Innovations in percutaneous nephrolithotomy

Therapeutic experience and key techniques of tubeless percutaneous nephrolithotomy

The tubeless percutaneous nephrolithotomy (PCNL) is highly favored by endourological urologists for its advantages in patient experience and length of hospital stay. However, there is currently no guideline or consensus that precisely describes tubeless PCNL. This study explores tubeless PCNL from two aspects: patient selection and technical improvements. Clinical data of 40 cases of conventional PCNL and tubeless PCNL patients operated by the same surgeon between December 2023 and April 2024 were analyzed. The changes in the preoperative and postoperative renal function, hemoglobin and inflammatory markers were evaluated, and the operative time, pain scores, and length of hospital stay were also included. Both groups of patients achieved complete stone clearance (100%). Compared to the conventional PCNL group, the tubeless PCNL group had lower pain scores (P < 0.001) and shorter hospital stays (P = 0.005). There were no statistically significant differences between the two groups in terms of operative time (P = 0.83), renal functional impact (P = 0.699), hemoglobin reduction (P = 0.93), and changes in inflammatory markers (P > 0.05). Tubeless PCNL demonstrated better patient experience and shorter hospital stays. Tubeless PCNL patients were strictly selected according to our criteria and operated based on traditional experience and the improved technical standards in this study. Tubeless PCNL is safe and feasible under these conditions. Retrospectively registered: 0620, August, 2024.

Comparative Outcomes of Day-case Percutaneous Nephrolithotomy Versus Conventional Inpatient Surgery: A Systematic Review and Meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis to evaluate the effectiveness and safety of PCNL performed as a day-case surgery in comparison to inpatient PCNL.

METHODS

Databases were searched up to January 27, 2024, for randomized and non-randomized studies comparing outcomes between day-case PCNL and inpatient PCNL. Pooled data were analyzed using a random-effects (RE) model when Higgins I2% heterogeneity values were >50%; otherwise, a fixed-effects model was employed. The results were reported as odds ratios (OR), mean difference (MD) or standardized MD (SMD) with 95% confidence intervals (CI). Statistical significance was set at P <.05.

RESULTS

One randomized controlled trial (RCT) and 14 observational studies totaling 1574 patients were included. Pooled results revealed that patients in the day-case PCNL group experienced reduced blood loss (SMD -0.71 95% CI: [-1.31, -0.12] P .02) and transfusion rates (OR 0.10 95% CI: [0.03, 0.39], P .0008), lower overall and minor complications (OR 0.56, 95% CI: [0.42, 0.76], P .0002, and OR 0.52, 95% CI: [0.37, 0-73], P .0002, respectively), shorter operative time (MD -11.46, 95% CI: [-17.41, -5-50], P <.00001), and reduced total costs (MD -1597.18, 95% CI [-2436.42, -757.93], P .0002). Major complications, stone-free rate (SFR), emergency department (ED) visits, and readmission rates were similar between the groups.

CONCLUSION

Day-case PCNL is a feasible and safe alternative to inpatient PCNL surgery in carefully selected patients, without increasing the risk of complications or readmission rates, and is likely to reduce total costs.

Mini percutaneous nephrolithotripsy for pediatric kidney stone using 1.5mm probe size shock pulse lithotriptor: A case report

The recent development of mini-PCNL technique, allows tract formation with minimal damage to the renal parenchyma in pediatric patients. This report describes our preliminary findings with mini-PCNL using a 1.5-mm probe-size shock pulse lithotriptor. A 11-year-old child presented with multiple small inferior calyceal calculi. The patients were placed in Bartz flank-free modified supine position and underwent mini PCNL. The stone was fragmented using a 1.5-mm probe shock pulse lithotripter and fragments were suctioned out through the hollow probe. Our experience suggests that using a shock pulse lithotripter on a mini-PCNL to treat renal stones in children is both safe and effective.

Worldwide practice patterns of percutaneous nephrolithotomy

PURPOSE

To evaluate the current practice of percutaneous nephrolithotomy (PCNL), conducting a worldwide survey among urologists with a special interest in endo-urology.

METHODS

A 22-question survey was specifically developed by the European Association of Urology (EAU) young academic urologists (YAU) and uro-technology (ESUT) groups and globally distributed via SurveyMonkey to almost 2000 members of Endourology Society. The questionnaire included questions dedicated to the demographics and general practice of the participating urologists.

