Comparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones

Comparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research article Comparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones Tsung-Hsin Chang, Wun-Rong Lin, Wei-Kung Tsai, Pai-Kai Chiang, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-24107/v3 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Nov, 2020 Read the published version in BMC Urology → Version 3 posted 5 You are reading this latest preprint version Show more versions Abstract Background: In this study, we aimed to compare the efficacy and clinical outcomes of shock wave lithotripsy (SWL) for patients with renal stones using pure fluoroscopy (FS) or ultrasound-assisted (USa) localization with two lithotripters. Methods: We retrospectively identified 425 patients with renal calculi who underwent SWL with either a LiteMed LM-9200 ELMA lithotripter (209 cases), which combined ultrasound and fluoroscopic stone targeting or a Medispec EM-1000 lithotripter machine (216 cases), which used fluoroscopy for stone localization and tracking. The patient demographic data, stone-free rates, stone disintegration rates, retreatment rates and complication rates were analyzed. Results: The USa group had a significantly higher overall stone-free rate (43.6 vs. 28.2%, p<0.001) and stone disintegration rate (85.6 vs. 64.3%, p<0.001), as well as a significantly lower retreatment rate (14.8 vs. 35.6%, p<0.001) and complication rate (1.9 vs. 5.5%, p=0.031) compared with the FS group. This superiority remained significant in the stone size 1cm group, the stone-free rate (32.4 vs. 17.8%, p=0.028), disintegration rate (89.2 vs. 54.8%, p=0.031) and retreatment rate (21.6 vs. 53.4%, p<0.001) were still significantly better in the USa group, however there was no significant difference in the complication rate. The most common complication was post-SWL-related flank pain. Conclusion: SWL is a safe and non-invasive way of treating renal stones. this study compared two electromagnetic shock wave machines with different stone tracking systems. LiteMed LM-9200 ELMA lithotripter, which combined ultrasound and fluoroscopic stone targeting outperformed Medispec EM-1000 lithotripter, which used fluoroscopy for stone localization and tracking, with better stone-free rates and disintegration rates, as well as lower retreatment rates and complications with possible reduced radiation exposure. Urology & Nephrology Shock wave lithotripsy nephrolithiasis Kidney ultrasonography Background Extracorporeal shock wave lithotripsy (SWL) has been used as a non-invasive method of urolithiasis management since the 1980’s [1]. It has been proven to be a safe, efficient way of treating non-infected upper urinary tract stones and remains one of the most commonly used treatment modality for renal stones worldwide today. Contemporary studies have shown that the success rate of SWL for renal stones ranges from 47 to 92% [2-7]. This highly variable result is due to various crucial factors, including stone composition and size [8-11], skin to stone distance [12], lithotripter energy power [13] and frequency [14, 15], patient positioning [16], and patient tolerance and respiration [16, 17]. Less than half of the administered shockwaves may be accurately focused on the targeted calculus [18], and the excessive energy and shockwaves can cause damage to the parenchyma and adjacent organs. Chen et al. [19] demonstrated increased accuracy of stone targeting by using an electromagnetic lithotripter integrated with both ultrasound real-time tracking system and traditional fluoroscopy (LiteMed LM-9200 ELMA). Through the alternative use of ultrasound and fluoroscopy, the energy of the lithotripter may be more focused on the target stone during the whole session, thus increasing SWL efficiency. However, only a few studies have compared the efficacy of ultrasound-based lithotripters with fluoroscopy-based lithotripters. It is difficult to compare efficacy between different institutions due to variabilities in treatment protocols and operators. The current study compared the efficacy and clinical outcomes of two electromagnetic lithotripters using different stone localization methods (LiteMed LM-9200 ELMA lithotripter: combined ultrasound and fluoroscopic stone targeting; Medispec EM-1000 lithotripter: pure fluoroscopic stone targeting), in a single center with 2 hospital branches, using the same group of urologists and the same