Micropercutaneous Nephrolithotomy Research Articles

The predictive ability of Mayo adhesive probability score for evaluating intraoperative bleeding in standard percutaneous nephrolithotomy in adult patients.

Mayo adhesive probability (MAP) score is one of the commonest tool to predict the adherence status of perirenal fat. The association between MAP score and intraoperative hemorrhage in patients undergoing micropercutaneous nephrolithotomy was comfirmed in a recent well designed study. We aimed to investigate if MAP score may predict the possibility for significant intraoperative bleeding in supine percutaneous nephrolithotomy (PCNL) performed with a 26 Fr rigid nephroscope. In this observational retrospective study, demographic, clinical, laboratory, radiological, perioperative (operation duration, hospitalization, intraoperative bleeding, success) and MAP score (perinephric fat stranding, posterior perinephric fat thickness and total MAP score) data of all patients who underwent supine PCNL between June 2021 and July 2023 were evaluated. The patients were divided into 2 groups according to their MAP scores (79 [54.1%] patients with MAP score < 3 [low MAP score] and 67 [54.1%] patients with MAP score ≥ 3 [high MAP score]). The rate of patients with intraoperative bleeding was 47.8% in the patient group with a high MAP score, while it was 22.8% in the patient group with a low MAP score (p = 0.002). In multivariate logistic regression analysis, anticoagulant drug use history (OR = 2.525; 95% CI = 1.025-6.224; p = 0.044), presence of multiple stones (OR = 3.015; 95% CI = 1.205-7.543; p = 0.018), calyx localization of the stone (OR = 2.871;95% CI = 1.166-7.068; p = 0.022), higher renal parenchymal thickness (OR = 1.119; 95% CI = 1.049-1.193; p = 0.001) and MAP score > 3 (OR = 3.486; 95% CI = 1.579-7.696; p = 0.002) were defined as independent risk factors for significant intraoperative bleeding. In clinical practice, the MAP score can be used to predict bleeding before PCNL.

Comparison of percutaneous nephrolithotomy and flexible ureterorenoscopy in the treatment of single upper ureteral calculi measuring 1 to 2 centimeters: a retrospective study

PurposeTo compare the efficacy and safety of micropercutaneous nephrolithotomy (MPCNL) and flexible ureteroscopy (FURS) in the treatment of single upper ureteral calculi measuring 1 to 2 centimeters.MethodsThis study is a retrospective analysis that combines a review of medical records with an outcomes management database. A total of 163 patients who underwent MPCNL and 137 patients who had FURS were identified between January 2017 and December 2021. Demographic data, operation time, hospitalization time, stone-free rate, and complication rate were collected and analyzed.ResultsPreoperative general data of sex, age, BMI, serum creatinine, time of stone existence, stone hardness, stone diameter, preoperative hydronephrosis, and preoperative infection of the MPCNL group have no statistically significant difference with that of the FURS group. All MPCNL or FURS operations in both groups were successfully completed without any instances of reoperation or conversion to another surgical procedure. Patients who underwent MPCNL had a considerably reduced operation time (49.6 vs. 72.4 min; P<0.001), but a higher duration of hospitalization (9.1 vs. 3.9 days; P<0.001) compared to those who underwent FURS. The stone-free rate in the MPCNL group was superior to that of the FURS group, with a percentage of 90.8% compared to 71.5% (P<0.001). There was no statistically significant disparity in the rate of complications between the two groups (13.5% vs. 15.3%; P = 0.741).ConclusionBoth MPCNL and FURS are viable and secure surgical choices for individuals with solitary upper ureteral calculi measuring 1 to 2 cm. The FURS procedure resulted in a shorter duration of hospitalization compared to MPCNL. However, it had a comparatively lower rate of successfully removing the stones and required a longer duration for the operation.There were no substantial disparities observed in the complication rate between the two groups.FURS is the preferable option for treating uncomplicated upper ureteral calculi, whereas MPCNL is the preferable option for treating complicated upper ureteral calculi.Prior to making treatment options, it is crucial to take into account the expertise of surgeons, the quality of the equipment, and the preferences of the patient.Trial registrationNo.