RESULTS

In total, 441 responses (male/female ratio - 418/23) were received. A comparatively higher percentage of specialists (56.2%) practiced in academic institutions and had specific endo-urological fellowship training (56.7%). The classical prone PCNL remained the most practiced approach among the surveyed specialists, 47.7% stated to always do prone PCNLs, while 51.8% of respondents used multiple positioning options as required. The PCNL tract was mostly performed by urologists (84.3%) and fluoroscopic guidance was still predominantly used by 74.5% of respondents. The most practiced tract dilation method was balloon dilator used by 42% of respondents. Most of the surveyed urologists had ultrasonic, pneumatic or laser lithotripsy devices in their armamentarium. The use of some form of post-procedural drainage was reported in 85.1% of respondents, whereas tubeless PCNL remained a fairly uncommon practice.

CONCLUSION

The majority of urologists still use prone positioning, get their own access under fluoroscopy guidance and use a balloon for tract dilation. However, we also identified that when necessary, urologists will deviate from routine practice and change strategy, adopting other approaches for PCNL.

Rigid ureteroscopic lithotripsy in the lateral decubitus position for upper urinary tract stones

Background

The current study aimed to assess a novel ureteroscopic technique developed for treating upper urinary calculi based on a specially designed lateral decubitus body position that could avoid stone loss by adjusting to the effects of gravity.

Methods

This retrospective study examined patients with upper urinary calculi who were surgically treated from November 2008 to January 2020, using a new body position and a rigid ureteroscope. Clinical outcomes, stone-free rates, operative times and complications were evaluated, and factors that could influence treatment success were determined.

Results

In total, 1080 patients were included, and 1145 operations were performed. The maximum calculus diameters were 11.22 ± 5.01 mm. Operative times were 48.60 ± 27.44 min. A total of 1042 cases were successfully treated, with a stone-free rate of 91.00%. Multivariate analysis showed that female sex (OR = 2.135, 95% CI 1.332–3.422, P = 0.002), thin scope standby (OR = 1.643, 95% CI 1.074–2.514, P = 0.022), laser lithotripsy (OR = 5.087, 95% CI 2.400–10.785, P = 0.000) and stone size (OR = 0.946, 95% CI 0.912–0.981, P = 0.003) were independently associated with stone-free outcomes. In total, 2 ureteral perforations, 2 ureteric avulsions and 4 urosepsis cases were observed, but were all cured without sequelae.

Conclusions

Ureteroscopic lithotripsy in the lateral decubitus position is a safe and effective technique for treating upper urinary tract calculi, especially upper ureteral calculi.

Technical aspects to maximize the hyperaccuracy three-dimensional (HA3D™) computed tomography reconstruction for kidney stones surgery: a pilot study

The aim of the current prospective pilot study was to describe a hyperaccuracy three-dimensional (HA3D^™) model reconstruction technique, specifically developed to maximize the visualization of the renal collecting system's anatomy, and its relationship with the stones, vessels and renal parenchyma, and to compare the HA3D^™ virtual models with the intraoperative findings. The image acquisition was performed using a CT scanner (Toshiba, Aquilion Prime) and included the unenhanced, arterial, venous and excretory phases. The DICOM format CT images were processed by MEDICS Srl ( www.medics3d.com , Turin, Italy). In total, study included three patients with renal stone scheduled for non-papillary prone percutaneous nephrolithotomy (PCNL). The median age and BMI were 51 (range 49-54) and 25.5 (range 25.0-32.7), respectively. The median stone size was 1170 mm² (range 830-1520) and median stone density was 1130 HU (range 600-1340). In all cases, the quality of the CT images acquired with our protocol was adequate to perform the HA3D^™ reconstruction. Median operative and puncture time were 39.4 (range 35.2-44.0) and 1.9 (range 1.8-2.1) mins, respectively. The success rate for the first attempt of the percutaneous puncture was 100%, and only one PCNL tract was sufficient to complete the surgery. All three patients were stone-free on the third postoperative day. A dedicated imaging acquisition protocol and a tailored 3D model reconstruction process specifically developed for kidney stones treatment allow obtaining HA3D^™ highly relevant models to greatly match intraoperative findings during PCNL with the potential of minimizing bleeding and organ injury complications.