set of patients and surgical indications. The machines were operated by the same two experienced technicians, which minimizes operator and institutional related bias. The aim of the current study was to compare the efficacy and clinical outcomes of these two different stone localization modalities in the treatment of renal stones in one single medical center. Methods The present study retrospectively reviewed the medical records of patients with radio-opaque kidney stones with stone size between 0.5 to 2.0 cm who underwent SWL in a single medical center with 2 hospital branches between January 2013 and March 2019. Exclusion criteria were patients with congenital anomalies or urinary diversion, pediatric patients or patients who received SWL as a combination therapy with other treatment modalities. Patients with radiolucent stones were also excluded as plain x-rays were used as the standard follow-up modality. All patients underwent imaging and laboratory studies prior to SWL. Plain abdominal radiography of the kidneys, ureter and bladder (KUB), renal sonography, intravenous urography (IVU) and abdominal computed tomography (CT) were used to diagnose and identify the stones. The size of the stones were measured on the KUB using maximal stone diameters. Patients underwent SWL at two branches of our medical center with either a LiteMed LM-9200 ELMA lithotripter or Medispec LTD EM-1000 lithotripter, depending on their location. The distance between the two branches of our medical center were about 10 km with about a 20 minute driving time and both were located in the northern part of the city. There were no regional characteristics different between the patients of the two branches, such as water composition and eating habits. The energy source of both lithotripters was an electromagnetic shockwave source. The focal length was 145mm for EM-1000 and 125mm for LM-9200. All SWL treatments were performed on an ambulatory basis by the same group of urologists. Both machines were operated by the same two experienced technicians. The LiteMed LM-9200 ELMA lithotripter used ultrasonography and fluoroscopy for dual focusing of stone localization and tracking, while the EM1000 machine used only fluoroscopy for stone visualization, with an integrated computerized fluoroscopic X-ray (Visionspec TM ). The LiteMed LM-9200 machine has a auto-firing system, the shockwaves will only be fired when the stone is in the focal zone. The same standardized SWL protocol was used for both machines except for the stone localization method. The patient was placed in a supine position without a restraint belt. The cushion size and lubricating jelly used were the same in both branch. and the stone was located by the fluoroscopy in both group. In the USa group, ultrasound was combined use for dual stone localization before initiating the SWL session and during the treatment for real time tracking of the stone. While in the FS group, only pure fluoroscopy was used throughout the whole session. During SWL, the initial energy level was set at 14KV and could gradually increased up to 19 KV if the stones did not show adequate fragmentation under low energy settings. The shock wave rate was set at 60 shocks per minute for both lithotripters. The maximum number of shockwaves delivered in one session was 3,000. Light intravenous propofol and dormicum were used as analgesics or for sedation if the patient suffered from pain or could not tolerate lying still in the supine position throughout the SWL session. The patient’s position was adjusted throughout the SWL session for better stone visualization. If the patient’s stone is still in focal zone, the position of the patient will not be changed to avoid constant de-coupling and re-coupling. In the FS group, the position was checked and adjusted after every 600 shocks or when the patient moved. While in the USa group, positioning was adjusted based on the ultrasound tracking of the stone location throughout the SWL session. All patient received SWL sessions on an ambulatory basis, analgesics with Diclofenac or Acetaminophen were prescribed for post-operative pain control. Patients were evaluated at 4, 12 and 24 weeks after the SWL session by KUB. Stone-free status was defined as the absence of radiographic residual stones in the follow-up imaging, any residual fragments visible on KUB was considered as non-stone-free. The KUB x-ray. Stone disintegration was defined as the presence of stone