Percutaneous-based management of Staghorn calculi in solitary kidney: combined mini percutaneous nephrolithotomy versus retrograde intrarenal surgery

2022 Recommendations of the AFU Lithiasis Committee: Specific cases - chronic kidney disease, bilateral stones, and solitary kidney

Chronic kidney disease, diabetes and hypertension are risk factors of kidney function impairment. The relative risk of kidney failure is 1.52 in patients with urinary stone disease. The various techniques used to remove upper urinary tract stones generally do not alter kidney function in patients with normal kidney function and may sometimes improve kidney function or slow its deterioration in patients with kidney disease. Compared to the asynchronous treatment of bilateral renal and ureteral stones, concomitant treatment is associated with higher risk of anuria and the need of additional interventions, in the absence of postoperative stenting. For the treatment of solitary kidney stones, the absence of postoperative stenting increases the risk of postoperative anuria. Moreover, the multiplication of percutaneous nephrolithotomy access tracts increases the risk of bleeding and that of kidney function impairment. METHODOLOGY: These recommendations were developed according to two methods: the Clinical Practice Recommendations (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 Guidelines on urolithiasis. 2022] and their adaptability to the French context.

Comparison of mini endoscopic combined intrarenal surgery and multitract minimally invasive percutaneous nephrolithotomy specifically for kidney staghorn stones: a single-centre experience

BACKGROUND

Staghorn stones require surgical treatment to prevent serious complications. Multitract percutaneous nephrolithotomy (PNL) causes great renal parenchymal injury and blood loss. One-stage endoscopic combined intrarenal surgery (ECIRS) entails the combined use of antegrade nephroscope and retrograde flexible ureteroscope to clear the staghorn stone, which may overcome the limitations of multitract PNL. We aimed to compare the perioperative outcomes of mini ECIRS and multitract minimally invasive PNL in staghorn stone management.

METHODS

This was a retrospective single-center study of patients with staghorn stones who underwent ECIRS (n = 17) or multitract minimally invasive PNL (n = 17) between January 2018 and September 2021.

RESULTS

There was a significant between-group difference with respect to Guy's stone score. Stone size, stone burden (ECIRS group, 21.41 cm3; multitract minimally invasive PNL group, 20.88 cm3 [P = 0.94]), and degree of hydronephrosis were comparable in the two groups. There was no significant between-group difference with respect to one-step or final stone-free rates. The mean operative time was also not significantly different between the groups (ECIRS group, 140 min; multitract minimally invasive PNL group, 183 min [P = 0.63]). ECIRS was associated with significantly lesser postoperative pain (visual analog scale; ECIRS group: 0; multitract minimally invasive PNL group: 2.7 [P < 0.001]). Hemoglobin loss, postoperative blood transfusion rate, complications, and length of hospital stay were comparable in the two groups.

CONCLUSION

Both mini ECIRS and multitract minimally invasive PNL were effective and safe for the management of renal staghorn stones with comparable operation time and stone-free rate, and complications. ECIRS was associated with less severe postoperative pain.

A novel approach in creating nephrostomy using a double-lumen access sheath during endoscopic combined intrarenal surgery

Background

This study aimed to evaluate the safety and efficacy of an inner ureteral access sheath (i-UAS) with a double-lumen channel used in ureteroscopic lithotripsy (URS) as a dilator for the percutaneous tract in endoscopic combined intrarenal surgery (ECIRS).

Methods

This was a single-center cohort study conducted from January 2016 to April 2020. We used an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during the creation of the nephrostomy tract in ECIRS. Univariate and multivariate analyses were performed to assess the association between the perioperative parameters and the use of i-UAS. The primary endpoint was perioperative complications, and secondary endpoints were stone-free rate (SFR), operative time, fluoroscopy time, and duration of hospitalization.

Results

In total, 221 patients were enrolled during the study period. Patients were divided into an i-UAS dilation group (n=108) and a one-shot dilation group (n=113). No differences were observed between the two groups in terms of patient history. Univariate analyses indicated that, in the i-UAS dilation group, the operative time was shorter [105.50 (83.75–143.25) vs. 121.00 (90.00–155.00) min; P=0.02] and the modified Valdivia position was more frequently selected. Multivariate analyses showed no significant differences in the frequency of complications, such as urinary injury or postoperative pyelonephritis, but it showed a significantly shorter operative time as well as fewer tract creation troubles in the i-UAS dilation group.

Conclusions

Using an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during ECIRS is a convenient and safe technical method for creating a nephrostomy tract that can reduce the operative time.

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

CONTEXT

Although percutaneous nephrolithotomy (PCNL) has been performed for decades and has gone through many refinements, there are still concerns regarding its more widespread utilization because of the long learning curve and the potential risk of severe complications. Many technical details are not included in the guidelines because of their nature and research protocol.

