Single-versus multi-tract mini percutaneous nephrolithotomy for renal stones in a solitary kidney: a propensity-matched study

Single-versus multi-tract mini percutaneous nephrolithotomy for renal stones in a solitary kidney: a propensity-matched study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Single-versus multi-tract mini percutaneous nephrolithotomy for renal stones in a solitary kidney: a propensity-matched study Yeci Lei, Shangwen Dou, Gaoyuanzhi Yue, Huacai Zhu, Bangfeng Liu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2663590/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Mini percutaneous nephrolithotomy (mPNL) is recommended for renal stones in a solitary kidney due to its high stone-free rate (SFR), with acceptable complications. Aimed to compare the effectiveness and the safety of single-tract mPNL (SM) and multi-tract mPNL (MM) in these patients. Methods: 176 patients with a solitary kidney who had undergone SM or MM from January 2013 to December 2020 had been retrospectivelyevaluated. The MM group had tractsranged from 2 to 3. Patient clinical characteristics and demographic information were used for propensity score matching (PSM). Both groups' perioperative outcomes, procedure numbers, and efficacy quotient (EQ) were evaluated. As a more objective indicator for stone removal, EQ was calculated by SFR, retreatment rate, and auxiliary procedure rate. Results: The retreatment rate of the SM group was higher than the MM group (45.2% vs 21.4%, P =0.031). No statistical difference between the two groups in complication rate. The initial SFR of the MM group was significantly higher than that of the SM group in a subgroup with a cumulative stone diameter (CSD) range of 40-70 mm (58.8%vs15.4%, P =0.026). The MM group had a significantly lower retreatment rate than SM (23.5% vs 69.2%, P =0.025), showinga higher EQ (56.5% vs 34.8%) and fewer procedures (1.35±0.49 vs 1.77±0.44, P =0.023). Conclusions: In the CSD 40-70mm subgroups,MM proved better EQ with an acceptable complication rate and fewer procedures. When the CSD ranges from 40-70mm, MM can be used as a preferred procedure for renal stones in a solitary kidney. Trial registration: This study was retrospectively registered and approved by the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41) renal stones solitary kidney mini percutaneous nephrolithotomy multi-tracts single-tract Background It is a challenge for urologists to manage the patients with renal stones in a solitary kidney. Since the contralateral kidney is unable to functionally compensate, the impact of any complications will be magnified ( 1 – 3 ). The European Association of Urology guidelines emphasize that to reduce the possibility of stone recurrence, it is paramount to obtain a higher stone-free rate(SFR)( 4 ). However, patients with complex kidney stones often require multiple interventions to ensure complete removal of the stones ( 5 – 7 ), which is obviously not suitable for patients with a solitary kidney. There is a need to strike a balance between the efficiency of stone clearance and patient safety to maximize the benefit to the patients ( 8 , 9 ). Mini percutaneous nephrolithotomy (mPNL) is recommended for this condition due to its high SFR, with an acceptable complication rate ( 10 – 12 ). In our medical center, mPNL is mainly divided into two types: single-tract and multi-tract ( 13 ). It remains a matter of debate which technique is more reasonable to manage stone patients with solitary kidney. In this study, the safety and effectiveness of single-tract and multi-tract mPNL were compared in the management of these patients. Methods Study design This study retrospectively investigated a total of 176 patients with solitary kidney who were treated with single- tract mPNL (SM) or multi-tract mPNL (MM) for renal stones in our institution from January 2013 to December 2020. There were 124 patients in the SM group and 52 in the other group. 50 patients received 2-tracts mPNL and 2 patients received 3-tracts mPNL. Through propensity score matched(PSM)pairing, 42 patients who received SM were paired with 42 patients who received MM. Approval for the study was obtained from the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41). All the patients were diagnosed as solitary kidney through radiological examinations. The types of all confirmed patients are classified into two categories, anatomical and functional solitary kidneys. Anatomically solitary kidneys include congenital renal agenesis, or patients with the history of unilateral nephrectomy. The functional solitary kidney is indicated by helical non-contrast computed tomography (CT) and the split renal function glomerular filtration rate (eGFR) is < 5% on a 99m Tc labeled dimercaptosuccinic acid single-photon emission computed tomography ( 14 ). The following data were recorded: age, gender, body mass index (BMI), cumulative stone diameter (CSD), stone burden, Guy's stone score (GSS) ( 15 ), comorbidities, perioperative outcomes, and complications. The patients included in the study were in the age range of 18–70 years, the eGFR of the kidney on the side of the renal stone was > 20ml/min, and the American Society of Anesthesiology score was 1–2. Patients with morbid obesity, history of kidney transplantation or urinary diversion, uncorrected coagulopathy, or urinary tract infection were excluded. All procedures were performed by an experienced urologist. The surgeon selected the treatment method for each case before the operation based on the complexity of the stone, the comorbidities, anatomy of the renal collecting system and surgical experience. CSD, stone burden, and GSS were all assessed by urologists through CT. CSD was calculated as the total of the maximum diameters in cases with multiple stones. We use the formula: Length x Width x πx 1/4 to account the areas of stones and stone burden was calculated as the sum of the areas of all stones. Hydronephrosis was evaluated by ultrasound ( 16 ). The pre-post Serum creatinine (Scr) value was calculated as postoperative Scr subtracted from preoperative Scr. The decline in hemoglobin (Hb) was defined as the difference between Hb before and within 48–72 hours after surgery. The surgery of mPNL was completed within 3 hours. Patients with no evidence of urinary tract infection were administered prophylactic antibiotics 1 hour before surgery, and those with urinary tract infection confirmed by urine culture were administered sensitive antibiotic treatment until a negative result was obtained from urine culture before the operation. Surgical Technique Each patient was in the lithotomy position under general anesthesia, and first, a 5 Fr ureteral catheter was inserted into the renal pelvis in a retrograde fashion. The patient was then turned into the prone position. Renal puncture was established by an experienced surgeon under either sonographic or fluoroscopy guidance. The tract was dilated with fascial dilators up to 16Fr or 18Fr and the number of tracts in the MM group ranged from 2 to 3. A rigid 8.5/13Fr endoscope was used for the nephroscopy. A pneumatic lithotripter and/or holmium laser (raykeen, 2J*40hz,80w) were used for stone fragmentation. Creating additional access tracts was considered necessary for patients who underwent the planned multi-tract procedure. A 16 Fr nephrostomy tube and a 6 Fr ureteral stent were routinely placed for each patient and removed on the first day and the first week after surgery, respectively. If no obvious bleeding is found during the operation, the tubeless procedure will be performed. Perioperative Outcome Assessment Complications were evaluated according to the modified Clavien classification system ( 17 ). The initial SFR was defined as the absence of any residual stones or presence of residual fragments of 4mm, second-stage mPNL treatment or another auxiliary procedure was performed one week after the first procedure, which was recorded as the patient's retreatment or auxiliary procedures, and the final SFR was assessed one month after the first procedure. The number of procedures was the total number of mPNL received by the patient and the number of other auxiliary procedures. Auxiliary procedures included extracorporeal shockwave lithotripsy(SWL), ureteroscopic lithotripsy (URL), retrograde intrarenal surgery (RIRS). The efficacy quotient (EQ), which is the primary outcome of this study, was calculated using the following equation: EQ= (Stone-free rate/ (100% + Retreatment rate + Auxiliary procedure rate)) *100% ( 19 ). Statistical Analysis The propensity score was estimated for all the patients using binary logistic regression, with age, gender, BMI, CSD, stone burden, GSS, hydronephrosis classification, preoperative urine culture, and preoperative Scr as the dependent variables. The comparisons of continuous variables were made using the Student's t-test or the