destruction, fragmentation or a decrease in size in the post-session KUB compared with the pre-session KUB. Retreatment was defined as the need for further surgical intervention (repeat SWL, rigid ureteroscopic lithotripsy (URSL), retrograde intrarenal surgery (RIRS) or percutaneous nephrolithotomy (PCNL)) for symptomatic patients or patients with residual stone fragments >0.5 cm. Complications were classified according to the Clavien-Dindo classification system. All data were analyzed and compared using t-tests and chi-squared tests with IBM SPSS statistics version 25.0 software. Statistical significance was set at P<0.05. The present study, including its research protocols and data collection, were approved by the Mackay Memorial Hospital Institutional Review Board. All personal information was de-identified prior to data analysis, thus ensuring patient data confidentiality. Results Of the 425 included patients, 209 were treated with USa SWL and 216 were treated with FS SWL. The mean age of patients was 53.3±13.2 years in the USa group and 53.8±12.4 years in the FS group (p=0.538). Comparison of the two groups revealed that the FS group was significantly more male dominated (p=0.016) and there were significantly larger stones in the USa group (1.03±0.37cm vs. 0.87±0.33cm, p<0.005) (Table 1). Statistical analysis revealed better treatment outcomes in the USa group. The overall stone free rate was significantly better in the USa group compared with the FS group (USa 43.5% vs. FS 28.2%, p<0.001), and the overall stone disintegration rates were significantly higher (USa 85.6% vs. FS 64.3%, p<0.001). Significant lower retreatment (USa 14.8% vs. FS 35.6%, p<0.001) and complication rates (USa 1.9% vs. FS 5.5%, p=0.031) were noted in the USa group compared with the FS group (Table 2). Patients were further stratified by stone size ( <1cm and ≥ 1cm), and the results were similar following stratification. In the group with renal stones <1cm the USa group had a significantly higher stone free rate (USa 56.1% vs. FS 33.5%, p<0.001) and stone disintegration rate (USa 81.6% vs. FS 69.2%, p=0.031) compared with the FS group. The USa group also had a significantly lower retreatment rate (USa 7.1% vs. FS 26.5%, p1 cm, the USa group still had a significantly better stone free rate (USa 32.4% vs. FS 17.8%, p=0.028), stone disintegration rate (USa 89.2% vs. FS 54.8%, p<0.001) and retreatment rate (USa 21.6% vs. FS 53.4%, p<0.001) compared with the FS group. However, the complication rates were not statistically different between the two groups (US 2.7% vs. FS 4.1%, p=0.599), but the USa group did still have a lower complication ratio (Table 4). The most common complication was post-SWL-related flank pain (Clavien-Dindo grade I), which occurred in 1 (0.5%) USa group patient and 11 (5.1%) FS group patients, however no cases required hospitalization. In all cases symptoms were controlled with intravenous/intramuscular or oral non-steroidal anti-inflammatory drugs (NSAIDs). In the USa group, 1 patient developed ureteral stone street after SWL; the patient had a 1.7 cm renal stone and required further RIRS for obstruction release and residual stone removal (grade 3). Another patient had a urinary tract infection and required hospitalization for intravenous antibiotics (grade 2). In the FS group, 2 patients developed post-SWL ureteral stone street, and one required URSL for stone removal (grade 3); the other patient had stone passage during follow up (grade 2). Discussion SWL has been the primary treatment option for renal and upper urinary calculi since its introduction in the early 1980’s [20]. Two major international urological associations: the European association of urology and the American urological association both recommend SWL as the treatment of choice for small to intermediate renal stones. However, the treatment has certain limitations which may predict poor treatment efficacy, including steep and narrow infundibulum, long lower pole calyx, and shockwave-resistant stones [21, 22]. To maximize the efficacy and outcomes while minimizing complications of SWL, certain options regarding patient and stone characteristics have been proposed [16]. Obese patients and those with a higher body mass index (BMI) may have a larger skin to stone distance revealed during clinical examination, which could lead to unfavorable SWL success rates [12, 23]. Some studies highlighted the importance of anatomical location and the architecture