Retroperitoneal vs. Transperitoneal Laparoscopic Pyelolithotomy; a single surgeon’s experience

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Methods: A total of 104 consecutive laparoscopic pyelolithotomy surgeries performed by a single surgeon on patients with staghorn or renal pelvic calculi larger than 20 mm were evaluated. Intraoperative and postoperative clinical parameters from two groups, transperitoneal (TLPL) (N=55) and retroperitoneal (RLPL) (N=49), were compared. The surgeon performed TLPL for the first five years and then switched to the RLPL approach for the next five years. Results: There were no significant differences in general demographic variables and stone size (26.55 vs 24.73 mm, P = 0.8). Operation time and change in serum creatinine levels did not significantly differ between the two approaches. However, patients who underwent TLPL had longer hospital stays than RLPL (3.23±1.21 vs 2.36±1.10 days, P=0.0001). Prolonged hospitalization of more than three days occurred in 30.9% of the TLPL group compared to 8.2% for the RLPL group (P=0.004). Additionally, TLPL was associated with a greater drop in hemoglobin levels (1.53 ±1.04 vs 1.17±0.68, P=0.04), higher rates of postoperative fever (12.7% vs 0.0%, P=0.01), and more major complications (Clavien classification grade >3) (10.9% in TLPL vs 2% in RLPL, P=0.07). Conclusions: The retroperitoneal approach in pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups. kidney stone laparoscopy transperitoneal retroperitoneal staghorn Figures Figure 1 Figure 2 Introduction Nephrolithiasis, also known as kidney stone disease, is a common condition affecting a significant portion of the population. In the United States, about 12% of men and 7% of women experience kidney stones at some point [ 1 ]. Over the past three decades, there have been significant advancements in urologic surgery, leading to various minimally invasive surgical options for managing nephrolithiasis. These options include extracorporeal shock wave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), robotic pyelolithotomy [ 2 ], robotic anatrophic nephrolithotomy, and laparoscopic pyelolithotomy (LPL) [ 3 – 4 ]. The success of kidney stone clearance depends on factors such as stone volume, location, composition, anatomy of the collecting system, and the complexity of stone distribution [ 5 – 6 ]. With the progress of minimally invasive endoscopic procedures, today most urinary stones can be treated using these methods. Progresses in ultrasound access decreased radiation hazards significantly [ 7 – 9 ]. However, in the case of large and complex stones, several endoscopic procedures are required to clear the stones, which may not be cost-effective compared to a one-session procedure such as laparoscopy. In cases such as large and isolated pelvic stones, laparoscopic surgery consolidates its position as a powerful alternative with high success and low complications compared to PCNL [ 10 – 11 ]. Many studies have compared the effectiveness and complications of laparoscopic pyelolithotomy and PCNL for pelvic stones larger than 2 cm. In a meta-analysis, Wang et al concluded that laparoscopic pyelolithotomy had a significantly higher stone-free rate than PCNL. In addition, the rate of hemoglobin drops and postoperative fever was lower in the laparoscopy group [ 12 ] Rui and his colleagues also conducted a meta-analysis in this field, and in their study, the rate of stone removal in laparoscopy was higher than PCNL [ 13 ]. In addition, LPL is linked to a reduced rate of kidney stone recurrence in the future [ 14 ]. Moreover, laparoscopic vision may provide data about the possible undiagnosed anatomical factors causing stone lodgment [ 15 ]. From the sum of the meta-analyses and despite the heterogeneity that exists regarding the operation time, length of hospitalization, and the amount of bleeding, it can be claimed with a high level of evidence that the rate of stone removal in laparoscopic pyelolithotomy for single and large pelvic stones is higher than PCNL. Two approaches have been developed for LP: transperitoneal (TLPL) and retroperitoneal (RLPL). However, RLPL has a steeper learning curve due to limited working space. RLPL allows direct access to the renal pelvis and follows open surgical principles without the need to manipulate the intestine, thus reducing intestinal damage and ileus after surgery. Additionally, RLPL can lead to faster recovery of bowel function if urine leakage occurs post-surgery. Despite these advantages, many surgeons are more familiar with the transperitoneal approach due to the larger working space and better visibility of anatomical landmarks. Furthermore, transperitoneal laparoscopy is easier for beginners [ 16 ]. The choice between the TLPL or RLPL approach remains a topic of debate and there is only one study in this field including 47 patients [ 17 ]. To address the controversy surrounding the choice of approach, a study was conducted to compare the outcomes of TLPL and RLPL when performed by a single surgeon. Method The population of this research is all 104 men and women with pelvic stones who underwent laparoscopic pyelolithotomy in the referral urology department of Shahid Bahonar Teaching Hospital and Mehrgan Hospital in Kerman for 10 years (2013–2023). All procedures were accomplished by a single surgeon (the first author). The surgeon previously trained in TLPL and performed TLPL in the first 55 cases. Afterward, he completed a retroperitoneal educational course and switched to the retroperitoneal approach for the last 49 cases. This study included people of any age with staghorn stones bigger than 2 cm located in the renal pelvis or stones that failed with SWL, and willingness to LPL procedure after informed consent. Exclusion criteria were uncorrectable coagulation disorder, any contraindication for laparoscopy, and unwillingness for LPL procedure. Patients with stones located in calyces solely or those with multiple nonconnected calyceal stones which were not likely to be removed through the pyelotomy incision were excluded. Positive urine cultures were treated and enrolled after obtaining negative cultures. Surgical method Patients were operated on under general anesthesia and a Foley catheter was inserted. Then, the patient was placed in the lateral decubitus position with the table maximally flexed. A cushion was placed under the flank only for the retroperitoneal approach. In the retroperitoneal method, the retroperitoneal space was accessed through an incision below the 12th rib and then dissected by a handmade balloon using the index finger of the surgical glove filled with 300–500 ml room air. The two 5mm working trocars were placed under the guide of the index finger medial to the first incision anterior to the midaxillary line. A 10 mm trocar was placed in the first incision for the lens. The retroperitoneal space was insufflated with a constant pressure of 12 mm Hg and was controlled by capnometry. A 30° telescope was inserted through the port. A hemostatic forceps was used to cut the Gerota fascia. Then the pelvis was located and the rest of the surgery was done similarly to the transperitoneal group (Fig. 1 ). For the transperitoneal approach, the first 10 mm lens trocar was placed in the umbilical region or lateral to the rectus muscle. The pneumoperitoneum was created with a constant pressure of 12 mm Hg and monitored by capnometry. One 5 mm working trocar was placed between the lens trocar and the iliac crest and another trocar in the subcostal region. Toldt's line was opened and the colon was reflected medially after dissection. After exposing the upper part of the ureter and the pelvis, a transverse incision was made on the renal pelvis avoiding the junction of the ureter and the pelvis. Then, the stone was removed from the pelvis using Babcock forceps, and