Endoscopic combined intrarenal surgery composed of micro-perc and retrograde intrarenal surgery in the treatment of complex kidney stones in children.

This research aims to explore the efficiency and safety of endoscopic combined intrarenal surgery (Micro-ECIRS) composed of micro-percutaneous nephrolithotomy (Micro-perc) and retrograde intrarenal surgery (RIRS) in the Galdakao-modified supine Valdivia (GMSV) position for a single session for the treatment of complex nephrolithiasis in children. This study retrospectively reviewed patients aged < 18years who underwent Micro-ECIRS in the GMSV position for renal stones larger than 2cm under ultrasound guidance between August 2020 to May 2022 at our institution. A total of 13 patients (8 males and 5 females) received Micro-ECIRS for renal stones under ultrasound guidancewhile adopting the GMSV position. The average stone size was 2.7cm (range: 2.1-3.7cm). Among them, 6 patients had left kidney stones, 5 patients had right kidney stones, and 2 patients had bilateral kidney stones. The mean operative time was 70.5min (range: 54-93min). The mean hospital stay was 6.4days (range: 4-9days). The mean hemoglobin decrease was 8.2g/L (range: 5.1-12.4g/L). The total number of kidneys that had complete stone clearance was 8 kidneys at 48h postoperatively, 11 kidneys at 2weeks postoperatively, and 14 kidneys at 1month postoperatively. Our results demonstrate that Micro-ECIRS while patients are in the GMSV position is a safe and effective method for the treatment of complex children nephrolithiasis. However, all children made three hospital visits and received anesthesia three times. Further research is needed to confirm these findings.

Application of Micro-Percutaneous Nephrolithotomy (Micro-PCNL) combined with FURL in 1-2 cm symptomatic, refractory lower calyceal stones.

To investigate the safety and efficacy of Micro-Percutaneous Nephrolithotomy (Micro-PCNL) combined with flexible ureteroscopic lithotomy (FURL) in the treatment of 1-2 cm symptomatic, refractory lower calyceal stones. A retrospective analysis was performed concerning the clinical data of 28 patients with 1-2 cm symptomatic, refractory lower calyceal stones. When there was a difficulty in performing FURL in Affiliated Hospital of Hebei University from January 2019 to February 2022, ultrasound-guided F4.8 visual puncture was performed on the lower calyceal stone,with a holmium laser was then used to treat the remaining stones, followed by drainage using a flexible ureteroscopic sheath and postoperative indwelling of the ureteral stent without a nephrostomy tube. The surgery time, intraoperative bleeding and stone-free rate(SFR) were recorded, and the VAS score was used to evaluate the patients' pain status. The surgery was completed successfully in an average of 43.46 ± 10.04 minutes, and the puncture time was 3.46 ± 0.69 minutes. The SFR was 85.71%(24/28) and 92.86%(26/28) at one day and 30 days after surgery, respectively. Two patients with residual stones greater than 0.6 cm in size underwent extracorporeal shock wave lithotripsy four weeks after surgery. Patients were followed up for three months after surgery, and the SFR was revised to 96.43%(27/28). In addition, the VAS scores of all patients decreased significantly from before to after surgery, and the difference was statistically significant(p< 0.05). Micro-Percutaneous Nephrolithotomy (Micro-PCNL) combined with FURL is safe and effective in the treatment of 1-2 cm symptomatic, refractory lower calyceal stones.

Single-center experience of micro-perc in the treatment of children with 1.0-2.0cm sized kidney stones in the Galdakao-modified supine Valdivia position.