Mann-Whitney U-test or the Wilcoxon rank-sum test. Categorical variables were compared using the Chi-square or Fisher exact test. Continuous variables were denoted as mean ± standard deviation values, and categorical variables as frequency and percentage. Results were considered statistically significant at p < 0.05. Statistical analysis was performed using SPSS Version 20 software (IBM, Armonk, NY, USA). The analysis was performed using SAS software (SAS Inc., USA) for a case-control match based on the propensity score. Results As shown in Table 1, the two groups were comparable in terms of baseline demographic characteristics, stone characteristics, comorbidities, hydronephrosis classification, etiology of the solitary kidney, and the mean preoperative Scr after matching. All perioperative and postoperative outcomes are displayed in Table 2. There was no statistical significance in the mean postoperative hospital stay (p=0.303), the decline of Hb (p=0.520), and the pre-post Scr (p=0.580) in the SM group and the MM group. The two groups were similar in complication rate(38.1% vs 40.5%, p=0.649，Table 2). No Clavien Grade IV-V complications occurred in either group. In the SM group, one patient developed right pleural effusion and right atelectasis after surgery and required thoracentesis (Clavien Grade Ⅲ). As shown in Table 3. The initial and final SFR of the MM group were higher than those of the SM group, but there was no statistical difference (initial:54.8% vs 42.9%, p=0.454, final: 71.4% vs 64.3%, p=0.815). The retreatment rate of the SM group was higher than that of the MM group (45.2% vs 21.4%, p=0.031). The rate of auxiliary procedures and the number of procedures was similar between the SM and MM group (p=0.763, p=0.085). According to the method mentioned above to calculate the EQ value, the MM group was slightly higher than the SM group（52.6% vs 40.9%). Further analyzed in the subgroups with CSD ≤ 40 mm, 40-70 mm, and＞70 mm. These subgroups were comparable in respect of CSD and stone burden. In the subgroup of CSD ≤40mm, the final SFR of the two group was similar (93.3% vs 90.9%, p=0.956). There was no second-stage mPNL in either group. The initial SFR and final SFR of the MM group were better in the subgroup with CSD ranging from 40-70 mm（initial：58.8% vs 15.4%, p=0.026, final：76.5% vs 61.5%, p=0.443). The SM group showed a higher retreatment rate（69.2% vs 23.5%, p=0.025), but the rate of auxiliary procedures was similar in the two groups. To summarise, in this subgroup, although the final SFR was similar, MM presented a higher EQ (SM vs MM, 56.5% vs 34.8%) than SM, and underwent fewer procedures (1.35±0.49 vs 1.77±0.44, p=0.023). There was no statistical difference between the SM group and the MM group in the subgroup of CSD＞70mm. Discussion The safety and effectiveness of MM and SM have been previously compared ( 13 ), however there were several restrictions on the characteristic data of stones in this research, which leads to inevitable bias. We believe it is insufficient to use SFR as the only indicator of treatment success to evaluate the efficacy of interventions. In theory, patients can reach 100% SFR status through repeated surgical interventions. This would not only indirectly increase the risk of complications, but also increase the burden on patients from different aspects (psychological stress, loss of workload and money) and cause a waste of medical resources. The efficacy quotient (EQ) is a more objective indicator because it takes into account the influencing factors of SFR, the retreatment rate and the auxiliary procedure rate ( 20 ). Thus, EQ is widely used in SWL and the authors thought it was appropriate to introduce EQ into this research. In this study, more comprehensive stone characteristic data were collected, including CSD, stone burden, and GSS. Propensity score matching analysis was performed on these data, and the EQ value was calculated. The EQ values of the single-tract group and the multi-tract group were determined to be 40.9% and 52.6%, respectively. Shi et al. ( 14 ) reported that EQ of PNL for solitary kidney were 76.47%. The difference between the two studies may arise as the stone characteristic enrolled in the current study were more complicated. In the subgroup of CSD ≤ 40mm, the EQ of SM for stones in a solitary kidney was 93.7% compared to 91.7% of MM. Both groups showed a higher rate of stone clearance. Pan et al. reported that EQ of PNL for anatomically normal renal stones of 2–3 cm was 90.4% ( 21 ), which is similar to our study results. Moreover, through subgroup analysis of CSD by 40–70 mm, the initial SFR of the MM group was found to be higher and the retreatment rate was lower. Compared with the SM group, EQ was higher and there were fewer procedures. For both SM and MM group, stones > 70 mm stones showed poor initial SFR and required repeated operations. In general, multi-tract PNL has a higher chance of removing stones completely in a single procedure, but SFR decline as the size of stone increases. When the size of the stone exceeds a certain level, staged procedure should be considered to ensure the successful removal of the stone. ( 22 , 23 ). In a study by Hyuk Jin Cho et al, significant differences were not observed when single-tract PNL was compared with multi-tract PNL in terms of the drop in Hb ( 24 ), and this research is the same. There are inconsistent reports regarding the effects of multi tract PNL on renal function. In the research by Liu, C., et al ( 13 ), the the blood loss of single tract and multi tracts were higher than our data. This may be due to the improvement of technology and statistical methods. Akman et al ( 25 ) compared 413 cases of multi-tract and single-tract PNL and found no significant difference in the average change of Scr between the two groups. Fayad et al ( 26 ) reported that patients with baseline renal impairment (Scr level ≥ 1.4 mg/dL) had worsening Scr and worsening GFR by evaluating the effects of multi-tracts PNL on renal function. No statistically difference was observed between the groups in this study in respect of Scr level (p = 0.580). In this study, the channel size was 16-18F. Recent studies have shown that establishing multiple mini-tract in PNL is safe ( 27 – 29 ). Mini tract can be equally effective in the treatment and might offer the possibility of reducing the degree of variation in Hb and Scr, when compared with standard PNL ( 29 , 30 ). These previous reports may explain the lack of difference between the MM group and SM group in the changes in Hb and Scr. No statistically significant difference was observed between the groups in this study in respect of mean postoperative hospitalization duration (p = 0.303) and complication rates (p = 0.893). Overall, no significant difference was observed between the two groups in safety. This study has certain limitations, primarily the retrospective design and small sample size. Second, the treatment method depends on the patient's co-morbidities, renal anatomic characteristics, as well as the experience of the surgeon, which leads to an inevitable selection bias. Finally, there was a lack of long-term renal function follow-up results of the patients. There is a need for future larger-scale prospective studies to overcome these problems and compare the long-term effects of single-tract mPNL and multi-tract mPNL in the management of solitary kidneys with renal stones. Conclusions Surgical methods should be selected on an individual basis according to the general condition of the patient and surgical experience, with the aim of avoiding serious complications, reducing the number of interventions, and completely removing the renal stones to reduce the possibility of recurrence. The results of this study showed that in the subgroups of CSD range of 40-70mm, the MM group had better efficacy quotient (EQ) of stone removal, with an acceptable complication rate, and fewer procedures. Abbreviations mPNL = Mini percutaneous nephrolithotomy SFR = stone-free rate SM = single-tract mPNL MM = multi-tract mPNL PSM = propensity score matching EQ = efficacy quotient CSD = cumulative stone diameter CT = helical non-contrast computed tomography eGFR = the split renal function glomerular filtration rate GSS = Guy's stone score Hb = hemoglobin SWL = extracorporeal shockwave lithotripsy URL = ureteroscopic lithotripsy RIRS = retrograde intrarenal surgery Scr = Serum creatinine Declarations Ethics approval and consent to participate Approval for this study was granted by the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41) has waived the need of informed consent for thia study. All methods were performed following the relevant guidelines and regulations. Consent for publication Not applicable. Availability of data and materials The datasets use and analysed during the current study are available from the corresponding author on reasonable