Ultramini-percutaneous nephrolithotomy versus retrograde intrarenal surgery in the treatment of 10-30 mm calculi: a randomized controlled trial

Endourological Management of Renal Stones: A Systematic Review, Bayesian Network Meta-analysis and Meta-regression

OBJECTIVE

To compare stone-free rates (SFRs), operative times, and transfusion rates of various endoscopic techniques for kidney stone management.

METHODS

A systematic review was performed, identifying studies comparing the different endoscopic techniques in patients with renal stones. Studies were grouped by location and size of stones (lower pole, 1-2cm, and >2 cm). Data were extracted to build a Bayesian network modeling the comparisons. Meta-regression adjusted for variations in stone-free definitions. Odds ratios (OR) with 95% credible intervals were reported.

RESULTS

A total of 40 studies were included for analysis, providing a total population of 6696 patients. For lower pole stones, both percutaneous nephrolithotomy (PCNL) (OR 2.0 [1.2, 3.3]) and mini-PCNL (OR 2.3 [1.5, 3.6]) showed increased SFRs when compared to retrograde intrarenal surgery (RIRS), while micro-PCNL exhibited a non-significant difference (OR 0.94 [0.39,2.3]). For stones between 1-2cm, mini-PCNL showed an increased SFR (OR 2.5 [1.5,4.1]) when compared to RIRS; however, there was no significant difference in SFR among the rest of the interventions when compared to RIRS. For stones larger than 2 cm, PCNL, mini-PCNL, and ultramini-PCNL resulted in higher SFRs compared to RIRS.

CONCLUSION

For 1-2cm upper pole/interpolar stones, percutaneous approaches except mini-PCNL did not achieve superior SFRs compared to RIRS. For >2 cm stones and lower pole stones, all percutaneous methods, except micro-PCNL, exhibited higher stone clearance than RIRS.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for treatment of renal stones in adults

BACKGROUND

Kidney stones (also called renal stones) can be a source of pain, obstruction, and infection. Depending on size, location, composition, and other patient factors, the treatment of kidney stones can involve observation, shock wave lithotripsy, retrograde intrarenal surgery (RIRS; i.e. ureteroscopic approaches), percutaneous nephrolithotomy (PCNL), or a combination of these approaches.

OBJECTIVES

To assess the effects of percutaneous nephrolithotomy (PCNL) versus retrograde intrarenal surgery (RIRS) for the treatment of renal stones in adults.

SEARCH METHODS

We performed a comprehensive search of the Cochrane Library, MEDLINE, Embase, Scopus, and two trials registries up to 23 March 2023. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized controlled trials that evaluated PCNL (grouped by access size in French gauge [Fr] into three groups: ≥ 24 Fr [standard PCNL], 15-23 Fr [mini-PCNL and minimally invasive PCNL], and < 15 Fr [ultra-mini-, mini-micro-, super-mini-, and micro-PCNL]) versus RIRS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data from the included studies. Our primary outcomes were stone-free rate, major complications, and need for secondary interventions. Our main secondary outcomes were unplanned medical visits to emergency/urgent care or outpatient clinic, length of hospital stay, ureteral stricture or injury, and quality of life. We performed statistical analyses using a random-effects model. We rated the certainty of evidence using GRADE criteria. We adopted a minimally contextualized approach with predefined thresholds for minimal clinically important differences (MCIDs).

MAIN RESULTS

We included 42 trials assessing the effects of PCNL versus RIRS in 4571 randomized participants. Twenty-two studies were published as full-text articles, and 20 were published as abstract proceedings. The average size of stones ranged from 10.1 mm to 39.1 mm. Most studies did not report sources of funding or conflicts of interest. The main results for the most important outcomes are summarized below. Stone-free rate PCNL compared with RIRS may improve stone-free rates (risk ratio [RR] 1.13, 95% confidence interval [CI] 1.08 to 1.18; I2 = 71%; 39 studies, 4088 participants; low-certainty evidence). Based on 770 participants per 1000 being stone-free with RIRS, this corresponds to 100 more (62 more to 139 more) stone-free participants per 1000 with PCNL (an absolute difference of 10%, where the predefined MCID was 5%). Major complications PCNL compared with RIRS probably has little or no effect on major complications (RR 0.86, 95% CI 0.59 to 1.25; I2 = 15%; 34 studies, 3649 participants; moderate-certainty evidence). Based on 31 complications in the RIRS group, this corresponds to six fewer (13 fewer to six more) major complications per 1000 with PCNL (an absolute difference of 0.6%, where the predefined MCID was 2%). Need for secondary interventions PCNL compared with RIRS may reduce the need for secondary interventions (RR 0.31, 95% CI 0.17 to 0.55; I2 = 61%; 21 studies, 2005 participants; low-certainty evidence). Based on 222 secondary interventions in the RIRS group, this corresponds to 153 fewer (185 fewer to 100 fewer) secondary interventions per 1000 with PCNL (an absolute difference of 15.3%, where the predefined MCID was 5%). Unplanned medical visits No studies reported unplanned medical visits. Length of hospital stay PCNL compared with RIRS may extend length of hospital stay (mean difference 1.04 days more, 95% CI 0.27 more to 1.81 more; I2 = 100%; 26 studies, 2804 participants; low-certainty evidence). This effect size is greater than the predefined MCID of one day. Ureteral stricture or injury PCNL compared with RIRS may have little or no effect on the occurrence of ureteral strictures (RR 0.93, 95% CI 0.39 to 2.21; I2 = 0%; 13 studies, 1574 participants; low-certainty evidence). Based on 14 ureteral strictures in the RIRS group, this corresponds to one fewer (nine fewer to 17 more) ureteral strictures per 1000 with PCNL (an absolute difference of 0.1%, where the predefined MCID was 2%). Quality of life No studies reported quality of life.

