Standard versus mini-percutaneous nephrolithotomy for renal stones: a meta-analysis

Abstract

Objective: To compare the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy in order to determine the optimal tract size for patients with renal stones. Methods: A systematic search of Web of Science, EMBASE, Cochrane Library, and PubMed databases was conducted for articles published through 20 August 2019, reporting on a comparison of the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: Of 763 studies, 14 were considered for the evidence synthesis. A total of 1980 cases were included. Of these patients, 897 cases underwent standard percutaneous nephrolithotomy, and 1083 cases underwent mini-percutaneous nephrolithotomy. Stone-free rates were 87.6% (786 of 897 patients) for standard percutaneous nephrolithotomy and 87.8% (951 of 1083 patients) for mini-percutaneous nephrolithotomy ( p = 0.57). Tract sizes of 30F and 22–26F in standard percutaneous nephrolithotomy group shorten operation time compared with mini-percutaneous nephrolithotomy ( p = 0.02; p = 0.004; respectively). Leakage ( p = 0.04), bleeding ( p = 0.01), blood transfusion ( p < 0.00001), and renal pelvis perforation ( p = 0.02) were more common in standard percutaneous nephrolithotomy group than in mini-percutaneous nephrolithotomy group. Subgroup analysis showed only blood transfusion for 30F and 22–26F standard percutaneous nephrolithotomy group was more common than mini-percutaneous nephrolithotomy ( p < 0.0001, p = 0.005, respectively). Conclusion: Standard percutaneous nephrolithotomy was associated with higher leakage, bleeding, blood transfusion, and renal pelvis perforation, but had a shorter operation time. Tract size of 30F improved the stone-free rate compared with mini-percutaneous nephrolithotomy, but led to more complications. Tract size of 22–26F was no better than 30F or mini-percutaneous nephrolithotomy.

Mini-percutaneous nephrolithotomy in surgery of nephrolithiasis

“…This may facilitate improvements in stone-free rates as smaller fragments are formed which can irrigate out through the tract. Similar to our study, improved effectiveness of mPNL was seen in a study by Zhong W., et al [21] where the mPNL was associated with significantly better SFR (89.7 vs 68.0%, p=0.049) compared to sPNL and lower need for a secondary procedure(13.8 vs 28.0%, p=0.048); and in the meta-analysis by Deng J, et al [22], where the stone-free rate was 87.6% with sPNL and 87.8% with mPNL (p=0.57). In our experience, higher SFR of mPNL among all types of renal calculi were, compared with sPNL (96.4 versus 91.8%, p=0.002).…”

“…Despite the higher safety profile mPNL a number of authors have reported differences in stone-free rate (SFR) in favor of sPNL. These differences are most notable when comparing the results of treatment of staghorn and multiple renal calculi [11][12][13].…”

“…To date, the main surgical methods for treatment of renal stones with sizes up to 1.5-2.0 cm are shock wave lithotripsy and retrograde intrarenal surgery (RIRS), with PNL reserved for larger calculi or branched staghorn calculi or in cases where anatomic abnormalities preclude successful treatment with SWL or RIRS. The most important advantage of RIRS over PNL is its lower invasiveness and, accordingly, lower complication rate [13,14]. However, the higher cost of operating the equipment, need for frequent multiple procedures and lower stone-free rates are an important drawback which maintains a role for various PNL techniques [15,16].…”

Miniaturized percutaneous nephrolithotomy

“…Despite the availability of multiple RCTs and meta-analyses, the current major guidelines do not recommend mPNL due to a lack of high-quality evidence. [ 2 3 ] This study by Zeng et al . is the first well-conducted multi-center, open-labeled RCT comparing sPNL with mPNL.…”

“…Similar to this study, Deng et al . [ 3 ] and Jiao et al . [ 2 ] noted a similar SFR in the two groups in their meta-analyses.…”