The Pattern of Day Case (Ambulatory) Percutaneous (PCNL): A Descriptive Retrospective Study from a Tertiary Care Hospital

Background: Percutaneous nephrolithotomy (PCNL) has experienced remarkable development and alteration since it was first described in 1976 by Fernstorm et al. It has also experienced miniaturization of equipment, improvement in operative systems, and refining renal access methods leading to the achievement of maximum clearance of stone while causing minimal morbidity. For example, in endourological practice, when the patient is subjected to PCNL, he traditionally needs programmed inpatient admission, as part of their recovery, it is applicable as an outpatient method in properly selected cases. Objectives: We aimed at evaluating the safety and applicability of the outpatient PCNL procedure. Methods: This retrospective study was done on 210 cases of tubeless PCNL performed by a single urologist at our institute from January 2016 to January 2019. Patients’ mean age (134 males and 76 females) was 57 ± 11.8 years, and 7 patients aged 8 - 12 years. There were 71 pelvic or calyceal solitary stones, 62 non-complete staghorn stones, 17 ureteral stones, 32 renal + ureteric stones (simultaneous renal and ureteral stones) , and 28 complete staghorn stones. The average stone size was 3.5 ± 2.8 (range: 0.7 to 11.8 cm). Results: The mean operation duration was 85.0 ± 29.4 min, and the mean hospital stay was 21.7 ± 3.4 h. Out of 210 patients, 6 patients had longer stay due to high-grade fever and 3 patients due to severe pain, and also 7 patients refused discharge due to personal and social reasons. Our ambulatory PCNL rate was 97 % ( 194 out of 210). Within 72 h, 5 patients were readmitted due to high-grade fever, 3 patients due to haematuria, and 4 patients due to pain and dysuria, and all patients were discharged 2 - 4 days after conservative treatment. Thus, the readmission rate was 6.18% (12 cases were readmitted out of 194 cases). Patients showed a blood transfusion rate of 1.4 %. Also, 19 cases (9.02%) were found with post-operative fever, and no urosepsis was reported. No pulmonary complications and mortality were noted. No re-exploration was done, and no major leak was noted. The angio-embolization rate was 0.59%. We did not use HEMO-SEAL technology, cautery, or suture in the tracks. Conclusions: In conclusion, the outpatient PCNL procedure is an applicable and feasible procedure under selected criteria; however, more investigations using a larger sample size are needed.

The First Case Report of Robot-Assisted Fluoroscopy-Guided Renal Access During Endoscopic Combined Intrarenal Surgery

Background: During percutaneous nephrolithotomy (PCNL) and endoscopic combined intrarenal surgery (ECIRS), obtaining renal access is the most critical step to achieving effective treatment without major intraoperative complications. Among a variety of methods attempted to improve the access, robot-assisted fluoroscopy-guided (RAFG) renal access has been introduced to mitigate technical human errors and overcome challenging learning curves. In this study, we present our first experience with an automated needle targeting with an X-ray (ANT-X) device for minimally invasive (mini-) ECIRS. Case Presentation: A 75-year-old healthy woman with a 6.0 cm³ left kidney stone was referred to our hospital for surgical treatment. The patient underwent mini-ECIRS utilizing RAFG renal access without complication, and the stone was completely removed. The ureteral stent and transurethral catheter were removed on postoperative day 2, and the patient was discharged on postoperative day 3. There were no residual fragments detected by CT as of 3 months after the surgery. Conclusion: To our knowledge, this is the first report of the effective use of RAFG mini-ECIRS for a kidney stone. The overall outcome was positive, indicating the feasibility of ANT-X use for PCNL and ECIRS.

Ultra-mini flexible percutaneous nephrolithotomy in the treatment of moderate-size kidney stones: a new instrument, a preliminary prospective study

Ultra-mini PNL is increasingly preferred in the treatment of kidney stones. Unlike routine applications of the ultra-mini PNL technique, we aimed to perform kidney stones treatment with an epiduroscopic device that can pass through 11-13-Fr ureteral access sheaths with a flexible structure and which is routine in neurosurgical practice. The study was planned prospectively. The study included 52 patients with mid-sized kidney stones who had presented to our clinic between July 2017 and January 2019. The ultra-mini percutaneous nephrolithotomy was carried out with epiduroscopy routinely used in neurosurgery practice, which can pass through 11-13-Fr ureteral access and has a flexible structure. The perioperative and postoperative parameters were analyzed. The mean operation time was 45.6 ± 4.8 min and entry was provided through a single entry (from the calyx appropriate to the lower pole) in all patients; a second entry tract was not required. No DJ catheter or nephrostomy tube was installed in any patient and the procedures were completed totally without a tube. The mean reduction in hemoglobin values was determined as 0.33 (0.1-1.1) g/dL. None of the patients needed transfusion and no patient developed acute kidney injury. Clinically significant (≥ 3 mm) residual stone was observed in 2 (4%) of the 52 patients, while clinically insignificant (≤ 3 mm) stones were observed in 50 patients (96%). The mean length of hospital stay was 2.5 ± 0.9 days. Ultra-mini flexible percutaneous nephrolithotomy is an effective and safe method in the treatment of medium-sized kidney stones.