AUTHORS' CONCLUSIONS

Based on a large body of evidence from 42 trials, we found that PCNL compared with RIRS may improve stone-free rates and may reduce the need for secondary interventions, but probably has little or no effect on major complications. PCNL compared with RIRS may have little or no effect on ureteral stricture rates and may increase length of hospital stay. We found no evidence on unplanned medical visits or participant quality of life. Because of the considerable shortcomings of the included trials, the evidence for most outcomes was of low certainty. Access size for PCNL was less than 24 Fr in most studies that provided this information. We expect the findings of this review to be helpful for shared decision-making about management choices for individuals with renal stones.

Efficacy and safety of minimally invasive percutaneous nephrolithotomy versus retrograde intrarenal surgery in the treatment of upper urinary tract stones (> 1 cm): a systematic review and meta-analysis of 18 randomized controlled trials

BACKGROUND

The advantages and disadvantages of retrograde intrarenal surgery (RIRS) and minimally invasive percutaneous nephrolithotomy (mPCNL) for treatment of upper urinary tract calculi have not been conclusively determined.

METHODS

In this meta-analysis, We comprehensively evaluated the performance of the two surgical approaches in treatment of upper urinary calculi. We searched the Pubmed, Embase, Cochrane and Web of science databases for randomized controlled trial (RCT) articles on RIRS and mPCNL upto December 2022. Data were extracted by two independent reviewers and subjected to the meta-analysis using the Stata 15.1 software (StataSE, USA).

RESULTS

A total of 18 eligible RCTs involving 1733 patients were included in this study. The meta-analysis revealed that mPCNL of 1-2 cm or 2-3 cm stones had a higher stone clearance rate (RR:1.08, 95%CI (1.03, 1.14), p = 0.002) and shorter operation time (WMD : -10.85 min, 95%CI (-16.76, -4.94), p<0.001). However, it was associated with more hospital stay time (WMD :1.01 day, 95%CI(0.53, 1.5), p<0.001), hemoglobin drops (WMD :0.27 g/dl, 95%CI (0.14, 0.41), p<0.001), blood transfusion rate (RR:5.04, 95%CI(1.62, 15.65), p = 0.005), pain visual analogue score (WMD:0.75, 95%CI (0.04, 1.46), p = 0.037), hospital costs (SMD :-0.97, 95%CI (-1.19, -0.76), p<0.001) and major complications (RR:1.89, 95%CI(1.01, 3.53), p = 0.045).

CONCLUSION

Therefore, in terms of surgical effects and operation time, mPCNL is superior to RIRS, but is inferior with regards to other perioperative parameters. These factors should be fully considered in clinical decision making.

Comparison of flexible ureteroscopy and mini-percutaneous nephrolithotomy in the treatment for renal calculi larger than 2 cm: a matched-pair analysis

To compare the effectiveness and safety of flexible ureteroscopy and mini-percutaneous nephrolithotomy for renal calculi > 2 cm and perform subgroup analysis of stone length and age. Patients received mini-percutaneous nephrolithotomy or flexible ureteroscopy in Qilu Hospital of Shandong University from 2016.01 to 2021.03 with renal calculi > 2 cm were retrospectively analyzed. Propensity score matching was performed to get comparable patients. The postoperative hospital days, operation time, complication rate, and stone free rate were compared. The age and stone length were analyzed by subgroup. 162 in 313 patients were finally included. Each group had 81 cases. Outcomes such as intraoperative transfusion, stone free rate show no difference either. Flexible ureteroscopy had shorter postoperative hospital days (3.2 days vs 7.2 days, P < 0.001) and fewer complications (9, 11.1% vs 25, 30.9%, P = 0.002) compared to mini-percutaneous nephrolithotomy. The postoperative hospital days, and complication of the flexible ureteroscopy were significantly lower than those in the mini-percutaneous nephrolithotomy for renal stones ≤ 2.5 cm; when the stone length > 2.5 cm, the stone free rate of flexible ureteroscopy was lower than that of the mini-percutaneous nephrolithotomy group, but not statistically significant. The complications of flexible ureteroscopy in the young group (18-39 years old) were significantly lower than those in the mini-percutaneous nephrolithotomy group. For 2-2.5 cm renal stones, flexible ureteroscopy can achieve a similar stone free rate with shorter hospital stay, and lower complications. For larger stones, flexible ureteroscopy performed poorly. Flexible ureteroscopy may be a better option for younger patients with fewer complications.