placed in an endobag to be removed at the end of the procedure. If preoperative data showed small calyceal stones, they were extracted by direct vision of the laparoscopic lens and irrigation using the laparoscopic suction-irrigation set. In complex cases, a nephroscope was inserted into the trocar, and the stone was removed using grasping forceps through the scope and then placed in the endobag. A double-J ureteral stent was inserted antegrade, the pelvis incision was repaired by 4 − 0 Vicryl or PDS separate sutures, and a flap of Gerota fat was wrapped on the incision. In the case of staghorn, the lens trocar incision was extended to allow specimen removal. A drain was inserted and the skin was repaired at trocar sites (Fig. 2 ) Follow up Complications were recorded during the operation and hospitalization. All patients were scheduled for an office visit one week after discharge and then one, three, and six months postoperatively. Complications were reported based on Clavien Dindo's Classification for surgical complications. Major complications were defined as grade 3 or more from the Clavien Dindo grading system. Stone-free status was evaluated using CT-Scan one month after the operation. Patients were followed three and six months after the operation using ultrasound for possible hydronephrosis. Ethics: This study complies with the Declaration of Helsinki and was performed according to the ethics committee approval of the KMU University with the code of IR.KMU.AH.REC.1402.198. Statistical analysis: Data analysis was performed using SPSS software (Statistical Package for the Social Sciences, v16.0; SPSS Inc., Chicago, IL, USA). Student’s t-test and Chi-square test were used. A P-value of < 0.05 was considered as statistically significant. Results Of 104 patients included, 55 were performed via the transperitoneal approach (TLPL) and 49 procedures via the retroperitoneal approach (RLPL). There were no significant differences in general demographic variables, between the two groups, concerning patient age, mean stone size, or BMI (Table 1 ). Five patients in the TLPL group and three in the RLPL group previously underwent PCNL or open stone surgery (P = 0.57). LPL was successfully performed in all 104 patients with 1 open conversion in the TLPL group (due to very dense adhesions) but there was no conversion to open in the RLPL group (P = 0.3). Table 1 Demographics and preoperative characteristics of the patient compared between the two study groups Approach RLPL TLPL Count Column N % Mean Standard Deviation Count Column N % Mean Standard Deviation P-value Gender male 32 65.3% 36 65.5% 0.98 female 17 34.7% 19 34.5% Age (year) 48.82 14.97 15.37 0.58 BMI kg/m2 25.27 4.11 23.81 3.44 0.06 Weight Status Normal 26 53.1% 37 67.3% 0.14 Overweight 15 30.6% 15 27.3% Obese 8 16.3% 3 5.5% Stone Size (mm) 24.73 7.60 26.55 6.44 0.19 Laterality Left 29 59.2% 23 41.8% 0.07 Right 20 40.8% 32 58.2% Previous Intervention None 41 83.7% 36 65.5% 0.12 Open 1 2.0% 2 3.6% TUL 0 0.0% 6 10.9% SWL 5 10.2% 8 14.5% PCNL 2 4.1% 3 5.5% Previous PCNL or Open stone surgery 3 6.1% 5 9.1% 0.32 Operative time There was no significant difference in Operation Time between the two groups (Table 2 ). We defined prolonged operative time as more than 180 minutes and found that 27.3% in the TLPL group and 14.3% in the RLPL group had prolonged operative time (P = 0.1). Linear regression shows no significant impact of approach, previous surgery, or laterality on operative time, but indicates an effect of stone size (P = 0.01). Table 2 Perioperative patient details of the two study groups and mean operating time in minutes Approach N Mean Std. Deviation P-value Operation Time (minutes) RLPL 49 132.65 36.71 0.29 TLPL 55 139.81 31.82 Hospitalization Time (Days) RLPL 49 2.36 1.21 0.0001 TLPL 55 3.23 1.10 Cr change (mg/dl) RLPL 49 -0.0043 0.22 0.09 TLPL 55 0.07 0.25 Hb Drop RLPL 49 1.17 0.68 0.04 TLPL 55 1.53 1.04 Hospital stays Patients who underwent TLPL stayed in the hospital significantly longer (3.23 ± 1.21 vs 2.36 ± 1.10, P = 0.0001). Prolonged hospitalization, defined as more than three days of admission, occurred in 30.9% of the TLPL group compared to 8.2% for the RLPL group (P = 0.004). Stone Free Rate Stone Free Rate (SFR) at 1 month was 90.9% for the TLPL group and 87.8% for the RLPL group (p = 0.6) (Table 3 ). Table 3 Prolonged operation time, hospitalization, and stone free status compared between two groups Approach RLPL TLPL Count Column N % Count Column N % P-value Prolonged Operation Time More than 3 Hours 27 14.3% 25 27.3% 0.1 Prolonged Hospitalization More Than 3 Days 4 8.2% 17 30.9% 0.004 Stone Free Status (at 1 month) Percent 43 87.8% 50 90.9% 0.6 Complications In the RLPL group, one patient experienced a severe urine leak. He had a history of ESWL with difficulty repairing the pelvis during RLPL. After waiting for a week, the leakage did not stop. Therefore, we inserted a nephrostomy catheter, and the day after urine stopped leaking. The nephrostomy tube was clamped one week later and removed. Another patient in the TLPL group experienced heavy leakage of urine. She similarly underwent local nephrostomy placement and leakage stopped. In the TLPL approach, two patients required a blood transfusion, five patients had a fever, two patients had cardiac complications (acute coronary syndrome and unstable angina), and two had UTIs requiring a change of antibiotics. Moreover, the TLPL approach was associated with more hemoglobin drop (1.53 ± 1.04 vs 1.17 ± 0.68, P = 0.04). One patient from the TLPL group died one week after the operation. This patient showed dizziness on the second postoperative day. The abdominopelvic CT scan showed no residual stone or collection but a posterior fossa mass with hydrocephaly was observed in the brain imaging. This patient was transferred to the neurosurgery department and underwent an emergent neurosurgical procedure for the treatment of hydrocephaly. The consciousness increased after that but unfortunately, he died suddenly after one week in the neurosurgery department. The death was not a complication of TLPL itself but secondary to the undiagnosed brain tumor. Nevertheless, the rate of major complications was not significantly different in the study groups. Postoperative major complications (grade 3 or more) occurred in six (10.2%) of patients in the TLPL group and one (2%) patient in the RLPL group. None of the patients showed hydronephrosis and stenosis during the follow-up (P = 0.07) (Table 4 ). Table 4 Complications reported based on the Clavien grading system compared between the two study groups Approach RLPL TLPL Count Column N % Count Column N % P-value Fever 0 0.0% 7 12.7% 0.01 Complications grade None 35 71.4% 39 70.9% 0.07 I 13 26.5% 6 10.9% II 0 0.0% 4 7.3% IIIa 1 2.0% 1 1.8% IIIb 0 0.0% 1 1.8% IV 0 0.0% 3 5.5% V 0 0.0% 1 1.8% Major Complication Grade III or more 1 2.0% 6 10.9% 0.07 Discussion In this study, the results of laparoscopic pyelolithotomy using transperitoneal or retroperitoneal approaches were compared by a single surgeon. The success rates were similar between the two groups, but the retroperitoneal approach led to faster recovery and lower rates of postoperative fever and intraoperative hemorrhage. This study, involving 104 patients, suggests that the retroperitoneal approach may be a better option for treating patients with large kidney stones. Another study by Al-Hunayan et al compared transperitoneal and retroperitoneal laparoscopic pyelolithotomy in 48 patients with kidney stones larger than 3 cm and found that patients in the TLPL group had longer hospital stays than RLPL. They reported no significant difference in blood loss between the two groups, but the operative time favored the retroperitoneal group. It should be remembered that the TLPL group in their study had a higher BMI [ 17 ]. In contrast, our study