of the stones as measured by CT Hounsfield units [8-11]. Other evidence showed that during SWL sessions, the energy and frequency emitted by the lithotripter notably contributed to stone disintegration. It is recommended that the treatment strategy starts from a low energy level and low frequency rate, and then gradually increases. Starting from a low energy level has been shown to pre-sensitize the kidney and cause renal vasoconstrictions [13, 24], thus reducing renal damage and improving patient tolerance. Low frequency shock wave rates have been proven to be associated with better stone fragmentation in many previous studies [14, 25-27]. Although there is no gold standard for optimal treatment frequency, it has been shown that frequency rates of 60 shocks per minute (1 Hz) and 90 shocks per minute (1.5 Hz) both had better outcomes compared with 120 shocks per minute (2 Hz) [14, 25-27]. Decreasing both the initial energy and shock wave frequency results in a reduced total number of shock waves and energy being delivered, thus reducing the possible damage to the kidney, and therefore decreasing the possibility of complications and improving patient comfort. The patient could be more easily adapted to this treatment, thus minimizing patient movement and the use of sedative agents. In this way, energy delivery could be more focused on the target and stone disruption could be improved. The training and experience of the technicians and operators performing the procedure also has an impact on the success of an SWL session, studies have shown that the stone free rate improves as the operator completes a learning curve [28, 29]. In the current study, the SWL session starts with a low energy (14KV) and low frequency setting (60Hz) in order to maximize the treatment effect. All of the SWL sessions were performed by the same two technicians who have over 10 years of experience. The authors consider this to be a strength of the current study. Using the same low-frequency, low energy machine setup and having SWL sessions performed by the same two experienced operators, the SWL efficiency could be maximized while minimizing the inter-operator bias and learning curve bias. Last but not least, the impact of the patient’s stability during the SWL session must be considered. Patient movement and respiration during the SWL session can cause kidney movement [17], thus causing shock waves to be misdirected and focused away from the target. Excessive energy and inaccurate shockwaves may cause damage to the parenchyma and adjacent organs. Even when patients are under sedation or anesthesia during SWL, respiration related mistargeting remains inevitable. Constant tracking of the stone under a continuous fluoroscope could be the solution, however this may cause excessive ionizing radiation exposure. To overcome this problem, Chang et al. developed a real-time tracking ultrasound based system for renal stones [30]. In vitro and animal studies [31] showed the system to be efficient, and it could increase the accuracy of renal stone targeting and the efficiency of stone fragmentation. The major advantage that ultrasound provides is real-time tracking of the stone without excessive radiation exposure to the patient. Although the dose of radiation during one SWL session may not be much and is not a worrisome dose compared to other invasive radiological procedures, the cumulative effect of ionizing radiation that needs to take into account includes the pre-treatment diagnostic imaging studies, such as CT or IVU, and possible repeat SWL treatment at a later date. Chen et al. [19] reported on their clinical experience of renal stone treatment using an electromagnetic lithotripter integrated with an ultrasound-based real-time tracking system. Their results demonstrated increased accuracy of stone targeting with less shockwaves applied. Smith et al. [32] also compared the stone free rates between the USa localization technique and the traditional FS localization technique. The results revealed equivalent outcomes using the two different stone localization modalities but with the added benefit of no ionization exposure when using the USa technique. A randomized prospective study conducted by Van Besien et al. [33] demonstrated similar results, with the USa SWL stone-free rate not being inferior to the FS SWL, but with no need for ionizing radiation. This is probably most beneficial in pediatric patients, as children are 2-7 times