We aimed to explore the applicability and safety of micro-percutaneous nephrolithotomy (micro-perc) in the treatment of children with kidney stones in the Galdakao-modified supine Valdivia (GMSV) position under the guidance of whole-course ultrasound. Patients were aged < 18years in the GMSV position who underwent micro-perc for kidney stones under ultrasound guidance between August 2020 and May 2022 at our institution were reviewed retrospectively. A total of 23 patients, 15 males and 8 females, received micro-perc. The average stone size was 1.6cm (range 1.1-2.0cm). Among them, 12 patients had left kidney stones, 10 patients had right kidney stones, and 1 patient had bilateral kidney stones. The mean operative time was 55.3min (range 35-86min). The mean hospital stay was 2.9days (range 2-4days). The mean hemoglobin decrease was 1.7g/L (range 0.9-3.2g/L). A total of 17 patients had complete stone clearance at 48h postoperatively. A total of 22 patients had complete stone clearance at 2weeks postoperatively. Our results demonstrate that micro-perc under ultrasound guidance is a safe and effective method for the treatment of children with kidney stones in the GMSV position. Further research is warranted to confirm these results.

A multi-institutional experience of Micro-percutaneous Nephrolithotomy (MicroPERC) for renal stones: Results and feasibility of day case surgery.

To report the multi-institutional outcomes of Microperc for nephrolithiasis and to assess its feasibility in outpatient care. We retrospectively identified all adult patients who underwent Microperc for renal stones at three centres between May 2015 and March 2021. Interventions were performed by three Surgeons. One Surgeon adopted a "one-way" strategy and all Microperc were performed on an outpatient basis, while the other two Surgeons provided inpatient monitoring for at least one day after surgery. The primary endpoint was same-day discharge after Microperc without emergency department visits or unplanned readmission within 30 days of the procedure. The secondary endpoints included treatment outcomes and the 30-day complication rate. Out of 72 consecutive patients included, 32 patients (44.4%) had same-day discharge. Median Charlson score (1 [0-2]) and cumulative stone size (15 [12-20] mm) were comparable between both groups. At one month post procedure, 32 patients (44.4%) were stone free and 23 patients (32%) had residual micro-fragments<3mm, conferring an overall success rate of 76.4% (inpatient Microperc group: 77.5% vs outpatient Microperc group: 75%, P=1). Analysis of the 30-day complication rate showed similar results between the two groups (Clavien I-II: 18.1%, Clavien≥III: 4.1%). After outpatient care, the rate of immediate admission and unplanned readmission was 12.5% (n=4), mainly due to urinary tract infection. In this multi-institutional study, we report that outpatient Microperc is feasible in selected patients with no significant impact on postoperative outcome.

Editorial comment on comparison of the micro-percutaneous nephrolithotomy results between adult and pediatric cases: Is it safe and effective for pediatric cases? Seçkiner et al.

Editorial comment on comparison of the micro-percutaneous nephrolithotomy results between adult and pediatric cases: Is it safe and effective for pediatric cases? Seçkiner et al.

Microperc with Self-Assembled Fr 4.85 Visual Needle and Ureteral Access Sheath

Background Micropercutaneous nephrolithotomy (microperc) is the least invasive among percutaneous nephrolithotripsy (PCNL) procedures. Although microperc has a high stone-free rate and certain advantages over other methods, modifications may be needed to improve the technique. We describe our experience performing microperc using a self-assembled visual needle and ureteral access sheath (UAS). Methods Between June 2016 and April 2019, the data of 30 patients with kidney stones undergoing microperc with our self-assembled 4.8 Fr visual needle combined with a UAS was retrospectively analyzed. Patients were placed in an obilique spine lithotomy position. Results Two cases were excluded: one due to conversion to mini PCNL and the other required flexible ureteroscopy during microperc. The remaining 28 cases included 18 men and 10 women, age 38.4 ± 7.5 years, stone size 1.7 ± 0.4 cm, and stone density on CT 969 ± 233 HU. Operative time was 47 ± 9.9 minutes, visual analogue scale score of tract pain on postoperative day 1 was 2.5 ± 1.0, hemoglobin decrease was 6.4 ± 1.0 g/L, and hospital stay was 3.1 ± 0.8 days. There was 1 case of fever and urinary infection, 2 cases of hematuria, and 1 case of flank pain. All symptoms resolved after conservative or antibiotic treatment. On postoperative day 1, 12 (42.9%) caseswere stone-free. The stone-free rates at postoperative month 1 and 3 were 92.9% (26/28) and 100% (28/28), respectively. Conclusions Our self-assembled visual needle and UAS instrument is effective for microperc. Use of the UAS may improve the operative outcome.