showed no significant difference in the operative time between the two groups. The transperitoneal approach aids in finding the pelvis faster due to anatomical landmarks and provides a wider working space for easier suturing. Conversely, in the retroperitoneal approach, there is no need for bowel reflection, especially for the left-sided kidney, which may contribute to decreased operative time. Nevertheless, limited working space in the retroperitoneal approach causes difficulties in intracorporeal suturing and stent placement. In the Al-Hunayan series, 33% of the pyelotomy incisions were left unclosed in the retroperitoneal approach compared with 18% in the transperitoneal approach [ 17 ]. Similarly, in Abat's report for ureterolithotomy, JJ stent was not placed in 32% of patients in the retroperitoneal group which may have caused prolonged leakage in this group [ 16 ]. Large working space in the TLPL may work as a double-edged sword when the stone migrates to the peritoneal cavity. This may prolong the operative time or cause collection between bowel loops if unnoticed. Al-Hunayan reported a case of peritonitis due to an unrecognized migrated stone into the peritoneal cavity during TLPL. They performed open laparotomy and exploration to remove the infected collection. Similarly, infected urine may affect the recovery of bowel function after TLPL. In the reported series, the postoperative ileus is higher after TLPL [ 17 ]. Even non-infected urine, including tiny stone particles, may contain bacterial products that could be linked to a higher rate of postoperative fever in patients undergoing TLPL in our study [ 12 ]. This complication would be eliminated using RLPL. In a meta-analysis of randomized controlled trials comparing percutaneous nephrolithotomy (PCNL) with laparoscopic pyelolithotomy (LPL), both groups had a similar average hospital admission period of 4.8 and 4.5 days, respectively [ 11 ]. However, our study showed that patients who underwent RLPL had a faster discharge of 2.3 days on average. Specifically, 92% of patients in the RLPL group were hospitalized for less than three days, including the operative day, whereas this rate was 70% for the TLPL group. This suggests that RLPL is associated with faster recovery and can be a viable alternative to the trend of discharging patients more quickly after the PCNL procedure [ 19 ]. The learning curve for laparoscopic pyelolithotomy is steep, especially when it comes to challenges such as removing the staghorn stone from the pyelotomy incision, intracorporeal suturing, and placing a JJ stent. Since this procedure is typically performed by surgeons experienced in advanced laparoscopic procedures, there is limited data on the learning curve for laparoscopic pyelolithotomy. In contrast, it has been reported that an inexperienced surgeon would need to perform around 60 cases of percutaneous nephrolithotomy (PCNL) to achieve surgical competence [ 20 ]. The transperitoneal approach is considered easier due to the wider working space, making suturing easier and providing more familiar anatomical landmarks. This is particularly important in academic settings where the procedure is being taught to less experienced surgeons. A study comparing the results of retroperitoneal versus transperitoneal laparoscopic ureterolithotomy found that the mean hospital stay and urinary leakage were higher in the retroperitoneal approach while operating time was longer in the transperitoneal approach. However, this study had limitations, such as significant differences in stone size favoring the retroperitoneal group, and comparing two different surgeons performing each approach [ 16 ]. A key advantage of our study is that all operations were performed by a single surgeon, ensuring consistency in patient care. However, the surgeon had prior experience with the transperitoneal approach before transitioning to the retroperitoneal approach, which may have influenced the results. Nonetheless, the operative time was similar between the two approaches. Despite these findings, there is a need for a randomized clinical trial to be conducted in a center experienced in both approaches to provide more conclusive evidence. Conclusion The retroperitoneal approach in pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups. Declarations The authors declare that they have no conflict of interest. Author Contribution Hamid pakmanesh wrote the main manuscript text and Ali Salari prepared figures and tables. Data Availability Data is provided within the manuscript or supplementary information files References Pearle MS, Calhoun EA, Curhan GC et al (2005) Urologic diseases in America project: urolithiasis. 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Biomed Res Int 2019:3428123. 10.1155/2019/3428123 Pakmanesh H, Mirzaei M, Mohammad_Salehi S et al (2020) Different Aspect of Transperitoneal Laparoscopic Pyelolithotomy for Management of Pelvic Stones Larger than 20 mm: a Cuasi-Experimental Study in Male Patients. Men's Health J 4:e13–e13 Mao T, Wei N, Yu J et al (2021) Efficacy and safety of laparoscopic pyelolithotomy versus percutaneous nephrolithotomy for treatment of large renal stones: a meta-analysis. J Int Med Res 49(1):300060520983136. 10.1177/0300060520983136 [published Online First: 2021/01/22] Wang X, Li S, Liu T et al (2013) Laparoscopic pyelolithotomy compared to percutaneous nephrolithotomy as surgical management for large renal pelvic calculi: a meta-analysis. J Urol 190(3):888–893 Rui X, Hu H, Yu Y et al (2016) Comparison of safety and efficacy of laparoscopic pyelolithotomy versus percutaneous nephrolithotomy in patients with large renal pelvic stones: a meta-analysis. J Investig Med 64(6):1134–1142 Pakmanesh H, MohammadSalehi S, Mirzaei M et al (2024) Medium-Term Stone Recurrence after zero-fragment transperitoneal Laparoscopic Pyelolithotomy Compared with Percutaneous Nephrolithotomy for Large Single Renal Pelvis Stones. Urol J 21(1):35–39. 10.22037/uj.v20i.7676 Radfar MH, Valipour R, Narouie B et al (2018) Role of the gonadal vessels on the stone lodgment in the proximal ureter: Direct observation during laparoscopic ureterolithotomy. Arch Ital Urol Androl 90(3):163–165. 10.4081/aiua.2018.3.163 Abat D, Altunkol A, Kuyucu F et al (2016) After a urological laparoscopic training programme, which laparoscopic method is safer and more feasible in the management of proximal ureteral stones: Transperitoneal or retroperitoneal? JPMA J Pakistan Med Association 66(8):971–976 [published Online First: 2016/08/16] Al-Hunayan A, Abdulhalim H, El‐Bakry E et al (2009) Laparoscopic pyelolithotomy: is the retroperitoneal route a better approach? Int J Urol 16(2):181–186 Ziaee SA, Kazemi B, Moghaddam SM et al (2008) A study of febrile versus afebrile patients after percutaneous nephrolithotomy regarding bacterial etiologic factors through blood and urine cultures and 16S rRNA detection in serum. J Endourol 22(12):2717–2721. 10.1089/end.2007.0417 Basiri A, Arab D, Pakmanesh H et al (2020) An Overnight Stay Versus three Days Admission after Uncomplicated Percutaneous Nephrolithotomy: A Randomized Clinical Trial. Urol J 17(4):352–357. 10.22037/uj.v0i0.5314 Tanriverdi O, Boylu U, Kendirci M et al (2007) The learning curve in the training of percutaneous nephrolithotomy. Eur Urol 52(1):206–211. 