more radiation-sensitive than adults [34]. In a study evaluating the outcomes and radiation exposure of children with cystine stones, Goren et al. [35] demonstrated that USa SWL was more effective and applied less ionizing radiation doses for pediatric patients. Also, in faintly radiopaque stones, such as cystine stones, USa-guided SWL has better visualization of the stones than a fluoroscope. In the current study, the USa group had a larger baseline stone size. Despite this, the USa group had a significantly better stone-free rate, stone-disintegration rate and a lower retreatment rate; this was regardless of stone size stratification. This result indicates better stone localization and targeting with the assistance of real-time ultrasound, which causes better stone fragmentation and secondarily leads to better stone clearance and lower retreatment rates. As for safety, the USa group had a significantly lower complication rate for smaller stones, and a lower complication rate for larger stones, although this did not reach statistical significance. These results further indicate the theoretical benefit of ultrasound tracking, that is, better accuracy leads to less surrounding tissue damage, which would be more significant in smaller targets. Previously reported stone-free rate of ESWL ranged around 47 to 92% [2-7]. In our study, the main reason of our relative lower stone-free rates is because that stone-free status was more strictly defined. Stone-free status was defined as the absence of radiographic residual stones in the follow-up imaging, any residual fragments visible on KUB was considered as non-stone-free, even the fragments were less than 2mm or 4mm, which was the most commonly used criteria in clinical practice and other studies. Previous studies had certain limitations, such as small patient numbers or a lack of head to head comparisons [19, 32]. Despite its randomized prospective study design, Van Besein’s study failed to show statistical significance between the different localization methods, this may be related to the small number of studied patients. A strength of the current study compared to others is that we have a large number of study patients, two similar energy source lithotripters using the same SWL protocol, and all procedures were performed by the same two experienced technicians, which provides strong head-to-head comparison while minimizing bias between different institutions and operators. However, there were several limitations to the present study that need to be addressed. First, its retrospective study design limited the bias control, such as stone composition and anatomic parameters. Second, radiation exposure was not recorded besides self-reported preference by the two technicians. Third, CT was not routinely in every patient to assess factors that affect ESWL results, such as CT values, stone-to-skin distance and BMI. In addition, we compared two different electromagnetic lithotripters. Different lithotripters' acoustic output, efficiency, and collateral effects vary between models. Therefore, further strictly controlled studies are needed to support the conclusion. Lastly, SWL and localization techniques are very operator-dependent. The current study was conducted in one single center and only two technicians operated the machine, thus minimizing inter-operator and institutional bias. Further studies could be conducted in a larger set of patients who are prospectively randomized. Conclusions SWL is a safe and non-invasive way of treating renal stones. this study compared two electromagnetic shock wave machines with different stone tracking systems. LiteMed LM-9200 ELMA lithotripter, which combined ultrasound and fluoroscopic stone targeting outperformed Medispec EM-1000 lithotripter, which used fluoroscopy for stone localization and tracking, with better stone-free rates and disintegration rates, as well as lower retreatment rates and complications with possible reduced radiation exposure. Declarations Ethics approval and consent to participate The present study, including its research protocols and data collection, were approved by the Mackay Memorial Hospital Institutional Review Board. In view of the retrospective nature of the study, obtaining patients’ informed consent was waived. Consent for publication Not applicable Availability of data and material Records and data pertaining to this study are in the patient’s secure medical records in Mackay Memorial