Comparison of Efficiency and Safety of Retrograde Intrarenal Surgery and Micropercutaneous Nephrolithotomy in Pediatric Kidney Stones Smaller than 2 cm: A Prospective Cohort Study.

Objective: To compare the safety and efficacy of two minimally invasive surgical techniques used for pediatric stone disease: retrograde intrarenal surgery (RIRS) and micropercutaneous nephrolithotomy (micro-PCNL). Materials and Methods: A prospective study was designed to include children aged <15 years with a single stone <20 mm. Sixty-four patients were assigned to undergo either an RIRS or a micro-PCNL (1:1 ratio). Demographic parameters, stone size, location, operative data, complications, stone-free status, and efficacy quotient were compared. Results: Due to anatomic considerations, seven patients were shifted to the micro-PCNL arm, thus resulting in 39 micro-PCNLs performed vs 25 RIRS in the end. Because of the deviation from planned surgery that was significantly higher in the RIRS group (p = 0.011), the analysis was done in a prospective cohort comparison. Stone-free rates were similar for micro-PCNL and RIRS groups (80% vs 82.2%). The operative (median 60 vs 90 minutes, p < 0.001), fluoroscopy (median 15 vs 30 seconds, p = 0.004), and lithotripsy times (median 15 vs 25 minutes, p = 0.007) were shorter in the RIRS group. However, despite the larger stone size, the efficiency quotient was significantly higher in the micro-PCNL group (82.1% vs 54.1%; p = 0.009). None of the patients experienced significant hematuria requiring blood transfusion, as well as no ureteral orifice obstructive complication was detected within the follow-up period. Conclusion: RIRS and micro-PCNL techniques in children have similar stone-free and complication rates. The operative, fluoroscopy, and lithotripsy times were shorter, deviation from the planned surgery, and the number of sessions under anesthesia was higher in the RIRS group. Despite the larger stone size, efficacy quotient was significantly higher in the micro-PCNL group.

Nomograms predicting the outcomes of endoscopic treatments for pediatric upper urinary tract calculi.

To demonstrate the efficacy and safety of mini-percutaneous nephrolithotomy, micro-percutaneous nephrolithotomy, and flexible ureteroscopy for pediatric upper urinary tract calculi and to develop nomograms predicting surgical outcomes. A prospectively managed database containing children who were diagnosed with upper urinary tract calculi and treated with mini-percutaneous nephrolithotomy, micro-percutaneous nephrolithotomy, and flexible ureteroscopy between June 2014 and April 2019 was analysed. Patient demographics, intraoperative data, stone characteristics, stone-free rate, and complication rate were analysed and compared. Nomograms predicting the postoperative stone-free rate and complication rate were established based on predictors, and internal validation was performed. Calibration curves and decision curves were generated to assess the predictive efficacy and clinical benefit. Forty-three children underwent mini-percutaneous nephrolithotomy on 56 sides in 47 operations, 30 children underwent micro-percutaneous nephrolithotomy on 30 sides in 30 operations, and 275 children underwent flexible ureteroscopy on 320 sides in 288 operations. The stone-free rates were 88.5% (282/320) for flexible ureteroscopy, 89.3% (50/56) for mini-percutaneous nephrolithotomy, and 90.0% (27/30) for micro-percutaneous nephrolithotomy (P=0.94). And the complication rates were 19.8% (57/288), 36.2% (17/47), and 33.3% (10/30), respectively (P=0.02). Nomograms based on stone characteristics, operation duration, and the physical condition of the child were shown to have good discrimination and calibration. The area under the curve of the models was 81% for stone-free rate and 73% for complication rate. The calibration curves showed that the nomogram might underestimate the probability of stone-free rate when the threshold was below 82% and might overestimate the risk of complication rate when the threshold was over 25%. The decision curves demonstrated that the Capital Medical University nomograms improved clinical risk prediction against threshold probabilities of stone-free rate ≤20% and complication rate ≤10%. Both the percutaneous nephrolithotomy and flexible ureteroscopy procedures could have acceptable stone-free rates when treating pediatric stones. The Capital Medical University nomograms performed well in helping to predict stone-free and complication rates.