10.1016/j.eururo.2007.01.001 [published Online First: 2007/01/19] Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 03 Oct, 2024 Read the published version in World Journal of Urology → Version 1 posted Editorial decision: Revision requested 07 Aug, 2024 Reviews received at journal 31 Jul, 2024 Reviewers agreed at journal 26 Jul, 2024 Reviews received at journal 22 Jul, 2024 Reviewers agreed at journal 30 Jun, 2024 Reviewers invited by journal 28 Jun, 2024 Editor assigned by journal 28 Jun, 2024 Submission checks completed at journal 27 Jun, 2024 First submitted to journal 23 Jun, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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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-4624108","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":330041539,"identity":"dfa33a2f-e74e-476f-a0b2-19b7976197fc","order_by":0,"name":"Hamid Pakmanesh","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3klEQVRIiWNgGAWjYBACgwMMDIwNYCYP4wMGhgOkaWE2IFkLmwSRWngPfpyZY5fHz3/2WDVPzR05fgbmh49u4NFif4AvWXLjtuRiyRl5abd5jj0zlmxgMzbOwWsLj4Hkw23MiRtu8Jjd5mE7nLjhAA+bNAEtxj8fbqtP3H/+jFkxzz/itJgBHQZUyZBjxszbRpQWvjTLmduOJ864kWMsObfvsLFkM0G/8B6+2butOrG//4zhhzffDsvxszc/fIxPC4P8GwSbiQdEMuNTDgY8CCbjD4KqR8EoGAWjYCQCAAUkU1C03ppxAAAAAElFTkSuQmCC","orcid":"","institution":"Kerman University of Medical Sciences","correspondingAuthor":true,"prefix":"","firstName":"Hamid","middleName":"","lastName":"Pakmanesh","suffix":""},{"id":330041540,"identity":"c2383b76-4608-461f-b8a7-434ed3b1457a","order_by":1,"name":"Ali Salari","email":"","orcid":"","institution":"Kerman University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Ali","middleName":"","lastName":"Salari","suffix":""}],"badges":[],"createdAt":"2024-06-23 06:53:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4624108/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4624108/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00345-024-05265-x","type":"published","date":"2024-10-03T15:57:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":60911599,"identity":"73bd51f2-497f-4b05-bd52-14d307570862","added_by":"auto","created_at":"2024-07-23 12:58:14","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":5237909,"visible":true,"origin":"","legend":"\u003cp\u003eretroperitoneal Approach: A: CT scan shows a large staghorn stone. B: Patient positioned for RLPL. C: Placement of ports D: corrugated drain D: Large staghorn stone removed E: Patient wound after recovery\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4624108/v1/0e628ccef0e825bf4457675c.png"},{"id":60912837,"identity":"709c5907-1ffe-4308-bb32-8dbd18400895","added_by":"auto","created_at":"2024-07-23 13:06:14","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1064380,"visible":true,"origin":"","legend":"\u003cp\u003eTransperitoneal Approach: (A) Preoperative CT scan demonstrates a large staghorn calculus. (B) A laparoscopic view of the left kidney pelvis (C) Antegrade JJ stent placement (D) Pelvis repair (E) The large staghorn stone\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4624108/v1/196f50d833b00a9dc4e9d67e.png"},{"id":66096731,"identity":"56ab39f8-2659-408f-8e4f-985787028ba3","added_by":"auto","created_at":"2024-10-07 16:08:13","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":9232690,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4624108/v1/a9f60a58-29d8-4fc9-9d54-c8b2a4341398.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Retroperitoneal vs. Transperitoneal Laparoscopic Pyelolithotomy; a single surgeon’s experience","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNephrolithiasis, also known as kidney stone disease, is a common condition affecting a significant portion of the population. In the United States, about 12% of men and 7% of women experience kidney stones at some point [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Over the past three decades, there have been significant advancements in urologic surgery, leading to various minimally invasive surgical options for managing nephrolithiasis. These options include extracorporeal shock wave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), robotic pyelolithotomy [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], robotic anatrophic nephrolithotomy, and laparoscopic pyelolithotomy (LPL) [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The success of kidney stone clearance depends on factors such as stone volume, location, composition, anatomy of the collecting system, and the complexity of stone distribution [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. With the progress of minimally invasive endoscopic procedures, today most urinary stones can be treated using these methods. Progresses in ultrasound access decreased radiation hazards significantly [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, in the case of large and complex stones, several endoscopic procedures are required to clear the stones, which may not be cost-effective compared to a one-session procedure such as laparoscopy. In cases such as large and isolated pelvic stones, laparoscopic surgery consolidates its position as a powerful alternative with high success and low complications compared to PCNL [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Many studies have compared the effectiveness and complications of laparoscopic pyelolithotomy and PCNL for pelvic stones larger than 2 cm. In a meta-analysis, Wang et al concluded that laparoscopic pyelolithotomy had a significantly higher stone-free rate than PCNL. In addition, the rate of hemoglobin drops and postoperative fever was lower in the laparoscopy group [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] Rui and his colleagues also conducted a meta-analysis in this field, and in their study, the rate of stone removal in laparoscopy was higher than PCNL [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In addition, LPL is linked to a reduced rate of kidney stone recurrence in the future [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Moreover, laparoscopic vision may provide data about the possible undiagnosed anatomical factors causing stone lodgment [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. From the sum of the meta-analyses and despite the heterogeneity that exists regarding the operation time, length of hospitalization, and the amount of bleeding, it can be claimed with a high level of evidence that the rate of stone removal in laparoscopic pyelolithotomy for single and large pelvic stones is higher than PCNL.\u003c/p\u003e \u003cp\u003eTwo approaches have been developed for LP: transperitoneal (TLPL) and retroperitoneal (RLPL). However, RLPL has a steeper learning curve due to limited working space. RLPL allows direct access to the renal pelvis and follows open surgical principles without the need to manipulate the intestine, thus reducing intestinal damage and ileus after surgery. Additionally, RLPL can lead to faster recovery of bowel function if urine leakage occurs post-surgery. Despite these advantages, many surgeons are more familiar with the transperitoneal approach due to the larger working space and better visibility of anatomical landmarks. Furthermore, transperitoneal laparoscopy is easier for beginners [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The choice between the TLPL or RLPL approach remains a topic of debate and there is only one study in this field including 47 patients [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo address the controversy surrounding the choice of approach, a study was conducted to compare the outcomes of TLPL and RLPL when performed by a single surgeon.\u003c/p\u003e"},{"header":"Method","content":"\u003cp\u003eThe population of this research is all 104 men and women with pelvic stones who underwent laparoscopic pyelolithotomy in the referral urology department of Shahid Bahonar Teaching Hospital and Mehrgan Hospital in Kerman for 10 years (2013\u0026ndash;2023). All procedures were accomplished by a single surgeon (the first author). The surgeon previously trained in TLPL and performed TLPL in the first 55 cases. Afterward, he completed a retroperitoneal educational course and switched to the retroperitoneal approach for the last 49 cases.