OBJECTIVE

To achieve an expert consensus viewpoint on PCNL indications, preoperative patient preparation, surgical strategy, management and prevention of severe complications, postoperative management, and follow-up.

EVIDENCE ACQUISITION

An international panel of experts from the Urolithiasis Section of the European Association of Urology, International Alliance of Urolithiasis, and other urology associations was enrolled, and a prospectively conducted study, incorporating literature review, discussion on research gaps (RGs), and questionnaires and following data analysis, was performed to reach a consensus on PCNL.

EVIDENCE SYNTHESIS

The expert panel consisted of 36 specialists in PCNL from 20 countries all around the world. A consensus on PCNL was developed. The expert panel was not as large as expected, and the discussion on RGs did not bring in more supportive evidence in the present consensus.

CONCLUSIONS

Adequate preoperative preparation, especially elimination of urinary tract infection prior to PCNL, accurate puncture with guidance of fluoroscopy and/or ultrasonography or a combination, keeping a low intrarenal pressure, and shortening of operation time during PCNL are important technical requirements to ensure safety and efficiency in PCNL.

PATIENT SUMMARY

Percutaneous nephrolithotomy (PCNL) has been a well-established procedure for the management of upper urinary tract stones. However, according to an expert panel consensus, core technical aspects, as well as the urologist's experience, are critical to the safety and effectiveness of PCNL.

Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy

PURPOSE OF REVIEW

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

RECENT FINDINGS

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal. Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.

A comparative study of endoscopic combined intrarenal surgery (ECIRS) in the galdakao-modified supine valdivia (GMSV) position and minimally invasive percutaneous nephrolithotomy for complex nephrolithiasis: a retrospective single-center study

The aim of this research is to compare the efficiency and safety between endoscopic combined intrarenal surgery (ECIRS) in the Galdakao-modified Supine Valdivia (GMSV) position and minimally invasive percutaneous nephrolithotomy (Mini-PCNL) in a single session for the treatment of complex nephrolithiasis. 140 consecutive patients who were diagnosed with multiple pyelocaliceal stones or staghorn renal calculi were enrolled and reviewed retrospectively. Demographic, clinical information and surgical outcomes were collected and analyzed. Demographic variables and stone characteristics did not show statistically differences. Over 80% of the patients were diagnosed with multiple pyelocaliceal stones, while the remainders were branched renal calculi. Over half of the patients were classified into medium and high Seoul National University Renal Stone Complexity scoring system (S-ReSC) score groups. The stone free rate (SFR) in the single session was significantly higher in the ECIRS group than in the Mini-PCNL group (88.06% vs. 66.67%, P = 0.003). The subgroup analysis revealed that ECIRS was more efficacious than Mini-PCNL for complex renal calculi with medium and high S-ReSC scores (P = 0.002). A nonsignificant but relatively lower postoperative complication rate was noted in the ECIRS group (7.5 vs. 16.0%, P = 0.12). With the exception of postoperative hospitalization days (P < 0.001), significant difference was not detected between the two groups for other procedure-related information. ECIRS in the GMSV position is an effective and safe treatment especially for medium and severe complex nephrolithiasis, with significant higher SFR in the single session and relatively low procedure-associated morbidity compared to Mini-PCNL.

Early experience of Retrograde Intrarenal Surgery for Renal stone: A Descriptive Cross-sectional Study

Introduction:

Retrograde intrarenal surgery with improving skill and knowledge may be considered one of the first-line treatment options for removal of renal stones. The study is done to find the outcome of retrograde intrarenal surgery (RIRS) in patients with renal stone.

Method:

This descriptive cross sectional study was carried out on patients undergoing retrograde intrarenal surgery for renal stone at a tertiary care hospital December 2019 to March 2020. Ethical approval was taken from the institutional review committee (Ref. no.200120202). The Convenient sampling method was applied. Data was collected and analyzed in Statistical Package for the Social Sciences version 20.0. Point estimate at 95% confidence interval was calculated along with frequency and proportion for binary data.

Results:

Out of the 28 patients, the retrograde intrarenal surgery was successful in 27 (96.4%) cases. There were 16 (57.15%) females and 12 (42.86%) male patients with the mean age of 37.86±11.47 years. Most of the stones were in renal pelvis 18 (64.28%) followed by lower calyx 8(28.57%). The mean diameter of the stone was 11.47±3.33mm whereas most of the stones were on the right side 16 (57.15%). The mean hardness was 1155.21±265.34 Hounsfield units. Perioperative complications like failed access sheath placement in 2 (7.14%) cases, hematuria in 6 (21.43%) cases, fever in 6 (21.43%) cases, and septicemia in 4 (14.28%) cases.

Conclusions:

We found that the success rate of retrograde intrarenal surgery for the renal stone was acceptable and similar to other published studies . Retrograde intrarenal surgery is feasible for the treatment of kidney stones with acceptable complications and success rates.