Comparison of the efficacy and safety of shockwave lithotripsy, retrograde intrarenal surgery, percutaneous nephrolithotomy, and minimally invasive percutaneous nephrolithotomy for lower-pole renal stones: A systematic review and network meta-analysis

BACKGROUND

Shock wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and minimally invasive PCNL are currently therapeutic options for lower-pole renal stones (LPS). However, the optimal treatment for LPS remains unclear. A comprehensive evaluation of the efficacy and safety of each intervention is needed to inform clinical decision-making. This study aimed at assessing the efficacy and safety of different interventions for LPS.

METHODS

PubMed, Embase, ScienceDirect, ClinicalKey, Cochrane Library, ProQuest, Web of Science, and ClinicalTrials.gov were searched from inception to December 6th 2018. Only randomized controlled trials (RCTs) including the patients treated for LPS were included. The frequentist models of network meta-analysis were used to compare the effect sizes. The primary outcome was stone free rate, and the secondary outcomes were overall complication rate, major complication rate, retreatment rate, and auxiliary procedure rate.

RESULTS

This study included 13 RCTs comprising 1832 participants undergoing 6 different interventions, including RIRS, PCNL, Mini-PCNL, Micro-PCNL, SWL, and conservative observation. PCNL had the best stone free rate (odds ratio [OR] = 3.45, 95% confidence interval [CI] = 1.30-9.12), followed by Mini-PCNL (OR = 2.90, 95% CI = 1.13-7.46). Meta-regression did not find any association of the treatment effect with age, sex, and stone size. Although PCNL tended to exhibit a higher complication rate, the difference of complication rate among various interventions did not achieve a statistical significance. SWL was the less effective and associated with higher retreatment rate compared with PCNL, Mini-PNCL, and RIRS.

CONCLUSIONS

PCNL was associated with the best stone free rate for LPS regardless of age, sex, and stone size. Each treatment achieved a similar complication rate compared with the others. Future large-scale RCTs are warranted to identify the most beneficial management for renal stones at a more complicated location.

Safety and Efficacy of Day-case Percutaneous Nephrolithotomy: A Systematic Review from European Society of Uro-technology

CONTEXT

Day case or ambulatory percutaneous nephrolithotomy (PCNL) has risen over the last few years with the aim of discharging patients within 24h.

OBJECTIVE

We perform a systematic review of literature to evaluate the outcomes of day-case PCNL surgery.

EVIDENCE ACQUISITION

A Cochrane style search was performed and the following bibliographic databases were accessed: PubMed, Science Direct, Scopus, and Web of Science. This was carried out in accordance with the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. All studies in the English language reporting on PCNL patients discharged within 24h were included.

EVIDENCE SYNTHESIS

Based on the literature search of 97 articles, nine (502 patients) met the inclusion criteria (mean age: 47 yr), with a mean stone size of 20.5mm. The mean operating time was 66min, and over a mean hospital stay of 17.5h, the stone-free rate was 95%. The overall complication rate was 13.5%; the vast majority of these complications were Clavien I-II complications, with a readmission rate of 3%.

CONCLUSIONS

Day-case PCNL is a safe and feasible strategy in carefully selected cases. However, for its success, detailed planning and adherence to surgical protocol are paramount with strict criteria for inpatient admission and a thorough follow-up plan.

PATIENT SUMMARY

Day-case percutaneous nephrolithotomy procedure seems to be a safe procedure with good outcomes, and low risk of complications and readmissions. Detailed preoperative protocol and planning are paramount, with indications for inpatient admission as well as a thorough follow-up plan.

Updates in endourological management of urolithiasis

Urinary stone disease, or urolithiasis, is a very common disease with increasing prevalence and incidence. With the advancement of endoscopic techniques, the treatment outcomes of ureteroscopy (or transureteral lithotripsy) and percutaneous nephrolithotomy are continuously improving. In recent years, there have been many new developments in the field, including new endoscopy design, more effective auxiliary tools, improvement in treatment protocols, introduction of robotic technology, combining both ureteroscopy and percutaneous nephrolithotomy (endoscopic combined intrarenal surgery or transureteral lithotripsy-assisted percutaneous nephrolithotomy), improvement in laser technology, and so on. All these new inputs will further improve the treatment efficacy and safety of the procedures, thus benefiting our patients. In the present review, we briefly go through the main steps of ureteroscopy and percutaneous nephrolithotomy, with a concise description and application of these new advances.