\u003c/p\u003e \u003cp\u003eThis study included people of any age with staghorn stones bigger than 2 cm located in the renal pelvis or stones that failed with SWL, and willingness to LPL procedure after informed consent. Exclusion criteria were uncorrectable coagulation disorder, any contraindication for laparoscopy, and unwillingness for LPL procedure. Patients with stones located in calyces solely or those with multiple nonconnected calyceal stones which were not likely to be removed through the pyelotomy incision were excluded. Positive urine cultures were treated and enrolled after obtaining negative cultures.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSurgical method\u003c/h2\u003e \u003cp\u003ePatients were operated on under general anesthesia and a Foley catheter was inserted. Then, the patient was placed in the lateral decubitus position with the table maximally flexed. A cushion was placed under the flank only for the retroperitoneal approach.\u003c/p\u003e \u003cp\u003eIn the retroperitoneal method, the retroperitoneal space was accessed through an incision below the 12th rib and then dissected by a handmade balloon using the index finger of the surgical glove filled with 300\u0026ndash;500 ml room air. The two 5mm working trocars were placed under the guide of the index finger medial to the first incision anterior to the midaxillary line. A 10 mm trocar was placed in the first incision for the lens. The retroperitoneal space was insufflated with a constant pressure of 12 mm Hg and was controlled by capnometry. A 30\u0026deg; telescope was inserted through the port. A hemostatic forceps was used to cut the Gerota fascia. Then the pelvis was located and the rest of the surgery was done similarly to the transperitoneal group (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFor the transperitoneal approach, the first 10 mm lens trocar was placed in the umbilical region or lateral to the rectus muscle. The pneumoperitoneum was created with a constant pressure of 12 mm Hg and monitored by capnometry. One 5 mm working trocar was placed between the lens trocar and the iliac crest and another trocar in the subcostal region. Toldt's line was opened and the colon was reflected medially after dissection. After exposing the upper part of the ureter and the pelvis, a transverse incision was made on the renal pelvis avoiding the junction of the ureter and the pelvis. Then, the stone was removed from the pelvis using Babcock forceps, and placed in an endobag to be removed at the end of the procedure. If preoperative data showed small calyceal stones, they were extracted by direct vision of the laparoscopic lens and irrigation using the laparoscopic suction-irrigation set. In complex cases, a nephroscope was inserted into the trocar, and the stone was removed using grasping forceps through the scope and then placed in the endobag. A double-J ureteral stent was inserted antegrade, the pelvis incision was repaired by 4\u0026thinsp;\u0026minus;\u0026thinsp;0 Vicryl or PDS separate sutures, and a flap of Gerota fat was wrapped on the incision. In the case of staghorn, the lens trocar incision was extended to allow specimen removal. A drain was inserted and the skin was repaired at trocar sites (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFollow up\u003c/p\u003e \u003cp\u003eComplications were recorded during the operation and hospitalization. All patients were scheduled for an office visit one week after discharge and then one, three, and six months postoperatively. Complications were reported based on Clavien Dindo's Classification for surgical complications. Major complications were defined as grade 3 or more from the Clavien Dindo grading system. Stone-free status was evaluated using CT-Scan one month after the operation. Patients were followed three and six months after the operation using ultrasound for possible hydronephrosis.\u003c/p\u003e \u003cp\u003eEthics:\u003c/p\u003e \u003cp\u003e This study complies with the Declaration of Helsinki and was performed according to the ethics committee approval of the KMU University with the code of IR.KMU.AH.REC.1402.198.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis:\u003c/h2\u003e \u003cp\u003eData analysis was performed using SPSS software (Statistical Package for the Social Sciences, v16.0; SPSS Inc., Chicago, IL, USA). Student\u0026rsquo;s t-test and Chi-square test were used. A P-value of \u0026lt;\u0026thinsp;0.05 was considered as statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eOf 104 patients included, 55 were performed via the transperitoneal approach (TLPL) and 49 procedures via the retroperitoneal approach (RLPL). There were no significant differences in general demographic variables, between the two groups, concerning patient age, mean stone size, or BMI (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). Five patients in the TLPL group and three in the RLPL group previously underwent PCNL or open stone surgery (P\u0026thinsp;=\u0026thinsp;0.57). LPL was successfully performed in all 104 patients with 1 open conversion in the TLPL group (due to very dense adhesions) but there was no conversion to open in the RLPL group (P\u0026thinsp;=\u0026thinsp;0.3).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDemographics and preoperative characteristics of the patient compared between the two study groups\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth colspan=\"2\" rowspan=\"3\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth colspan=\"5\" align=\"left\"\u003e\n \u003cp\u003eApproach\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStandard Deviation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStandard Deviation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e65.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e65.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003efemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eAge (year)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e48.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eBMI kg/m2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e23.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eWeight Status\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNormal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd rowspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOverweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eStone Size (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e26.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eLaterality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeft\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e59.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e40.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e58.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" align=\"left\"\u003e\n \u003cp\u003ePrevious Intervention\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e83.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e65.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd rowspan=\"5\" align=\"left\"\u003e\n \u003cp\u003e0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOpen\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTUL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSWL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePCNL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003ePrevious PCNL or Open stone surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.32\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\u003eOperative time\u003c/p\u003e\n\u003cp\u003eThere was no significant difference in Operation Time between the two groups (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). We defined prolonged operative time as more than 180 minutes and found that 27.3% in the TLPL group and 14.3% in the RLPL group had prolonged operative time (P\u0026thinsp;=\u0026thinsp;0.1). Linear regression shows no significant impact of approach, previous surgery, or laterality on operative time, but indicates an effect of stone size (P\u0026thinsp;=\u0026thinsp;0.01).