request. Competing interests The author(s) declare no conflict of interest. Funding This work was supported bu the Guangdong Basic and Applied Basic Research Foundation （2020A1515011461） Authors′ contributions YDL had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.Study concept and design:YDL.Acquistion of data:YCL,SWD,GYZY,HCZ,BFL.Analysis and interpretation of data:YCL,SWD.Drafting of the manuscript:YCL,SWD.Critical revision of manuscript for important intellectual content:YDL.Statistical analysis:YCL.Supervision:YDL.Other:none.All authors read and approved the final manuscript. Acknowledgements Not applicable. Author information Prof Yongda Liu, Department of Urology, The First Affiliated Hospital of Guangzhou Medical University, 151 West Yanjiang Road, Guangzhou, 510120, China. Telephone:+86-20-34287636, Fax: +86-20-34287636, E-mail: [email protected] References Bres-Niewada E. Solitary kidney - a clinical challenge for endourologist. Cent European J Urol. 2016;69(1):96-7. Jones P, Rai BP, Ghosh A, Somani BK. Ureteroscopy for stones in solitary kidney: Preferred not just a standard option. Cent European J Urol. 2016;69(3):314. Gremmo E, Ballanger P, Doré B, Aubert J. Hemorrhagic complications during percutaneous nephrolithotomy. Retrospective studies of 772 cases. Prog Urol. 1999;9(3):460-3. Türk C, Petřík A, Sarica K, Seitz C, Skolarikos A, Straub M, et al. EAU Guidelines on Interventional Treatment for Urolithiasis. Eur Urol. 2016;69(3):475-82. Hammad FT, Kaya M, Kazim E. Pediatric extracorporeal shockwave lithotripsy: its efficiency at various locations in the upper tract. 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Tables Table 1 Demographic and clinical data after Propensity Score Matching (PSM) After PSM (n=84) SM (n=42) MM (n=42) P Age(y)a 55.6±11.1 55.9±10.3 0.899 Gender 1.000 male 25 26 female 17 16 BMI (kg/m2)a 23.4±3.8 23.4±3.8 0.970 HT 12 12 1.000 DM 2 2 1.000 Stone Site 1.000 Left 22 23 Right 20 19 Preoperative serum creatinine (μmol/L)a 165.9±104.6 154.5±73.1 0.523 Preoperative urine culture/ n(%) 15(35.7%) 10(23.8%) 0.359 Cumulative-stone diameter(mm)a 57.3±28.0 56.9±23.2 0.899 Stone burden (mm2)a 1098.0±844.7 1184.9±914.0 0.526 Etiology 0.846 Contralateral nephrectomy 2 2 Congenital renal agenesis 2 1 Functional solitary kidney 38 39 GSS/ n(%) 0.670 Ⅰ 2(4.8) 3(7.1) Ⅱ 21(50.0) 18(42.9) Ⅲ 17(40.5) 18(42.9) Ⅳ 2(4.8) 3(7.1) The number of calyceal Stones(n)a 2.7±1.0 3.0±1.2 0.109 Hydronephrosis classification/ n(%) 0.438 G0 5(11.9) 9(21.4) Mild (G1 or G2) 19(45.2) 18(42.9) Moderate (G3) 13(31.0) 9(21.4) Severe (G4) 5(11.9) 6(14.3) BMI, body mass index. G0=grade 0; G1 = grade 1; G2 = grade 2; G3 = grade 3; G4 = grade 4 SM, single-tract mini percutaneous nephrolithotomy. MM, multi-tracts mini percutaneous nephrolithotomy. HT, Hypertension. DM, diabetes mellitus. GSS, Guy's stone score. a Values are presented as mean ± SD. Table 2 Perioperative data, surgery-associated complications by Clavien Scale Parameters SM group （n=42） MM group （n=42） P Mean postoperative hospitalization Duration (days) a 6.6±4.3 7.5±3.8 0.303 Decline in Hb level (g/L) a 12.4±11.4 13.9±11.1 0.520 Pre–post Scr (mg/dL) a -4.7±31.5 -1.2±22.0 0.580 PNL Clavien-Dindo Complications, n (%) 0.649 Grade I 4(9.5) 8(19.1) Grade II 11(26.2) 9(21.4) Grade III 1(2.4) 0 All 16(38.1) 17(40.5) Complications Classification,n (%) Transient serum creatinine increase (Grade I) 4(9.5) 3(7.1) SIRS requiring additional antibiotics (Grade II) 10(26.2) 9(21.4) Blood transfusion (%) (Grade II) 2(4.8) 2(4.8) a Values are presented as mean ± SD. Hb, hemoglobin. Scr, serum creatinine. Pre-post Scr, preoperative Scr subtracted postoperative Scr Table3 Efficacy of treatment SM group (n=42) MM group (n=42) total ≤40mm (n=15) 40~70mm (n=13) >70mm (n=14) total ≤40mm (n=11) 40~70mm (n=17) >70mm (n=14) CSD (mm) a 57.3±28.0 29.2±9.7 55.3±9.5 89.1±16.6 56.9±23.2 29.3±7.7 52.7±8.9 83.8±10.5 Stone burden (mm 2 ) a 1098.0±844.7 314.4±151.9 1060.1±573.8 1972.6±622.9 1184.9±914.0 385.0±224.8 1023.8±444.0 2008.9±1023.0 Initial stone-free rate/ %(n) 42.9(18) 93.3(14) 15.4(2) § 14.3(2) 54.8 (23) 90.9(10) 58.8(10) § 21.4(3) Final stone-free rate/ %(n) 64.3(27) 100.0(15) 61.5(8) 28.6(4) 71.4(30) 100(11) 76.5(13) 42.9(6) Retreatment rate/ %(n) 45.2(19) § 0 69.2(9) § 71.4(10) 21.4(9) § 0 23.5(4) § 35.7(5) Auxiliary procedures rate/ %(n) 11.9(5) 6.7(1) 7.7(1) 21.4(3) 14.3(6) 9.1(1) 11.8(2) 21.4(3) SWL 0 0 0 0 2.3(1) 0 0 7.1(1) URL 0 0 0 0 0 0 0 0 RIRS 11.9(5) 6.7(1) 7.7(1) 21.4(3) 11.9(5) 9.1(1) 11.8(2) 14.3(2) EQ (%) 40.9 93.7 34.8 14.8 52.6 91.7 56.5 27.3 Number of procedures a 1.60±0.63 1.07±0.26 1.77±0.44 ＊ 2.00±0.98 1.38±0.49 1.09±0.30 1.35±0.49 ＊ 1.57 ±0.51 CSD, cumulative stone diameter; EQ, Efficacy quotient ＊ P<0.05(SM vs MM) Student's t-test ＃ P<0.05 (SM vs MM) the Mann-Whitney U test § P<0.05 (SM vs MM) Fisher exact probability a Values are presented as mean ± SD. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2663590","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":184840154,"identity":"bcfcf1fe-760c-4b0a-a9bc-dd99522c1d0d","order_by":0,"name":"Yeci Lei","email":"","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yeci","middleName":"","lastName":"Lei","suffix":""},{"id":184840155,"identity":"29c754be-d1a8-4fe2-a436-b5002f195f85","order_by":1,"name":"Shangwen Dou","email":"","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shangwen","middleName":"","lastName":"Dou","suffix":""},{"id":184840156,"identity":"8ac16317-274e-4735-8c7b-8fd29cdffee2","order_by":2,"name":"Gaoyuanzhi Yue","email":"","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Gaoyuanzhi","middleName":"","lastName":"Yue","suffix":""},{"id":184840157,"identity":"a8975af3-bd46-454b-ba12-7661c41e1785","order_by":3,"name":"Huacai Zhu","email":"","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Huacai","middleName":"","lastName":"Zhu","suffix":""},{"id":184840158,"identity":"1240cb68-b1ce-4c06-9799-890d1ad1e676","order_by":4,"name":"Bangfeng Liu","email":"","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Bangfeng","middleName":"","lastName":"Liu","suffix":""},{"id":184840159,"identity":"b9435fe7-ece0-461b-9aa0-f4be7bd08ba8","order_by":5,"name":"Yongda Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1ElEQVRIiWNgGAWjYBACPmYgwcPAIAcmgYCxgZAWNqgWYxK0MEC0JDYQr4Wdx0zibdu99Pn+Z49u5mGwkd1wgPnZA/wO4zGTnNtWnLvxwLm02zwMacYbDrCZGxDSIs3blpC7sbHHDKjlcOKGAzxsEsRoSTds5gFp+U+8lgR5NrCWA8RoYSu2nHMuwXADD4/ZzTkGycYzD7OZ4dXCz3944403ZQny8v1nzG68qbCT7Tve/AyvFiBgASswOAAmgZiZgHqQkg8gUr6BsMpRMApGwSgYoQAAEjw/B9gtVO4AAAAASUVORK5CYII=","orcid":"","institution":"The First Affiliated Hospital of Guangzhou Medical University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Yongda","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2023-03-07 05:44:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2663590/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2663590/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":35799552,"identity":"519af110-4f93-4e05-9524-6abebab25c28","added_by":"auto","created_at":"2023-04-15 07:44:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":267189,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2663590/v1/11700779-86fd-484d-a8fb-5d7f82da07f1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Single-versus multi-tract mini percutaneous nephrolithotomy for renal stones in a solitary kidney: a propensity-matched study","fulltext":[{"header":"Background","content":"\u003cp\u003eIt is a challenge for urologists to manage the patients with renal stones in a solitary kidney. Since the contralateral kidney is unable to functionally compensate, the impact of any complications will be magnified (\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). The European Association of Urology guidelines emphasize that to reduce the possibility of stone recurrence, it is paramount to obtain a higher stone-free rate(SFR)(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). However, patients with complex kidney stones often require multiple interventions to ensure complete removal of the stones (\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e), which is obviously not suitable for patients with a solitary kidney. There is a need to strike a balance between the efficiency of stone clearance and patient safety to maximize the benefit to the patients (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Mini percutaneous nephrolithotomy (mPNL) is recommended for this condition due to its high SFR, with an acceptable complication rate (\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). In our medical center, mPNL is mainly divided into two types: single-tract and multi-tract (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). It remains a matter of debate which technique is more reasonable to manage stone patients with solitary kidney. In this study, the safety and effectiveness of single-tract and multi-tract mPNL were compared in the management of these patients.