The role of ureteroscopy for treatment of staghorn calculi: A systematic review

Objective

To define the role of ureteroscopy for treatment of staghorn calculi.

Methods

A systematic review was conducted using the Scopus and Medline databases. Original articles and systematic reviews were selected according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only studies relating to the role of ureteroscopy for treatment of staghorn calculi were included.

Results

In five studies on ureteroscopic monotherapy, stone-free rate (SFR) ranged from 33% to 93%, with a maximum four ureteroscopy sessions per patient and no major complications. Endoscopic combined intrarenal surgery (ECIRS) was compared with percutaneous nephrolithotomy (PNL) in two studies and reached significantly higher SFR (88%-91% vs. 59%-65%) and lower operative times (84-110 min vs. 105-129 min). The role of salvage ureteroscopy for residual stones after primary PNL has been highlighted by two studies with a final SFR of 83%-89%. One study reported on the feasibility of ureteroscopy for ureteral stones and same-session PNL for contralateral staghorn calculi, with a SFR of 92%.

Conclusion

Ureteroscopy plays a pivotal role in the setting of a combined approach to staghorn calculi. Ureteroscopy is also particularly suitable for clearance of residual stones. In specific cases, ureteroscopy may become the sole applicable therapeutic option to staghorn calculi. Technological advances and refinement of techniques suggest a major role of ureteroscopy for staghorn calculi treatment in close future.

Safety and efficacy of Chinese minimally invasive percutaneous nephrolithotomy in the management of renal stones ≤ 2 cm: a single-center experience

Background

The goal for using smaller caliber instruments in PNL was to reduce the access-related complications and to decrease morbidity. The objective of this study was to evaluate the safety and efficacy of Chinese minimally invasive percutaneous nephrolithotomy (MIPNL) in the treatment of renal stones ≤ 20 mm.

Results

Sixty-seven patients completed the study protocol. The mean age was 41.10 ± 13.99 years (range 18–68 years). There were 43 (64%) male and 24 (36%) females. The mean stone size was ranged from 78.5 to 439.6 mm2 (mean ± SD 172.48 ± 69.54 mm2). The overall SFR was (82%). Twelve (18%) needed post-MIPNL auxiliary procedure, in the form of second MIPNL in 3 (4.5%) cases, SWL in 7 (10%), and RIRS in 2 (3%) cases. The intraoperative complication was present in four patients (5%) include bleeding necessitate blood transfusion in one patient (1.5%) and renal collecting system perforation 3 (4.5%). The postoperative complication was urine leakage 5 (7.5) and fever in 6 (9%) of patients.

Conclusion

Chinese MIPNL is safe and effective method for treatment of renal stone ≤ 20 mm size with satisfactory SFR and low complication rate when SWL failed or contraindicated. It is considered a feasible treatment alternative to standard PNL, in the absence of flexible URS or miniature nephroscope.

Endourologic Management (PCNL, URS, SWL) of Stones in Solitary Kidney: A Systematic Review from European Association of Urologists Young Academic Urologists and Uro-Technology Groups

Introduction: Urolithiasis in solitary kidney (SK) presents significant management dilemma as any insult to the kidney or its drainage can lead to significant morbidity. The treatment options include shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PCNL), and ureteroscopy (URS). Our aim was to conduct a systematic review of literature on all available endourologic techniques reporting on the management of stones in an SK. Materials and Methods: We conducted a systematic review according to the Cochrane and PRISMA checklist for all English-language articles from inception to December 2018. All studies with a minimum of 10 patients that reported on endourologic management (SWL, PCNL, or URS) were included. Data were extracted for patient and stone demographics, outcomes including stone-free rate (SFR), adverse events, and renal function. Results: After an initial search of 553 articles, 27 were included for the final review (10 PCNL, 1 mini-PCNL, 9 URS, 1 SWL, and 6 comparative studies). The choice of treatment seemed to be based on stone size, with PCNL, URS, and SWL offered for mean stone sizes between 25-50, 10-28, and 12-15 mm, respectively. PCNL, URS, and SWL were reported in 1445, 792, and 186 patients, respectively, with a final SFR of 67%-97.7%, 43%-100%, and 73%-80% and a complication rate of 26.4%, 15%, and 16.7% across the three groups. The renal function deterioration was reported in 4/16 PCNL studies and in 1/15 URS studies, while it remained unaffected in the SWL study. Conclusions: Our review shows a rise of endourologic techniques in the management of stones in SK. Although PCNL was used for larger stones, it had a higher risk of major complications, including blood transfusion. While a good SFR was obtained for patients irrespective of the treatment modality, the selected intervention needs to be balanced with its safety profile and the need for ancillary procedures.

