mean number of talks per speaker according to surgical technique. We also analyzed possible differences in age distribution according to the topic of the talk as well as the presence of young (i.e., < 45 years) speakers. Data were analyzed using descriptive statistics.

RESULTS

During the last 10 years, a total of 498 plenary talks were found. Of those, 260 (52.2%), 211 (42.4%), and 27 (5.4%) discussed PCNL, fURS, or both, respectively. PCNL was more frequently discussed at the beginning and the end of the study period. Mean [SD] number of talks per speaker was higher for PCNL (2.9 [3.4] vs 1.6 [1.4], p < 0.001), meaning that a wider variety of speakers was invited to give fURS talks. Speakers discussing fURS were younger (median [interquartile range, IQR] age 48 [44-56] vs 52 [47-60] years, p < 0.001), and a higher proportion of young speakers was observed in the fURS group (26% vs 15% p < 0.001). PCNL speakers were more commonly discussing fURS than fURS speakers discussing PCNL (23% vs 17%, p = 0.43).

CONCLUSIONS

We found a wider variety of speakers at fURS plenary sessions as compared to PCNL ones. It is easier and quicker to become an internationally recognized expert in the field of fURS rather than PCNL. PCNL speakers were able to master fURS more frequently than the other way around.

International Alliance of Urolithiasis (IAU) Guideline on percutaneous nephrolithotomy

The International Alliance of Urolithiasis (IAU) would like to release the latest guideline on percutaneous nephrolithotomy (PCNL) and to provide a clinical framework for surgeons performing PCNLs. These recommendations were collected and appraised from a systematic review and assessment of the literature covering all aspects of PCNLs from the PubMed database between January 1, 1976, and July 31, 2021. Each generated recommendation was graded using a modified GRADE methodology. The quality of the evidence was graded using a classification system modified from the Oxford Center for Evidence-Based Medicine Levels of Evidence. Forty-seven recommendations were summarized and graded, which covered the following issues, indications and contraindications, stone complexity evaluation, preoperative imaging, antibiotic strategy, management of antithrombotic therapy, anesthesia, position, puncture, tracts, dilation, lithotripsy, intraoperative evaluation of residual stones, exit strategy, postoperative imaging and stone-free status evaluation, complications. The present guideline on PCNL was the first in the IAU series of urolithiasis management guidelines. The recommendations, tips and tricks across the PCNL procedures would provide adequate guidance for urologists performing PCNLs to ensure safety and efficiency in PCNLs.

Predictive value of CD3+ cells and interleukin 2 receptor in systemic inflammatory response syndrome after percutaneous nephrolithotomy

Objective

The aim of the current study was to evaluate the risk factors that influence the development of postoperative systemic inflammatory response syndrome (SIRS) after percutaneous nephrolithotomy (PCNL), including cytokines and lymphocyte subsets.

Methods

A total of 154 patients who underwent PCNL at our hospital between October 2019 and January 2022 were retrospectively reviewed. The development of post-PCNL SIRS was the primary endpoint of the study. Univariable analysis and multivariable logistic regression analysis were performed to identify independent risk factors of post-PCNL SIRS. A nomogram was constructed using the independent risk factors, and receiver operating characteristic (ROC) curves were drawn.

Results

There were 50 patients (32.5%) who developed SIRS after PCNL. In multivariate analysis, positive urine culture (odds ratio [OR], 3.556; p = 0.048), long operation time (OR, 1.011; p = 0.027), high IL-2R (OR, 1.002; p = 0.018), low percentage of CD3⁺ cells (OR 0.931; p = 0.006), and high white blood cell (WBC) count (OR, 1.282; p = 0.044) were independent risk factors for post-PCNL SIRS. These five significant variables were used to generate a nomogram that exhibited favorable fitting. The discrimination area under the ROC curves was 0.795.

Conclusions

Patients with long operation times, positive urine cultures, high interleukin 2 receptor, high white blood cell counts, and low percentages of CD3⁺ cells may be at a higher risk of developing SIRS after PCNL. In these patients, cautious and comprehensive preoperative evaluations and appropriate treatment strategies should be considered.