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eThis study retrospectively investigated a total of 176 patients with solitary kidney who were treated with single- tract mPNL (SM) or multi-tract mPNL (MM) for renal stones in our institution from January 2013 to December 2020. There were 124 patients in the SM group and 52 in the other group. 50 patients received 2-tracts mPNL and 2 patients received 3-tracts mPNL. Through propensity score matched(PSM)pairing, 42 patients who received SM were paired with 42 patients who received MM. Approval for the study was obtained from the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41). All the patients were diagnosed as solitary kidney through radiological examinations. The types of all confirmed patients are classified into two categories, anatomical and functional solitary kidneys. Anatomically solitary kidneys include congenital renal agenesis, or patients with the history of unilateral nephrectomy. The functional solitary kidney is indicated by helical non-contrast computed tomography (CT) and the split renal function glomerular filtration rate (eGFR) is \u0026lt;\u0026thinsp;5% on a 99m Tc labeled dimercaptosuccinic acid single-photon emission computed tomography (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe following data were recorded: age, gender, body mass index (BMI), cumulative stone diameter (CSD), stone burden, Guy's stone score (GSS) (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e), comorbidities, perioperative outcomes, and complications. The patients included in the study were in the age range of 18\u0026ndash;70 years, the eGFR of the kidney on the side of the renal stone was \u0026gt;\u0026thinsp;20ml/min, and the American Society of Anesthesiology score was 1\u0026ndash;2. Patients with morbid obesity, history of kidney transplantation or urinary diversion, uncorrected coagulopathy, or urinary tract infection were excluded. All procedures were performed by an experienced urologist. The surgeon selected the treatment method for each case before the operation based on the complexity of the stone, the comorbidities, anatomy of the renal collecting system and surgical experience. CSD, stone burden, and GSS were all assessed by urologists through CT. CSD was calculated as the total of the maximum diameters in cases with multiple stones. We use the formula: Length x Width x πx 1/4 to account the areas of stones and stone burden was calculated as the sum of the areas of all stones. Hydronephrosis was evaluated by ultrasound (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). The pre-post Serum creatinine (Scr) value was calculated as postoperative Scr subtracted from preoperative Scr. The decline in hemoglobin (Hb) was defined as the difference between Hb before and within 48\u0026ndash;72 hours after surgery. The surgery of mPNL was completed within 3 hours. Patients with no evidence of urinary tract infection were administered prophylactic antibiotics 1 hour before surgery, and those with urinary tract infection confirmed by urine culture were administered sensitive antibiotic treatment until a negative result was obtained from urine culture before the operation.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSurgical Technique\u003c/h3\u003e\n\u003cp\u003eEach patient was in the lithotomy position under general anesthesia, and first, a 5 Fr ureteral catheter was inserted into the renal pelvis in a retrograde fashion. The patient was then turned into the prone position. Renal puncture was established by an experienced surgeon under either sonographic or fluoroscopy guidance. The tract was dilated with fascial dilators up to 16Fr or 18Fr and the number of tracts in the MM group ranged from 2 to 3. A rigid 8.5/13Fr endoscope was used for the nephroscopy. A pneumatic lithotripter and/or holmium laser (raykeen, 2J*40hz,80w) were used for stone fragmentation. Creating additional access tracts was considered necessary for patients who underwent the planned multi-tract procedure. A 16 Fr nephrostomy tube and a 6 Fr ureteral stent were routinely placed for each patient and removed on the first day and the first week after surgery, respectively. If no obvious bleeding is found during the operation, the tubeless procedure will be performed.\u003c/p\u003e\n\u003ch3\u003ePerioperative Outcome Assessment\u003c/h3\u003e\n\u003cp\u003eComplications were evaluated according to the modified Clavien classification system (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). The initial SFR was defined as the absence of any residual stones or presence of residual fragments of \u0026lt;\u0026thinsp;4mm determined on plain X-radiograph review within 24\u0026ndash;48 hours after surgery(\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). If the largest diameter of a single residual stones is \u0026gt;\u0026thinsp;4mm, second-stage mPNL treatment or another auxiliary procedure was performed one week after the first procedure, which was recorded as the patient's retreatment or auxiliary procedures, and the final SFR was assessed one month after the first procedure. The number of procedures was the total number of mPNL received by the patient and the number of other auxiliary procedures. Auxiliary procedures included extracorporeal shockwave lithotripsy(SWL), ureteroscopic lithotripsy (URL), retrograde intrarenal surgery (RIRS). The efficacy quotient (EQ), which is the primary outcome of this study, was calculated using the following equation: EQ= (Stone-free rate/ (100% + Retreatment rate\u0026thinsp;+\u0026thinsp;Auxiliary procedure rate)) *100% (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e).\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eThe propensity score was estimated for all the patients using binary logistic regression, with age, gender, BMI, CSD, stone burden, GSS, hydronephrosis classification, preoperative urine culture, and preoperative Scr as the dependent variables. The comparisons of continuous variables were made using the Student's t-test or the Mann-Whitney U-test or the Wilcoxon rank-sum test. Categorical variables were compared using the Chi-square or Fisher exact test. Continuous variables were denoted as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation values, and categorical variables as frequency and percentage. Results were considered statistically significant at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Statistical analysis was performed using SPSS Version 20 software (IBM, Armonk, NY, USA). The analysis was performed using SAS software (SAS Inc., USA) for a case-control match based on the propensity score.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eAs shown in Table 1, the two groups were comparable in terms of baseline demographic characteristics, stone characteristics, comorbidities, hydronephrosis classification, etiology of the solitary kidney, and the mean preoperative Scr after matching.\u003c/p\u003e\n\u003cp\u003eAll perioperative and postoperative outcomes are displayed in Table 2. There was no statistical significance in the mean postoperative hospital stay (p=0.303), the decline of Hb (p=0.520), and the pre-post Scr (p=0.580) in the SM group and the MM group. The two groups were similar in complication rate(38.1% vs 40.5%, p=0.649，Table 2). No Clavien Grade IV-V complications occurred in either group. In the SM group, one patient developed right pleural effusion and right atelectasis after surgery and required thoracentesis (Clavien Grade Ⅲ).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs shown in Table 3. The initial and final SFR of the MM group were higher than those of the SM group, but there was no statistical difference (initial:54.8% vs 42.9%, p=0.454, final: 71.4% vs 64.3%, p=0.815). The retreatment rate of the SM group was higher than that of the MM group (45.2% vs 21.4%, p=0.031). The rate of auxiliary procedures and the number of procedures was similar between the SM and MM group (p=0.763, p=0.085). According to the method mentioned above to calculate the EQ value, the MM group was slightly higher than the SM group（52.6% vs 40.9%).\u003c/p\u003e\n\u003cp\u003eFurther analyzed in the subgroups with CSD \u0026le; 40 mm, 40-70 mm, and＞70 mm. These subgroups were comparable in respect of CSD and stone burden. In the subgroup of CSD \u0026le;40mm, the final SFR of the two group was similar (93.3% vs 90.9%, p=0.956). There was no second-stage mPNL in either group. The initial SFR and final SFR of the MM group were better in the subgroup with CSD ranging from 40-70 mm（initial：58.8% vs 15.4%, p=0.026, final：76.5% vs 61.5%, p=0.443). The SM group showed a higher retreatment rate（69.2% vs 23.5%, p=0.025), but the rate of auxiliary procedures was similar in the two groups. To summarise, in this subgroup, although the final SFR was similar, MM presented a higher EQ (SM vs MM, 56.5% vs 34.8%) than SM, and underwent fewer procedures (1.35\u0026plusmn;0.49 vs 1.77\u0026plusmn;0.44, p=0.023). There was no statistical difference between the SM group and the MM group in the subgroup of CSD＞70mm.