Comparative Evaluation of Micropercutaneous Nephrolithotomy and Retrograde Intrarenal Surgery in the Management of Renal Stones 10–20 mm in Size

Comparative Evaluation of Micropercutaneous Nephrolithotomy and Retrograde Intrarenal Surgery in the Management of Renal Stones 10–20 mm in Size

Comparison of Retrograde Intrarenal Surgery and Micro-Percutaneous Nephrolithotomy for Kidney Stones: A Meta-Analysis

Background: Advances in micro-percutaneous nephrolithotomy (PCNL) for kidney stones have made it an alternative approach to the retrograde intrarenal surgery (RIRS) approach. Nevertheless, the superiority of micro-PCNL over RIRS is still under debate. The results are controversial. Objectives: The purpose of this study was to systematically evaluate the clinical results in patients presenting with kidney stones treated with micro-PCNL or RIRS. Methods: A literature search was done for electronic databases to identify researches that compared micro-PCNL and RIRS till December 2019. The clinical outcome included complications, stone-free rates (SFRs), hemoglobin reduction, length of hospital stay, and operative time. Results: Five articles were included in our study. The pooled results revealed no statistical difference in the rate of complications (OR = 0.99, 95% CI = 0.57–1.74, p = 0.99), length of hospital stay (MD = −0.29, 95% CI = −0.82 to 0.24, p = 0.28), and operative time (MD = −6.63, 95% CI = −27.34 to 14.08, p = 0.53) between the 2 groups. However, significant difference was present in hemoglobin reduction (MD = −0.43, 95% CI = −0.55 to 0.30, p < 0.001) and the SFRs (OR = 0.59, 95% CI = 0.36–0.98, p = 0.04) when comparing RIRS with micro-PCNL. Conclusions: Compared with micro-PCNL to treat kidney stones, RIRS is associated with better stone clearance and bearing higher hemoglobin loss. As the advantages of both technologies have been shown in some fields, the continuation of well-designed clinical trials may be necessary.

Micropercutaneous Laser Lithotripsy: How to Improve Stone Free Rate

Introduction: Micropercutaneous Nephrolithotomy is a novel technique with the creation of a 4.85-8F working channel. The advantage of micro-PCNL is the possibility of kidney puncture under direct endoscopic control. Materials and Methods: 99 patients aged 47,3 ± 16.9 years were included in the study. 78 patients had isolated kidney stones (78.8%). The stone size ranged from 8 to 38 mm (13.9 ± 5.4 mm). Group A included stones smaller than 15 mm (57 patients, 57,6%) and Group B included stones larger than 15 mm (42 patients, 42,4%). A 4.85 F percutaneous sheath was used in 38 (38,4%) patients, 8 F sheath was used in 61 (61,6%) patients. A holmium laser for lithotripsy was used in 46.5% cases, the thulium fiber laser in 53.5%. Results: The average surgery time was 39,9 ± 13.7 min (from 13 to 75 min). A stone-free rate (SFR) for patients of both groups was 88.8%. A Double-J stent was placed in 39 (39.4%) patients. In one case conversion to the mini-PCNL was done. In four cases (4%) retrograde stone manipulations were performed through ureteral access sheath. 5 (5.1%) patients required the second micro-PCNL tract. 3 (3%) patients required stenting postoperatively. In 7.1% of cases the episode of acute pyelonephritis developed. In 7 cases (7,1%), Extracorporeal Shock Wave Lithotripsy was required due to residual stones. Conclusions: We recommend using the laser micro-PCNL for the category of patients with severe comorbidities, including coagulopathy. The micro-PCNL could be safely performed in patients with kidney stones larger than 1.5 cm.