Totally X-ray-Free Ultrasound-Guided Mini-Percutaneous Nephrolithotomy in Galdakao-Modified Supine Valdivia Position: A Novel Combined Surgery

We introduced a novel surgery that combines ultrasound guidance, miniaturization and Galdakao-modified supine Valdivia (GMSV) position in percutaneous nephrolithotomy (PCNL) and evaluated the safety and efficacy. This retrospective, single-center study retrospectively reviewed 150 patients who underwent ultrasound-guided mini-PCNL in the GMSV position from November 2019 to March 2022. All perioperative parameters were collected. Stone-free status was defined as no residual stones or clinically insignificant residual fragments (CIRF) <0.4 cm on postoperative day one. Among the 150 patients, the mean age was 56.96 years. The mean stone size was 3.19 cm (427 mm2). The mean S.T.O.N.E. score was 7.61, including 36 patients (24%) with scores ≥9. The mean operative time was 66.22 min, and the success rate of renal access creation in the first attempt was 88.7%. One hundred and forty (93.3%) patients were stone free. The mean decrease in Hemoglobin was 1.04 g/dL, and no patient needed a blood transfusion. Complications included transient hematuria (n = 13, 8.7%), bladder blood clot retention (n = 2, 1.3%), fever (n = 15, 10%) and sepsis (n = 2, 1.3%). Totally X-ray-free ultrasound-guided mini-PCNL in the GMSV position is feasible, safe and effective for patients with upper urinary tract stones, indicating the synergistic and complementary effects of the three novel techniques.

Comparison of flexible ureteroscopy and mini-percutaneous nephrolithotomy in the treatment for multiple nephrolithiasis

Objective

To compare the outcomes of flexible ureteroscopy and mini-percutaneous nephrolithotomy in the treatment for multiple nephrolithiasis in 1–2 cm size.

Methods

The clinical data of patients with multiple renal calculi in the range of 1–2 CM who underwent flexible ureteroscopy lithotripsy and percutaneous nephrolithotomy in Qilu Hospital of Shandong University from January 2016 to March 2021 were retrospectively collected and matched using propensity score matching. Then a subgrouping of the number of stones was performed. Patients were divided into Group A and Group B according to their stone numbers. Patients with no statistically significant differences in baseline data were matched to compare the safety and efficacy of the two procedures.

Results

A total of 210 patients with clinical data were collected, and the patients’ baseline data were not comparable, and 142 patients were finally included in the study after propensity score matching. There was no statistical difference in baseline data between the two groups of patients. The postoperative hospital days (3.00, 2.00 vs. 7.00, 3.00, P < 0.001), operation time (90.00, 50.00 vs. 110.00, 53.00, P = 0.018), complications (6, 6.8% vs. 14, 25.9%, P = 0.001) of patients in flexible ureteroscopy group %, P = 0.001) was significantly lower than that in the percutaneous nephrolithotomy group. There was no significant difference in stone clearance rate between the two groups (76, 86.4% vs. 42, 77.8%, P = 0.185). When the number of stones was no more than 3, the operation time (85.00, 49.00 vs. 110.00, 53.00, P = 0.005) and complications (2, 4.2% vs. 11, 29.7%, P = 0.001) of f-URS were significantly less than those of mPCNL, but when the number of stones was more than 3, there was no significant difference between the two operations.

Conclusion

For multiple nephrolithiasis within 1–2 CM, when the number of stones does not exceed 3, flexible ureteroscopy can achieve the same stone clearance rate as percutaneous nephrolithotomy, while having shorter post-operation days, operative time and fewer complications. When the number of stones is more than 3, there are no significant difference between two operations.