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe safety and effectiveness of MM and SM have been previously compared (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e), however there were several restrictions on the characteristic data of stones in this research, which leads to inevitable bias. We believe it is insufficient to use SFR as the only indicator of treatment success to evaluate the efficacy of interventions. In theory, patients can reach 100% SFR status through repeated surgical interventions. This would not only indirectly increase the risk of complications, but also increase the burden on patients from different aspects (psychological stress, loss of workload and money) and cause a waste of medical resources. The efficacy quotient (EQ) is a more objective indicator because it takes into account the influencing factors of SFR, the retreatment rate and the auxiliary procedure rate (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). Thus, EQ is widely used in SWL and the authors thought it was appropriate to introduce EQ into this research.\u003c/p\u003e \u003cp\u003eIn this study, more comprehensive stone characteristic data were collected, including CSD, stone burden, and GSS. Propensity score matching analysis was performed on these data, and the EQ value was calculated. The EQ values of the single-tract group and the multi-tract group were determined to be 40.9% and 52.6%, respectively. Shi et al. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) reported that EQ of PNL for solitary kidney were 76.47%. The difference between the two studies may arise as the stone characteristic enrolled in the current study were more complicated. In the subgroup of CSD\u0026thinsp;\u0026le;\u0026thinsp;40mm, the EQ of SM for stones in a solitary kidney was 93.7% compared to 91.7% of MM. Both groups showed a higher rate of stone clearance. Pan et al. reported that EQ of PNL for anatomically normal renal stones of 2\u0026ndash;3 cm was 90.4% (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e), which is similar to our study results. Moreover, through subgroup analysis of CSD by 40\u0026ndash;70 mm, the initial SFR of the MM group was found to be higher and the retreatment rate was lower. Compared with the SM group, EQ was higher and there were fewer procedures. For both SM and MM group, stones\u0026thinsp;\u0026gt;\u0026thinsp;70 mm stones showed poor initial SFR and required repeated operations. In general, multi-tract PNL has a higher chance of removing stones completely in a single procedure, but SFR decline as the size of stone increases. When the size of the stone exceeds a certain level, staged procedure should be considered to ensure the successful removal of the stone. (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn a study by Hyuk Jin Cho et al, significant differences were not observed when single-tract PNL was compared with multi-tract PNL in terms of the drop in Hb (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e), and this research is the same. There are inconsistent reports regarding the effects of multi tract PNL on renal function. In the research by Liu, C., et al (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e), the the blood loss of single tract and multi tracts were higher than our data. This may be due to the improvement of technology and statistical methods. Akman et al (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e) compared 413 cases of multi-tract and single-tract PNL and found no significant difference in the average change of Scr between the two groups. Fayad et al (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e) reported that patients with baseline renal impairment (Scr level\u0026thinsp;\u0026ge;\u0026thinsp;1.4 mg/dL) had worsening Scr and worsening GFR by evaluating the effects of multi-tracts PNL on renal function. No statistically difference was observed between the groups in this study in respect of Scr level (p\u0026thinsp;=\u0026thinsp;0.580). In this study, the channel size was 16-18F. Recent studies have shown that establishing multiple mini-tract in PNL is safe (\u003cspan additionalcitationids=\"CR28\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e). Mini tract can be equally effective in the treatment and might offer the possibility of reducing the degree of variation in Hb and Scr, when compared with standard PNL (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e). These previous reports may explain the lack of difference between the MM group and SM group in the changes in Hb and Scr. No statistically significant difference was observed between the groups in this study in respect of mean postoperative hospitalization duration (p\u0026thinsp;=\u0026thinsp;0.303) and complication rates (p\u0026thinsp;=\u0026thinsp;0.893). Overall, no significant difference was observed between the two groups in safety.\u003c/p\u003e \u003cp\u003eThis study has certain limitations, primarily the retrospective design and small sample size. Second, the treatment method depends on the patient's co-morbidities, renal anatomic characteristics, as well as the experience of the surgeon, which leads to an inevitable selection bias. Finally, there was a lack of long-term renal function follow-up results of the patients. There is a need for future larger-scale prospective studies to overcome these problems and compare the long-term effects of single-tract mPNL and multi-tract mPNL in the management of solitary kidneys with renal stones.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eSurgical methods should be selected on an individual basis according to the general condition of the patient and surgical experience, with the aim of avoiding serious complications, reducing the number of interventions, and completely removing the renal stones to reduce the possibility of recurrence. The results of this study showed that in the subgroups of CSD range of 40-70mm, the MM group had better efficacy quotient (EQ) of stone removal, with an acceptable complication rate, and fewer procedures.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003emPNL = Mini percutaneous nephrolithotomy\u003c/p\u003e\n\u003cp\u003eSFR = stone-free rate\u003c/p\u003e\n\u003cp\u003eSM = single-tract mPNL\u003c/p\u003e\n\u003cp\u003eMM = multi-tract mPNL\u003c/p\u003e\n\u003cp\u003ePSM = propensity score matching\u003c/p\u003e\n\u003cp\u003eEQ = efficacy quotient\u003c/p\u003e\n\u003cp\u003eCSD = cumulative stone diameter\u003c/p\u003e\n\u003cp\u003eCT = helical non-contrast computed tomography\u003c/p\u003e\n\u003cp\u003eeGFR = the split renal function glomerular filtration rate\u003c/p\u003e\n\u003cp\u003eGSS = Guy\u0026apos;s stone score\u003c/p\u003e\n\u003cp\u003eHb = hemoglobin\u003c/p\u003e\n\u003cp\u003eSWL = extracorporeal shockwave lithotripsy\u003c/p\u003e\n\u003cp\u003eURL = ureteroscopic lithotripsy\u003c/p\u003e\n\u003cp\u003eRIRS = retrograde intrarenal surgery\u003c/p\u003e\n\u003cp\u003eScr = Serum creatinine\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eApproval for this study was granted by the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41) has waived the need of informed consent for thia study. All methods were performed following the relevant guidelines and regulations.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets use and analysed during the current study are available from the corresponding author on reasonable request.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author(s) declare no conflict of interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported bu the Guangdong Basic and Applied Basic Research Foundation （2020A1515011461）\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAuthors\u0026prime; contributions\u003c/p\u003e\n\u003cp\u003eYDL had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.Study concept and design:YDL.Acquistion of data:YCL,SWD,GYZY,HCZ,BFL.Analysis and interpretation of data:YCL,SWD.Drafting of the manuscript:YCL,SWD.Critical revision of manuscript for important intellectual content:YDL.Statistical analysis:YCL.Supervision:YDL.Other:none.All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eProf Yongda Liu, Department of \u0026nbsp;Urology, The First Affiliated Hospital of Guangzhou Medical University, 151 West Yanjiang Road, Guangzhou, 510120, China. Telephone:+86-20-34287636, Fax: +86-20-34287636, E-mail: [email protected]\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBres-Niewada E. Solitary kidney - a clinical challenge for endourologist. Cent European J Urol. 2016;69(1):96-7. \u003c/li\u003e\n\u003cli\u003eJones P, Rai BP, Ghosh A, Somani BK. Ureteroscopy for stones in solitary kidney: Preferred not just a standard option. Cent European J Urol. 2016;69(3):314. \u003c/li\u003e\n\u003cli\u003eGremmo E, Ballanger P, Dor\u0026eacute; B, Aubert J. Hemorrhagic complications during percutaneous nephrolithotomy. Retrospective studies of 772 cases. Prog Urol. 1999;9(3):460-3. \u003c/li\u003e\n\u003cli\u003eT\u0026uuml;rk C, Petř\u0026iacute;k A, Sarica K, Seitz C, Skolarikos A, Straub M, et al. EAU Guidelines on Interventional Treatment for Urolithiasis. Eur Urol. 2016;69(3):475-82.