Research progress of percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is generally accepted as the gold standard treatment for the treatment of large kidney stones (> 2 cm). For nearly 40 years, with the continuous progress of technology and the constant updating of ideas, PCNL has made great progress. In this review, we discuss the current research progress, recent advancement and hot spot of the whole process of PCNL including anesthesia, position, puncture, dilation, lithotripsy approaches, perfusate, tube placement, hospitalization time, drug, treatment of residual stones, prognosis judgment and operation evaluation by summarizing the related research in this article.

Tract Sizes in Miniaturized Percutaneous Nephrolithotomy: A Systematic Review from the European Association of Urology Urolithiasis Guidelines Panel

CONTEXT

Miniaturized instruments for percutaneous nephrolithotomy (PNL), utilizing tracts sized ≤22 Fr, have been developed in an effort to reduce the morbidity and increase the efficiency of stone removal compared with standard PNL (>22 Fr).

OBJECTIVE

We systematically reviewed all available evidence on the efficacy and safety of miniaturized PNL for removing renal calculi.

EVIDENCE ACQUISITION

The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Since it was not possible to perform a meta-analysis, the data were summarized in a narrative synthesis.

EVIDENCE SYNTHESIS

After screening 2945 abstracts, 18 studies were included (two randomized controlled trials [RCTs], six nonrandomized comparative studies, and 10 case series). Thirteen studies were full-text articles and five were only available as congress abstracts. The size of tracts used in miniaturized procedures ranged from 22 Fr to 4.8 Fr. The largest mean stone size treated using small instruments was 980mm². Stone-free rates were comparable in miniaturized and standard PNL procedures. Procedures performed with small instruments tended to be associated with significantly lower blood loss, while the procedure duration tended to be significantly longer. Other complications were not notably different between PNL types. Study designs and populations were heterogeneous. Study limitations included selection and outcome reporting bias, as well as a lack of information on relevant confounding factors.

CONCLUSIONS

The studies suggest that miniaturized PNL is at least as efficacious and safe as standard PNL for the removal of renal calculi. However, the quality of the evidence was poor, drawn mainly from small studies, the majority of which were single-arm case series, and only two of which were RCTs. Furthermore, the tract sizes used and types of stones treated were heterogeneous. Hence, the risks of bias and confounding were high, highlighting the need for more reliable data from RCTs.

PATIENT SUMMARY

Removing kidney stones via percutaneous nephrolithotomy (PNL) using smaller sized instruments (mini-PNL) appears to be as effective and safe as using larger (traditional) instruments, but more clinical research is needed.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for the treatment of kidney stones up to 2 cm in patients with solitary kidney: a single centre experience

BACKGROUND

To compare the treatment outcomes between percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for the management of stones larger than 2 cm in patients with solitary kidney.

METHODS

One hundred sixteen patients with a solitary kidney who underwent RIRS (n = 56) or PCNL (n = 60) for large renal stones (>2 cm) between Jan 2010 and Nov 2015 have been considered. The patients' characteristics, stone characteristics, operative time, incidence of complications, hospital stay, and stone-free rates (SFR) have been evaluated.

RESULTS

SFRs after one session were 19.6% and 35.7% for RIRS and PCNL respectively (p = 0.047), but the SFR at 3 months follow-up comparable in both groups (82.1% vs. 88.3%, p = 0.346). The calculated mean operative time for RIRS was longer (p < 0.001), but the mean postoperatively hospital stay was statistically significantly shorter (p < 0.001) and average drop in hemoglobin level was less (p = 0.040). PCNL showed a higher complication rate, although this difference was not statistically significant.

CONCLUSIONS

Satisfactory stone clearance can be achieved with multi-session RIRS in the treatment of renal stones larger than 2 cm in patients with solitary kidney. RIRS can be considered as an alternative to PCNL in selected cases.

Minimally invasive surgical treatment for kidney stone disease

Minimally invasive interventions for stone disease in the United States are mainly founded on 3 surgical procedures: extracorporeal shock wave lithotripsy, ureteroscopic lithotripsy, and percutaneous nephrolithotomy. With the advancement of technology, treatment has shifted toward less invasive strategies and away from open or laparoscopic surgery. The treatment chosen for a patient with stones is based on the stone and patient characteristics. Each of the minimally invasive techniques uses an imaging source, either fluoroscopy or ultrasound, to localize the stone and an energy source to fragment the stone. Extracorporeal shock wave lithotripsy uses a shock wave energy source generated outside the body to fragment the stone. In contrast, with ureteroscopy, laser energy is placed directly on the stone using a ureteroscope that visualizes the stone. Percutaneous nephrolithotomy requires dilation of a tract through the back into the renal pelvis so that instruments can be inserted directly onto the stone to fragment or pulverize it. The success of the surgical intervention relies on performing the least invasive technique with the highest success of stone removal.