Ultrasound-Guided Mini Percutaneous Nephrolithotomy with Suction Sheath

The mini percutaneous nephrolithotomy (PCNL) is a mainstay in the treatment of kidney calculi, particularly in case of >2 cm kidney stones, large lower pole stones, large impacted proximal ureteral stones, and residual stones after failed extracorporeal shockwave lithotripsy or retrograde intrarenal surgery. An accurate renal access represents a fundamental part of the procedure, modalities to guide the percutaneous tract preparation include ultrasound, fluoroscopy, or their combination. Both ultrasound and fluoroscopy offer several advantages and some limitations. The combined utilization of ultrasound and fluoroscopy is less adopted nowadays; however, this strategy has its merits particularly in cases where the puncture can be problematic with one imaging modality alone. Ultrasound can easily identify the posterior renal calix and surrounding visceral structures, although some situations such as obese patients, undilated collecting system or complex stones may represent a challenge. Intracaliceal blood clots and air may reflect ultrasound, reducing significantly the image quality. Therefore, the assessment of the intrarenal anatomy, the stone identification, and the ability of guiding the needle during access may decrease significantly, particularly in cases with complex stones, when multiple tracts are required. In these cases, fluoroscopy could determine the relationship between the angle and depth of the puncture needle and the target calices by rotating the C-arm to help the needle puncture and tract dilation. Therefore, the benefits of dual guidance would be beneficial during PCNL. In addition to an improved accuracy of puncture and dilation, the combined approach improves the detection of residual stones, facilitating the achievement of a stone-free state. Herein we describe our experience with this technique, describing surgical steps and troubleshooting tips of mini-PCNL in the accompanying video. Further high-quality studies are needed to demonstrate the advantages of combined utilization of ultrasound and fluoroscopy during PCNL and its optimal indications.

Access and Fluoroscopy Time Difference in Patients Undergoing Prone Percutaneous Nephrolithotomy (PCNL) With Ureteric Catheter Placement in Supine Versus Lithotomy Position

Objective: To compare the operative and fluoroscopy time in two different methods of ureteral stent insertion before prone percutaneous nephrolithotomy (PCNL).

Materials and method: Over 12 months, 124 patients with urolithiasis who went through prone PCNL were included in our study. All the patients had kidney stones and were divided into two groups based on the method of ureteral catheter insertion. This was done with the help of flexible or rigid cystoscopy in to group A and group B, respectively. Both groups had an equal number of patients, i.e., 62. The main outcome variables assessed were access time (from intubation to placement of access sheath) and fluoroscopy time during access.

Results: The categorical variables (age, gender, site of the stone) between the two groups were comparable. The access time in groups A and B were 48±4.30 and 77±10 minutes, respectively. The fluoroscopy times in groups A and B were 52±14.63 and 116±47.77 seconds, respectively. A statistically significant difference (p-value < 0.05) was observed for both the access and fluoroscopy time. None of the patients in either of the groups had a misplaced ureteral catheter requiring repositioning.

Conclusion: Flexible cystoscope-assisted insertion of ureteral catheter prior to PCNL significantly reduces operative time, fluoroscopy time, and consequently radiation exposure during PCNL.

3D Imaging Segmentation and 3D Rendering Process for a Precise Puncture Strategy During PCNL – a Pilot Study

Percutaneous nephrolithotomy (PCNL) is frequently used as the first-line treatment of large and complex stones. The key point for successful complex stone removal with minimal risk of complications is to establish the most appropriate access route. Understanding the three-dimensional (3D) relationship of kidney stones and renal collecting systems is crucial for planning and creating an optimal access route. By using a 3D volume segmentation tool a more accurate approach to the renal collecting system and stone treatment could be planned. The objective of this study was assessing the impact of 3D software in getting the desired access.

RISK OF OCCURRENCE AND WAYS TO IMPROVE THE TREATMENT OF UROLITHIASIS IN PATIENTS WITH A SINGLE KIDNEY

OBJECTIVE

The aim: To summarize the state of the problem of urolithiasis in patients with a single kidney and consider current views on improving its treatment based on the analysis of world literature.

PATIENTS AND METHODS

Materials and methods: The study conducted a thorough analysis of modern scientific literature sources in the international scientometric database, which highlighted the development of urolithiasis in patients with a single kidney and the peculiarities of its treatment. The main ways to improve treatment are identified. A critical assessment of the achievements and shortcomings of various surgical treatments. The authors' own developments are presented in the article.

CONCLUSION

Conclusions: The topographic position of the kidney in the retroperitoneal space affects not only the occurrence of pathological processes in the kidney, but also the surgical strategy in the treatment of nephrolithiasis. Percutaneous nephrolithotomy is the main treatment for large (> 2 cm) or complex kidney stones. Patients with a single kidney are more prone to bleeding with PCNL treatment than patients with bilateral kidneys because they have an increased thickness of the renal parenchyma as a result of compensatory hypertrophy. RIRS is a reliable choice for patients with a single kidney who is contraindicated in PCNL.