\u003c/li\u003e\n\u003cli\u003eHammad FT, Kaya M, Kazim E. Pediatric extracorporeal shockwave lithotripsy: its efficiency at various locations in the upper tract. J Endourol. 2009;23(2):229-35. \u003c/li\u003e\n\u003cli\u003eLiang T, Zhao C, Wu G, Tang B, Luo X, Lu S, et al. Multi-tract percutaneous nephrolithotomy combined with EMS lithotripsy for bilateral complex renal stones: our experience. BMC Urol. 2017;17(1):15. \u003c/li\u003e\n\u003cli\u003eTorricelli FCM, Monga M. Staghorn renal stones: what the urologist needs to know. Int Braz J Urol. 2020;46(6):927-33. \u003c/li\u003e\n\u003cli\u003eDanilovic A, Torricelli FCM, Marchini GS, Batagello C, Vicentini FC, Traxer O, et al. Does previous standard percutaneous nephrolithotomy impair retrograde intrarenal surgery outcomes? Int Braz J Urol. 2021;47(6):1198-206. \u003c/li\u003e\n\u003cli\u003ePietropaolo A, Reeves T, Aboumarzouk O, Kallidonis P, Ozsoy M, Skolarikos A, et al. 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. J Endourol. 2020;34(1):7-17. \u003c/li\u003e\n\u003cli\u003eZeng G, Zhao Z, Wan S, Mai Z, Wu W, Zhong W, et al. Minimally invasive percutaneous nephrolithotomy for simple and complex renal caliceal stones: a comparative analysis of more than 10,000 cases. J Endourol. 2013;27(10):1203-8. \u003c/li\u003e\n\u003cli\u003eZeng G, Zhu W, Li J, Zhao Z, Zeng T, Liu C, et al. The comparison of minimally invasive percutaneous nephrolithotomy and retrograde intrarenal surgery for stones larger than 2 cm in patients with a solitary kidney: a matched-pair analysis. World J Urol. 2015;33:1159-64. \u003c/li\u003e\n\u003cli\u003eBotelho Y, Marchini GS, Monga M, Torricelli FC, Danilovic A, Vicentini FC, et al. Prone split-leg endoscopic-guided percutaneous nephrolithotomy: the surgeons perspective with A Gopro\u0026reg; view. Int Braz J Urol. 2021;47(3):680-1. \u003c/li\u003e\n\u003cli\u003eLiu C, Cui Z, Zeng G, Wan SP, Li J, Zhu W, et al. The optimal minimally invasive percutaneous nephrolithotomy strategy for the treatment of staghorn stones in a solitary kidney. Urolithiasis. 2016;44(2):149-54. \u003c/li\u003e\n\u003cli\u003eShi X, Peng Y, Li X, Wang Q, Li L, Liu M, et al. Propensity score-matched analysis comparing retrograde intrarenal surgery with percutaneous nephrolithotomy for large stones in patients with a solitary kidney. J Endourol. 2018;32(3):198-204. \u003c/li\u003e\n\u003cli\u003eThomas K, Smith NC, Hegarty N, Glass JM. The Guy\u0026apos;s stone score--grading the complexity of percutaneous nephrolithotomy procedures. Urology. 2011;78(2):277-81. \u003c/li\u003e\n\u003cli\u003eJung J, Lee JH, Kim KS, Park YS. Utility of society for fetal urology and anteroposterior pelvic diameter grading systems for estimating time to resolution of isolated hydronephrosis: A single center study. J Urol. 2020;204(5):1048-53. \u003c/li\u003e\n\u003cli\u003eTefekli A, Ali Karadag M, Tepeler K, Sari E, Berberoglu Y, Baykal M, et al. Classification of percutaneous nephrolithotomy complications using the modified clavien grading system: looking for a standard. Eur Urol. 2008;53(1):184-90. \u003c/li\u003e\n\u003cli\u003eOpondo D, Gravas S, Joyce A, Pearle M, Matsuda T, Sun YH, et al. Standardization of patient outcomes reporting in percutaneous nephrolithotomy. J Endourol. 2014;28(7):767-74. \u003c/li\u003e\n\u003cli\u003eDenstedt J, Clayman RV, Preminger G. Efficiency quotient as a means of comparing lithotripters. J Endourol. 1990;4:100. \u003c/li\u003e\n\u003cli\u003eKurien A, Symons S, Manohar T, Desai M. Extracorporeal shock wave lithotripsy in children: equivalent clearance rates to adults is achieved with fewer and lower energy shock waves. BJU Int. 2009;103(1):81-4. \u003c/li\u003e\n\u003cli\u003ePan J, Chen Q, Xue W, Chen Y, Xia L, Chen H, et al. RIRS versus mPCNL for single renal stone of 2-3 cm: clinical outcome and cost-effective analysis in Chinese medical setting. Urolithiasis. 2013;41(1):73-8. \u003c/li\u003e\n\u003cli\u003eGhani KR, Andonian S, Bultitude M, Desai M, Giusti G, Okhunov Z, et al. Percutaneous Nephrolithotomy: Update, Trends, and Future Directions. Eur Urol. 2016;70(2):382-96. \u003c/li\u003e\n\u003cli\u003eBalaji S, Ganpule A, Herrmann T, Sabnis R, Desai M. Contemporary role of multi-tract percutaneous nephrolithotomy in the treatment of complex renal calculi. Asian J Urol. 2020;7(2):102-9. \u003c/li\u003e\n\u003cli\u003eCho HJ, Lee JY, Kim SW, Hwang TK, Hong SH. Percutaneous nephrolithotomy for complex renal calculi: is multi-tract approach ok? Can J Urol. 2012;19(4):6360-5. \u003c/li\u003e\n\u003cli\u003eAkman T, Sari E, Binbay M, Yuruk E, Tepeler A, Kaba M, et al. Comparison of outcomes after percutaneous nephrolithotomy of staghorn calculi in those with single and multiple accesses. J Endourol. 2010;24(6):955-60. \u003c/li\u003e\n\u003cli\u003eFayad AS, Elsheikh MG, Mosharafa A, El-Sergany R, Abdel-Rassoul MA, Elshenofy A, et al. Effect of multiple access tracts during percutaneous nephrolithotomy on renal function: evaluation of risk factors for renal function deterioration. J Endourol. 2014;28(7):775-9. \u003c/li\u003e\n\u003cli\u003eHanda RK, Evan AP, Willis LR, Johnson CD, Connors BA, Gao S, et al. Renal functional effects of multiple-tract percutaneous access. J Endourol. 2009;23(12):1951-6. \u003c/li\u003e\n\u003cli\u003eHeinze A, Gozen AS, Rassweiler J. Tract sizes in percutaneous nephrolithotomy: does miniaturization improve outcome? Curr Opin Urol. 2019;29(2):118-23. \u003c/li\u003e\n\u003cli\u003eZhou Y, Gurioli A, Luo J, Li Z, Zhu J, Li J, et al. Comparison of effect of minimally invasive percutaneous nephrolithotomy on split renal function: Single tract vs multiple tracts. J Endourol. 2017;31(4):361-5. \u003c/li\u003e\n\u003cli\u003eJiao B, Luo Z, Huang T, Zhang G, Yu J. A systematic review and meta-analysis of minimally invasive vs. standard percutaneous nephrolithotomy in the surgical management of renal stones. Exp Ther Med. 2021;21(3):213.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 Demographic and clinical data after Propensity Score Matching (PSM)\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" width=\"40.27303754266212%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" width=\"59.72696245733788%\"\u003e\n \u003cp\u003eAfter PSM (n=84)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"35.142857142857146%\"\u003e\n \u003cp\u003eSM (n=42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"32.285714285714285%\"\u003e\n \u003cp\u003eMM (n=42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"32.57142857142857%\"\u003e\n \u003cp\u003eP\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eAge(y)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e55.6\u0026plusmn;11.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e55.9\u0026plusmn;10.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.899\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003emale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003efemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eBMI (kg/m2)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e23.4\u0026plusmn;3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e23.4\u0026plusmn;3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.970\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eHT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eDM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eStone\u0026nbsp;Site\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eLeft\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eRight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003ePreoperative\u0026nbsp;serum creatinine\u0026nbsp;(\u0026mu;mol/L)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e165.9\u0026plusmn;104.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e154.5\u0026plusmn;73.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.523\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003ePreoperative\u0026nbsp;urine\u0026nbsp;culture/ n(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e15(35.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e10(23.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.359\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eCumulative-stone diameter(mm)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e57.3\u0026plusmn;28.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e56.9\u0026plusmn;23.