Does Previous Open Stone Surgery Affect the Outcome of Shock Wave Lithotripsy Treatment in Children?

Introduction: The aim of the study was to evaluate the efficiency of shock wave lithotripsy (SWL) in children who previously underwent ipsilateral open renal stone surgery (ORSS). Methods: A total of 315 renal units (RUs) with renal stones underwent SWL treatment in our department over a period of 18 years. A total of 274 RUs (87%) with no history of ORSS were categorized as group 1 and 41 RUs (13%) with a history of ORSS were categorized as group 2. The characteristics of the patients and renal stones, as well as the treatment modalities, were reviewed retrospectively, and the results were compared in terms of the rates of stone-free patients and complications. Results: The stone-free rates were statistically lower in patients with an existing history of ORSS (p = 0.002), especially for stones located at the lower calyx (p = 0.006). However, there were no differences between groups in the rate of complications (p = 0.75). History of ipsilateral ORSS, age, and stone burden were independent risk factors that predicted a stone-free status in the regression analysis (p = 0.016, p = 0.045, and p = 0.001, respectively). Conclusion: The overall stone-free rate after SWL was found to be significantly lower in children with a history of ORSS than in those without, and this finding was significantly prominent for lower calyx stones. In spite of the possible difficulties in achieving surgical access due to anatomical changes in retrograde intrarenal surgery or mini-/micro-percutaneous nephrolithotomy, we believe that these techniques might be good alternatives for SWL in future cases.

Comperative Evaluation of Micropercutaneous Nephrolithotomy and Retrograde Intrarenal Surgery in the Management of Renal Stones Size of 10-20mm

Comperative Evaluation of Micropercutaneous Nephrolithotomy and Retrograde Intrarenal Surgery in the Management of Renal Stones Size of 10-20mm

746 - Ultrasound-guided micro-percutaneous nephrolithotomy in the treatment of pediatric nephrolithiasis

746 - Ultrasound-guided micro-percutaneous nephrolithotomy in the treatment of pediatric nephrolithiasis

Micro-percutaneous nephrolithotomy (Microperc) for renal stones, outcomes and learning curve

To report the effectiveness, reliability and learning curve of Microperc, a minimal invasive percutaneous technique using a 4.85-Ch (16-gauge) sheath, in the treatment of nephrolithiasis. 31 consecutive Micropercs for nephrolithiasis<2.5cm were performed by 2 operators in 2 different institutions from the 1st of May 2015 to 31st of December 2017. The mean size of stones was 19mm±11mm, and mean density was 1048±249UH. Stones were located in lower calyx in 21/31(68%), medium calyx in 3/31(10%), pelvis in 4/31(12%) and were multi-caliceal in 3/31(10%). Five patients (16%) had urinary diversion (4 ileal conduits, 1 enterocystoplasty with Mitrofanoff+bladder neck closure) all of those having neurological disease (2 multiple sclerosis, 3 spinal cord injury). Mean operating time was 83±35min and decreased after short period for both operators. 9/31(29%) patients had complication: 8 (26%) had fever (Clavien II) and 1 (3%) had renal colic pain (Clavien III) (required JJ stent). Stone-free was obtained in 13/31(42%) and 11/31(36%) had residual microfragments<3mm which did not require further treatment, corresponding to a technical success of 78% (24/31). Success rate was similar in patients with urinary diversion and patients with normal anatomy. This study showed that Microperc was an effective technic for kidney stone treatment with low complication rate, acceptable operating time and short learning curve. Microperc was useful for stones in the lower calyx and/or urinary diversion where retrograde ureteroscopy could reach its limits. 3.