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab2\" style=\"width: 453px;\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePerioperative patient details of the two study groups and mean operating time in minutes\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth style=\"width: 152px;\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eApproach\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003eStd. Deviation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 46.9954px;\" align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 152px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eOperation Time (minutes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e132.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e36.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46.9954px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e139.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e31.82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 152px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eHospitalization Time (Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e2.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e1.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46.9954px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e3.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e1.10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 152px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eCr change (mg/dl)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e-0.0043\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46.9954px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 152px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eHb Drop\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e1.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46.9954px;\" rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 58px;\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\" align=\"left\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\" align=\"left\"\u003e\n \u003cp\u003e1.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\" align=\"left\"\u003e\n \u003cp\u003e1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n \u003ch2\u003eHospital stays\u003c/h2\u003e\n \u003cp\u003ePatients who underwent TLPL stayed in the hospital significantly longer (3.23\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21 vs 2.36\u0026thinsp;\u0026plusmn;\u0026thinsp;1.10, P\u0026thinsp;=\u0026thinsp;0.0001). Prolonged hospitalization, defined as more than three days of admission, occurred in 30.9% of the TLPL group compared to 8.2% for the RLPL group (P\u0026thinsp;=\u0026thinsp;0.004).\u003c/p\u003e\n \u003cp\u003eStone Free Rate\u003c/p\u003e\n \u003cp\u003eStone Free Rate (SFR) at 1 month was 90.9% for the TLPL group and 87.8% for the RLPL group (p\u0026thinsp;=\u0026thinsp;0.6) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eProlonged operation time, hospitalization, and stone free status compared between two groups\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth colspan=\"2\" rowspan=\"3\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth colspan=\"4\" align=\"left\"\u003e\n \u003cp\u003eApproach\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProlonged Operation Time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMore than 3 Hours\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProlonged Hospitalization\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMore Than 3 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eStone Free Status (at 1 month)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePercent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e87.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e90.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003eComplications\u003c/h2\u003e\n \u003cp\u003eIn the RLPL group, one patient experienced a severe urine leak. He had a history of ESWL with difficulty repairing the pelvis during RLPL. After waiting for a week, the leakage did not stop. Therefore, we inserted a nephrostomy catheter, and the day after urine stopped leaking. The nephrostomy tube was clamped one week later and removed. Another patient in the TLPL group experienced heavy leakage of urine. She similarly underwent local nephrostomy placement and leakage stopped. In the TLPL approach, two patients required a blood transfusion, five patients had a fever, two patients had cardiac complications (acute coronary syndrome and unstable angina), and two had UTIs requiring a change of antibiotics. Moreover, the TLPL approach was associated with more hemoglobin drop (1.53\u0026thinsp;\u0026plusmn;\u0026thinsp;1.04 vs 1.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68, P\u0026thinsp;=\u0026thinsp;0.04).\u003c/p\u003e\n \u003cp\u003eOne patient from the TLPL group died one week after the operation. This patient showed dizziness on the second postoperative day. The abdominopelvic CT scan showed no residual stone or collection but a posterior fossa mass with hydrocephaly was observed in the brain imaging. This patient was transferred to the neurosurgery department and underwent an emergent neurosurgical procedure for the treatment of hydrocephaly. The consciousness increased after that but unfortunately, he died suddenly after one week in the neurosurgery department. The death was not a complication of TLPL itself but secondary to the undiagnosed brain tumor. Nevertheless, the rate of major complications was not significantly different in the study groups. Postoperative major complications (grade 3 or more) occurred in six (10.2%) of patients in the TLPL group and one (2%) patient in the RLPL group. None of the patients showed hydronephrosis and stenosis during the follow-up (P\u0026thinsp;=\u0026thinsp;0.07) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab4\" style=\"width: 627px;\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComplications reported based on the Clavien grading system compared between the two study groups\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth style=\"width: 210px;\" colspan=\"2\" rowspan=\"3\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth style=\"width: 199px;\" colspan=\"4\" align=\"left\"\u003e\n \u003cp\u003eApproach\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 46px;\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth style=\"width: 113px;\" colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eRLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 36px;\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth style=\"width: 50px;\" align=\"left\"\u003e\n \u003cp\u003eTLPL\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 65.5533px;\" align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/th\u003e\n \u003cth style=\"width: 46px;\" align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 112px;\" align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eFever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e12.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\" align=\"left\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 112px;\" rowspan=\"7\" align=\"left\"\u003e\n \u003cp\u003eComplications grade\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eNone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e71.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e70.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\" rowspan=\"7\" align=\"left\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e26.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e10.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e7.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eIIIa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e2.