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.899\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eStone burden\u0026nbsp;(mm2)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e1098.0\u0026plusmn;844.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e1184.9\u0026plusmn;914.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.526\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eEtiology\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.846\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eContralateral\u0026nbsp;nephrectomy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eCongenital renal agenesis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eFunctional\u0026nbsp;solitary\u0026nbsp;kidney\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eGSS/ n(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.670\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eⅠ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2(4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e3(7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eⅡ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e21(50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e18(42.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eⅢ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e17(40.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e18(42.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eⅣ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2(4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e3(7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eThe number of calyceal Stones(n)a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e2.7\u0026plusmn;1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e3.0\u0026plusmn;1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.109\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eHydronephrosis\u0026nbsp;classification/ n(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e0.438\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eG0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e5(11.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e9(21.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eMild (G1 or G2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e19(45.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e18(42.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eModerate (G3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e13(31.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e9(21.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.27303754266212%\"\u003e\n \u003cp\u003eSevere (G4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.9285%;\" width=\"20.98976109215017%\"\u003e\n \u003cp\u003e5(11.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.8041%;\" width=\"19.283276450511945%\"\u003e\n \u003cp\u003e6(14.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.6333%;\" width=\"19.453924914675767%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eBMI, body mass index. G0=grade 0; G1 = grade 1; G2 = grade 2; G3 = grade 3; G4 = grade 4\u003c/p\u003e\n\u003cp\u003eSM, single-tract mini percutaneous nephrolithotomy. MM, multi-tracts mini percutaneous nephrolithotomy. HT, Hypertension. DM, diabetes mellitus. GSS, Guy\u0026apos;s stone score.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003eValues are presented as mean \u0026plusmn; SD.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Perioperative data, surgery-associated complications by Clavien Scale\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\" width=\"548\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eParameters\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003eSM group \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e（n=42）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003eMM group\u003c/p\u003e\n \u003cp\u003e（n=42）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eMean postoperative hospitalization\u003c/p\u003e\n \u003cp\u003eDuration (days)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e6.6\u0026plusmn;4.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e7.5\u0026plusmn;3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e0.303\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eDecline in Hb level (g/L)\u003csup\u003ea\u003c/sup\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e12.4\u0026plusmn;11.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e13.9\u0026plusmn;11.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e0.520\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003ePre\u0026ndash;post Scr (mg/dL)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e-4.7\u0026plusmn;31.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e-1.2\u0026plusmn;22.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e0.580\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003ePNL Clavien-Dindo Complications, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e0.649\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eGrade I\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e4(9.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e8(19.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eGrade II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e11(26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e9(21.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eGrade III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e1(2.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eAll\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e16(38.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e17(40.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eComplications Classification,n (%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eTransient serum creatinine increase (Grade I)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e4(9.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e3(7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eSIRS requiring additional antibiotics (Grade II)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e10(26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e9(21.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"58.57664233576642%\"\u003e\n \u003cp\u003eBlood transfusion (%) (Grade II)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.145985401459853%\"\u003e\n \u003cp\u003e2(4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.605839416058394%\"\u003e\n \u003cp\u003e2(4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.671532846715328%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003eValues are presented as mean \u0026plusmn; SD.\u003c/p\u003e\n\u003cp\u003eHb, hemoglobin. Scr, serum creatinine.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePre-post Scr, preoperative Scr subtracted postoperative Scr\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable3\u003c/strong\u003e Efficacy of treatment\u0026nbsp;\u003c/p\u003e\n \u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\" width=\"923\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" width=\"20.88744588744589%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" width=\"39.17748917748918%\"\u003e\n \u003cp\u003eSM group\u003c/p\u003e\n \u003cp\u003e(n=42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" width=\"39.935064935064936%\"\u003e\n \u003cp\u003eMM group\u003c/p\u003e\n \u003cp\u003e(n=42)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"12.62002743484225%\"\u003e\n \u003cp\u003etotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"11.659807956104252%\"\u003e\n \u003cp\u003e\u0026le;40mm\u003c/p\u003e\n \u003cp\u003e(n=15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"12.62002743484225%\"\u003e\n \u003cp\u003e40~70mm\u003c/p\u003e\n \u003cp\u003e(n=13)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"12.62002743484225%\"\u003e\n \u003cp\u003e\u0026gt;70mm\u003c/p\u003e\n \u003cp\u003e(n=14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"12.62002743484225%\"\u003e\n \u003cp\u003etotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"11.659807956104252%\"\u003e\n \u003cp\u003e\u0026le;40mm\u003c/p\u003e\n \u003cp\u003e(n=11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"12.62002743484225%\"\u003e\n \u003cp\u003e40~70mm\u003c/p\u003e\n \u003cp\u003e(n=17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.580246913580247%\"\u003e\n \u003cp\u003e\u0026gt;70mm\u003c/p\u003e\n \u003cp\u003e(n=14)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eCSD (mm)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e57.3\u0026plusmn;28.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e29.2\u0026plusmn;9.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e55.3\u0026plusmn;9.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e89.1\u0026plusmn;16.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e56.9\u0026plusmn;23.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e29.3\u0026plusmn;7.