The evaluations of ESWL, RIRS and m-PCNL treatments in kidney stones smaller than two centimeters

Objective: The aim of the current study was to compare the outcome of minimal invasive treatment (RIRS, m-PCNL) with the ESWL, Micro-Percutaneous Nephrolithotomy (m-PCNL), and Retrograde intrarenal surgery (RIRS) in patients with renal calculi less than two centimeters in size.&#x0D; Methods: Preoperative renal ureter-bladder (KUB) film and computed tomography (CT) used to imaging stone size and localization in all patients. Ninety consecutive patients were randomized equally to three groups. We evaluated age, gender, stone size, length of hospitalization, stone-free rates, X-ray duration that patients were exposed during the processes, general anesthesia time, Visual Analogue Scale values, Modified Clavien Complication Scale scores after RIRS, mPCNL, and ESWL on renal stones smaller than 2 cm.&#x0D; Results: At the end of the first month, stone-free rate for the lower calyx stones was 33.3% (3 patients out of 10) in ESWL, 83.3% (10 patients out of 12) in RIRS, and 90.9% (10 patients out of 11) in m-PCNL. ESWL's success in the lower-calyx stones was found to be low. Our rates for the stones in renal pelvis, middle, and upper calyx were % 85.7 (18 patients out of 21) in ESWL, % 94.4 (17 patients out of 18) in RIRS and % 94.7 (18 patients out of 19) in m-PCNL. No difference was observed in the duration of hospitalization among patients who underwent RIRS and m-PCNL. The VAS scores in ESWL group were higher than other groups. There were no significant differences for fluoroscopy time between the groups. Decrease in hemoglobin values before and after the procedure were found to be significant in m-PCNL group (p&lt;0.05).&#x0D; Conclusions: We compared three minimal invasive treatments for less than 2 cm renal stones; m-PCNL and RIRS methods were found to be more effective than ESWL, especially aspects of the stone free rates.

Comparison of Retrograde Intrarenal Surgery and Micro-percutaneous Nephrolithotomy for Kidney Stones 5-10 mm in Diameter

Comparison of Retrograde Intrarenal Surgery and Micro-percutaneous Nephrolithotomy for Kidney Stones 5-10 mm in Diameter

Microperc versus miniperc for the management of medium-sized renal stones: a comparative two-center clinical study

Objective To date, there is very little evidence directly comparing the outcomes between Mini-percutaneous nephrolithotomy and Micro-percutaneous nephrolithotomy. Because of this evidence gap, we wanted to compare miniperc and microperc with an ultimate purpose to determine which modality is preferred for different stone characteristics. Our hope is that these findings may help guide which technique is most suitable for a given renal stone burden. Patients and methods This is a retrospective collaborative multi-institutional study between Dortmund Teaching Hospital (Germany) and Modena University Hospital (Italy) in which we compared two matched groups of patients. The first group (32 patients) underwent miniperc for medium-sized renal stones in Dortmund, and the second group (19 patients) underwent microperc in Modena. Both groups were matched according to age, sex, BMI, and maximum stone diameter according to preoperative plain KUB films. Results The primary stone-free rates in the miniperc and microperc groups were similar (93.8 vs. 84.2%, P = 0.262). Mean operative time for miniperc was significantly shorter than that of microperc (45.6 ± 18.9 vs. 68.7 ± 35.2 min, P = 0.004). The overall complication rate was 11.7%, with no significant difference between the two groups (12.5% for miniperc vs. 10.5% for microperc, P = 0.604). Mean hospital stay in miniperc was significantly longer than that of microperc (4.7 ± 1.6 vs. 3 ± 1.5 days,P Conclusion Our current data show that microperc is emerging as an effective and safe treatment option for intermediate-sized kidney stones, with outcomes comparable even to miniperc, which is already a well-established treatment with high safety profile in experienced hands.