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e1.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eIIIb\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e1.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eIV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e5.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e0.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e1.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 112px;\" align=\"left\"\u003e\n \u003cp\u003eMajor Complication\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\" align=\"left\"\u003e\n \u003cp\u003eGrade III or more\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 77px;\" align=\"left\"\u003e\n \u003cp\u003e2.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 36px;\" align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\" align=\"left\"\u003e\n \u003cp\u003e10.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\" align=\"left\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, the results of laparoscopic pyelolithotomy using transperitoneal or retroperitoneal approaches were compared by a single surgeon. The success rates were similar between the two groups, but the retroperitoneal approach led to faster recovery and lower rates of postoperative fever and intraoperative hemorrhage. This study, involving 104 patients, suggests that the retroperitoneal approach may be a better option for treating patients with large kidney stones. Another study by Al-Hunayan et al compared transperitoneal and retroperitoneal laparoscopic pyelolithotomy in 48 patients with kidney stones larger than 3 cm and found that patients in the TLPL group had longer hospital stays than RLPL. They reported no significant difference in blood loss between the two groups, but the operative time favored the retroperitoneal group. It should be remembered that the TLPL group in their study had a higher BMI [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In contrast, our study showed no significant difference in the operative time between the two groups. The transperitoneal approach aids in finding the pelvis faster due to anatomical landmarks and provides a wider working space for easier suturing. Conversely, in the retroperitoneal approach, there is no need for bowel reflection, especially for the left-sided kidney, which may contribute to decreased operative time. Nevertheless, limited working space in the retroperitoneal approach causes difficulties in intracorporeal suturing and stent placement. In the Al-Hunayan series, 33% of the pyelotomy incisions were left unclosed in the retroperitoneal approach compared with 18% in the transperitoneal approach [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Similarly, in Abat's report for ureterolithotomy, JJ stent was not placed in 32% of patients in the retroperitoneal group which may have caused prolonged leakage in this group [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Large working space in the TLPL may work as a double-edged sword when the stone migrates to the peritoneal cavity. This may prolong the operative time or cause collection between bowel loops if unnoticed. Al-Hunayan reported a case of peritonitis due to an unrecognized migrated stone into the peritoneal cavity during TLPL. They performed open laparotomy and exploration to remove the infected collection. Similarly, infected urine may affect the recovery of bowel function after TLPL. In the reported series, the postoperative ileus is higher after TLPL [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Even non-infected urine, including tiny stone particles, may contain bacterial products that could be linked to a higher rate of postoperative fever in patients undergoing TLPL in our study [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. This complication would be eliminated using RLPL.\u003c/p\u003e \u003cp\u003eIn a meta-analysis of randomized controlled trials comparing percutaneous nephrolithotomy (PCNL) with laparoscopic pyelolithotomy (LPL), both groups had a similar average hospital admission period of 4.8 and 4.5 days, respectively [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. However, our study showed that patients who underwent RLPL had a faster discharge of 2.3 days on average. Specifically, 92% of patients in the RLPL group were hospitalized for less than three days, including the operative day, whereas this rate was 70% for the TLPL group. This suggests that RLPL is associated with faster recovery and can be a viable alternative to the trend of discharging patients more quickly after the PCNL procedure [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. The learning curve for laparoscopic pyelolithotomy is steep, especially when it comes to challenges such as removing the staghorn stone from the pyelotomy incision, intracorporeal suturing, and placing a JJ stent. Since this procedure is typically performed by surgeons experienced in advanced laparoscopic procedures, there is limited data on the learning curve for laparoscopic pyelolithotomy. In contrast, it has been reported that an inexperienced surgeon would need to perform around 60 cases of percutaneous nephrolithotomy (PCNL) to achieve surgical competence [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The transperitoneal approach is considered easier due to the wider working space, making suturing easier and providing more familiar anatomical landmarks. This is particularly important in academic settings where the procedure is being taught to less experienced surgeons. A study comparing the results of retroperitoneal versus transperitoneal laparoscopic ureterolithotomy found that the mean hospital stay and urinary leakage were higher in the retroperitoneal approach while operating time was longer in the transperitoneal approach. However, this study had limitations, such as significant differences in stone size favoring the retroperitoneal group, and comparing two different surgeons performing each approach [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. A key advantage of our study is that all operations were performed by a single surgeon, ensuring consistency in patient care. However, the surgeon had prior experience with the transperitoneal approach before transitioning to the retroperitoneal approach, which may have influenced the results. Nonetheless, the operative time was similar between the two approaches. Despite these findings, there is a need for a randomized clinical trial to be conducted in a center experienced in both approaches to provide more conclusive evidence.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe retroperitoneal approach in pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eHamid pakmanesh wrote the main manuscript text and Ali Salari prepared figures and tables.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData is provided within the manuscript or supplementary information files\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003ePearle MS, Calhoun EA, Curhan GC et al (2005) Urologic diseases in America project: urolithiasis. J Urol 173:848\u0026ndash;857\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRosette Jdl, Assimos D, Desai M et al (2011) The clinical research office of the endourological society percutaneous nephrolithotomy global study: indications, complications, and outcomes in 5803 patients. J Endourol 25:11\u0026ndash;17\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAutorino R, Kaouk JH, Yakoubi R et al (2012) Urological laparoendoscopic single site surgery: multi-institutional analysis of risk factors for conversion and postoperative complications. J Urol 187:1989\u0026ndash;1994. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.juro.2012.01.062\u003c/span\u003e\u003cspan address=\"10.1016/j.juro.2012.01.062\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTurna B, Umul M, Demiryoguran S et al (2007) How do increasing stone surface area and stone configuration affect overall outcome of percutaneous nephrolithotomy? J Endourol 21:34\u0026ndash;43\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eel-Nahas AR, Eraky I, Shokeir AA et al (2012) Factors affecting stone-free rate and complications of percutaneous nephrolithotomy for treatment of staghorn stone. Urology 79:1236\u0026ndash;1241. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.urology.2012.01.026\u003c/span\u003e\u003cspan address=\"10.1016/j.urology.2012.01.026\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e[published Online First: 2012/04/03]\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNouralizadeh A, Pakmanesh H, Basiri A et al (2016) Solo Sonographically Guided PCNL under Spinal Anesthesia: Defining Predictors of Success. \u003cem\u003eScientifica (Cairo)\u003c/em\u003e 2016:5938514. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1155/2016/5938514\u003c/span\u003e\u003cspan address=\"10.1155/2016/5938514\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharifiaghdas F, Tabibi A, Nouralizadeh A et al (2015) Our Experience with Totally Ultrasonography-Guided Percutaneous Nephrolithotomy in Children. 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World J Urol 36(4):667\u0026ndash;671. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00345-018-2184-z\u003c/span\u003e\u003cspan address=\"10.1007/s00345-018-2184-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePakmanesh H, Daneshpajooh A, Mirzaei M et al (2019) Amplatz versus Balloon for Tract Dilation in Ultrasonographically Guided Percutaneous Nephrolithotomy: A Randomized Clinical Trial. \u003cem\u003eBiomed Res Int\u003c/em\u003e 2019:3428123. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1155/2019/3428123\u003c/span\u003e\u003cspan address=\"10.1155/2019/3428123\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePakmanesh H, Mirzaei M, Mohammad_Salehi S et al (2020) Different Aspect of Transperitoneal Laparoscopic Pyelolithotomy for Management of Pelvic Stones Larger than 20 mm: a Cuasi-Experimental Study in Male Patients. 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J Urol 190(3):888\u0026ndash;893\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRui X, Hu H, Yu Y et al (2016) Comparison of safety and efficacy of laparoscopic pyelolithotomy versus percutaneous nephrolithotomy in patients with large renal pelvic stones: a meta-analysis. J Investig Med 64(6):1134\u0026ndash;1142\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePakmanesh H, MohammadSalehi S, Mirzaei M et al (2024) Medium-Term Stone Recurrence after zero-fragment transperitoneal Laparoscopic Pyelolithotomy Compared with Percutaneous Nephrolithotomy for Large Single Renal Pelvis Stones. 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Int J Urol 16(2):181\u0026ndash;186\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZiaee SA, Kazemi B, Moghaddam SM et al (2008) A study of febrile versus afebrile patients after percutaneous nephrolithotomy regarding bacterial etiologic factors through blood and urine cultures and 16S rRNA detection in serum. J Endourol 22(12):2717\u0026ndash;2721. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1089/end.2007.0417\u003c/span\u003e\u003cspan address=\"10.1089/end.2007.0417\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBasiri A, Arab D, Pakmanesh H et al (2020) An Overnight Stay Versus three Days Admission after Uncomplicated Percutaneous Nephrolithotomy: A Randomized Clinical Trial. Urol J 17(4):352\u0026ndash;357. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.22037/uj.v0i0.5314\u003c/span\u003e\u003cspan address=\"10.22037/uj.v0i0.5314\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTanriverdi O, Boylu U, Kendirci M et al (2007) The learning curve in the training of percutaneous nephrolithotomy. Eur Urol 52(1):206\u0026ndash;211. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.eururo.2007.01.001\u003c/span\u003e\u003cspan address=\"10.1016/j.eururo.2007.01.001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e[published Online First: 2007/01/19]\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"kidney stone, laparoscopy, transperitoneal, retroperitoneal, staghorn","lastPublishedDoi":"10.21203/rs.3.rs-4624108/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4624108/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eObjective:\u003c/strong\u003e\u003c/em\u003e To compare the outcomes of transperitoneal and retroperitoneal laparoscopic pyelolithotomy procedures.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u003c/em\u003e A total of 104 consecutive laparoscopic pyelolithotomy surgeries performed by a single surgeon on patients with staghorn or renal pelvic calculi larger than 20 mm were evaluated. Intraoperative and postoperative clinical parameters from two groups, transperitoneal (TLPL) (N=55) and retroperitoneal (RLPL) (N=49), were compared. The surgeon performed TLPL for the first five years and then switched to the RLPL approach for the next five years.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e \u003c/strong\u003eThere were no significant differences in general demographic variables and stone size (26.55 vs 24.73 mm, P = 0.8). Operation time and change in serum creatinine levels did not significantly differ between the two approaches. However, patients who underwent TLPL had longer hospital stays than RLPL (3.23±1.21 vs 2.36±1.10 days, P=0.0001). Prolonged hospitalization of more than three days occurred in 30.9% of the TLPL group compared to 8.2% for the RLPL group (P=0.004). Additionally, TLPL was associated with a greater drop in hemoglobin levels (1.53 ±1.04 vs 1.17±0.68, P=0.04), higher rates of postoperative fever (12.7% vs 0.0%, P=0.01), and more major complications (Clavien classification grade \u0026gt;3) (10.9% in TLPL vs 2% in RLPL, P=0.07).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e\u003c/em\u003e The retroperitoneal approach in pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups.\u003c/p\u003e","manuscriptTitle":"Retroperitoneal vs. Transperitoneal Laparoscopic Pyelolithotomy; a single surgeon’s experience","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-23 12:58:09","doi":"10.21203/rs.3.rs-4624108/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-08-07T20:18:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-07-31T17:29:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"144075774572013183533761097734250329921","date":"2024-07-26T14:55:41+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-07-22T08:46:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"49776530374144957702782018965203339283","date":"2024-06-30T07:59:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-06-28T21:24:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-28T05:35:25+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-06-27T11:35:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Urology","date":"2024-06-23T06:50:43+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"3bed1ee3-4062-4530-9286-525c4b7a74d6","owner":[],"postedDate":"July 23rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-10-07T15:59:29+00:00","versionOfRecord":{"articleIdentity":"rs-4624108","link":"https://doi.org/10.1007/s00345-024-05265-x","journal":{"identity":"world-journal-of-urology","isVorOnly":false,"title":"World Journal of Urology"},"publishedOn":"2024-10-03 15:57:00","publishedOnDateReadable":"October 3rd, 2024"},"versionCreatedAt":"2024-07-23 12:58:09","video":"","vorDoi":"10.1007/s00345-024-05265-x","vorDoiUrl":"https://doi.org/10.1007/s00345-024-05265-x","workflowStages":[]},"version":"v1","identity":"rs-4624108","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4624108","identity":"rs-4624108","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}