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e52.7\u0026plusmn;8.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e83.8\u0026plusmn;10.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eStone burden (mm\u003csup\u003e2\u003c/sup\u003e)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1098.0\u0026plusmn;844.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e314.4\u0026plusmn;151.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1060.1\u0026plusmn;573.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1972.6\u0026plusmn;622.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1184.9\u0026plusmn;914.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e385.0\u0026plusmn;224.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1023.8\u0026plusmn;444.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e2008.9\u0026plusmn;1023.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eInitial stone-free rate/ %(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e42.9(18)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e93.3(14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e15.4(2)\u003csup\u003e\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e14.3(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e54.8 (23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e90.9(10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e58.8(10)\u003csup\u003e\u0026nbsp;\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e21.4(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eFinal stone-free rate/ %(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e64.3(27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e100.0(15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e61.5(8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e28.6(4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e71.4(30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e100(11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e76.5(13)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e42.9(6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eRetreatment rate/ %(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e45.2(19)\u003csup\u003e\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e69.2(9)\u003csup\u003e\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e71.4(10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e21.4(9)\u003csup\u003e\u0026nbsp;\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e23.5(4)\u003csup\u003e\u0026nbsp;\u0026sect;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e35.7(5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eAuxiliary procedures rate/ %(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e11.9(5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e6.7(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e7.7(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e21.4(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e14.3(6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e9.1(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e11.8(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e21.4(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eSWL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e2.3(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e7.1(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eURL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eRIRS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e11.9(5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e6.7(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e7.7(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e21.4(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e11.9(5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e9.1(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e11.8(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e14.3(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eEQ (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e40.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e93.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e34.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e14.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e52.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e91.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e56.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e27.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"20.932754880694144%\"\u003e\n \u003cp\u003eNumber of procedures\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1.60\u0026plusmn;0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e1.07\u0026plusmn;0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1.77\u0026plusmn;0.44\u003csup\u003e＊\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e2.00\u0026plusmn;0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1.38\u0026plusmn;0.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.219088937093275%\"\u003e\n \u003cp\u003e1.09\u0026plusmn;0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"9.97830802603037%\"\u003e\n \u003cp\u003e1.35\u0026plusmn;0.49\u003csup\u003e＊\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"10.737527114967461%\"\u003e\n \u003cp\u003e1.57 \u0026plusmn;0.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eCSD, cumulative stone diameter; EQ, Efficacy quotient\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e＊\u003c/sup\u003eP\u0026lt;0.05(SM vs MM) Student\u0026apos;s t-test\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e＃\u003c/sup\u003eP\u0026lt;0.05 (SM vs MM) the Mann-Whitney U test\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e\u0026sect;\u003c/sup\u003eP\u0026lt;0.05 (SM vs MM) Fisher exact probability \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003eValues are presented as mean \u0026plusmn; SD.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"renal stones, solitary kidney, mini percutaneous nephrolithotomy, multi-tracts, single-tract","lastPublishedDoi":"10.21203/rs.3.rs-2663590/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2663590/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eMini percutaneous nephrolithotomy (mPNL) is recommended for renal stones in a solitary kidney due to its high stone-free rate (SFR), with acceptable complications. Aimed to compare the effectiveness and the safety of single-tract mPNL (SM) and multi-tract mPNL (MM) in these patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003e176 patients with a solitary kidney who had undergone SM or MM from January 2013 to December 2020 had been retrospectivelyevaluated. The MM group had tractsranged from 2 to 3. Patient clinical characteristics and demographic information were used for propensity score matching (PSM). Both groups' perioperative outcomes, procedure numbers, and efficacy quotient (EQ) were evaluated. As a more objective indicator for stone removal, EQ was calculated by SFR, retreatment rate, and auxiliary procedure rate.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe retreatment rate of the SM group was higher than the MM group (45.2% vs 21.4%, \u003cem\u003eP\u003c/em\u003e=0.031). No statistical difference between the two groups in complication rate. The initial SFR of the MM group was significantly higher than that of the SM group in a subgroup with a cumulative stone diameter (CSD) range of 40-70 mm (58.8%vs15.4%, \u003cem\u003eP\u003c/em\u003e=0.026). The MM group had a significantly lower retreatment rate than SM (23.5% vs 69.2%, \u003cem\u003eP\u003c/em\u003e=0.025), showinga higher EQ (56.5% vs 34.8%) and fewer procedures (1.35±0.49 vs 1.77±0.44, \u003cem\u003eP\u003c/em\u003e=0.023).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eIn the CSD 40-70mm subgroups,MM proved better EQ with an acceptable complication rate and fewer procedures. When the CSD ranges from 40-70mm, MM can be used as a preferred procedure for renal stones in a solitary kidney.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial registration:\u003c/strong\u003eThis study was retrospectively registered and approved by the Ethics Committee of the First Affilated Hospital of Guangzhou Medical University(2020 No.K-41)\u003c/p\u003e","manuscriptTitle":"Single-versus multi-tract mini percutaneous nephrolithotomy for renal stones in a solitary kidney: a propensity-matched study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-03-22 05:05:54","doi":"10.21203/rs.3.rs-2663590/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"47e5a445-6671-44c8-9fe1-d86f1d2c9546","owner":[],"postedDate":"March 22nd, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2023-04-15T07:44:23+00:00","versionOfRecord":[],"versionCreatedAt":"2023-03-22 05:05:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-2663590","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2663590","identity":"rs-2663590","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}