Hospital and are available from the corresponding author on reasonable request. Competing interests The authors declare that they have no competing interests. Fundings None to declare. Authors' contributions THC: project development, data collection, data analysis, and manuscript writing. WRL: data collection and data analysis. WKT: data collection and data analysis. PKC: data collection and data analysis. MC: project development, data analysis, and manuscript editing. JST: project development, data analysis, and manuscript editing. AWC: manuscript editing. All authors have read and approved the manuscript. Acknowledgements Not applicable Abbreviations CT: Computed tomography SWL: shock wave lithotripsy KUB: kidneys, ureter and bladder IVU: intravenous urography URSL: ureteroscopic lithotripsy RIRS: retrograde intrarenal surgery PCNL: percutaneous nephrolithotomy References Chaussy C, Brendel W, Schmiedt E: Extracorporeally induced destruction of kidney stones by shock waves . Lancet (London, England) 1980, 2 (8207):1265-1268. Fialkov JM, Hedican SP, Fallon B: Reassessing the efficacy of the Dornier MFL-5000 lithotriptor . The Journal of urology 2000, 164 (3 Pt 1):640-643. Nafie S, Dyer JE, Minhas JS, Mills JA, Khan MA: Efficacy of a mobile lithotripsy service: a one-year review of 222 patients . Scandinavian journal of urology 2014, 48 (3):324-327. Chung VY, Turney BW: The success of shock wave lithotripsy (SWL) in treating moderate-sized (10-20 mm) renal stones . Urolithiasis 2016, 44 (5):441-444. 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Goren MR, Goren V, Ozer C: Ultrasound-Guided Shockwave Lithotripsy Reduces Radiation Exposure and Has Better Outcomes for Pediatric Cystine Stones . Urologia internationalis 2017, 98 (4):429-435. Tables Table 1: Patient demographics and stone characteristics Characteristic USa FS P value Number of patients 209 216 Patient age (mean±SD) 53.3±13.2 53.8±12.4 0.568 Patient gender 0.016 Male, n (%) 130 (62.2%) 158 (73.1%) Female, n (%) 79 (37.8%) 58 (26.8%) Stone size (cm) 1.03±0.37 0.87±0.33 0.008 >1cm (n) 111 73 <1cm (n) 98 143 Table 2. Overall outcomes, stone free rate, complication, retreatment rate. US (n=209) FS (n=216) P value Stone free rate (%) 91 (43.5) 61 (28.2) <0.001 Disintegrate rate (%) 179 (85.6) 139 (64.3) <0.001 Retreatment rate (%) 31 (14.8) 77 (35.6) <0.001 Complication rate (%) 4 (1.9) 13 (6.0) 0.031 Table 3. Stone size <1cm, outcomes, stone free rate, complication, retreatment rate. US (n=98) FS (n=143) P value Stone free rate (%) 55 (56.1) 48 (33.5) <0.001 Disintegrate rate (%) 80 (81.6) 99 (69.2) 0.031 Retreatment rate (%) 7 (7.1) 38 (26.5) 1cm, outcomes, stone free rate, complication, retreatment rate. US (n=111) FS (n=73) P value Stone free rate (%) 36 (32.4) 13/ (17.8) 0.028 Disintegrate rate (%) 99 (89.2) 40 (54.8) <0.001 Retreatment rate (%) 24 (21.6) 39 (53.4) <0.001 Complication rate (%) 3 (2.7) 3 (4.1) 0.599 Cite Share Download PDF Status: Published Journal Publication published 10 Nov, 2020 Read the published version in BMC Urology → Version 3 posted Reviewer # 1 agreed at journal 30 Sep, 2020 Reviewers invited by journal 25 Sep, 2020 Editor assigned by journal 10 Sep, 2020 Submission checks completed at journal 09 Sep, 2020 Editor invited by journal 09 Sep, 2020 You are reading this latest preprint version Show more versions 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. 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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-24107","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research article","associatedPublications":[],"authors":[{"id":2213207,"identity":"961a30b3-d9ae-4d31-9d2a-8ce0181fa127","order_by":0,"name":"Tsung-Hsin Chang","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tsung-Hsin","middleName":"","lastName":"Chang","suffix":""},{"id":2213208,"identity":"a4fe29af-b25e-4f67-8223-b21ec8867820","order_by":1,"name":"Wun-Rong Lin","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Wun-Rong","middleName":"","lastName":"Lin","suffix":""},{"id":2213209,"identity":"a002dd79-ed3d-485a-944d-d97398899cfd","order_by":2,"name":"Wei-Kung Tsai","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Wei-Kung","middleName":"","lastName":"Tsai","suffix":""},{"id":2213210,"identity":"0e520232-0d12-48b0-a729-6ee3690c38b1","order_by":3,"name":"Pai-Kai Chiang","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Pai-Kai","middleName":"","lastName":"Chiang","suffix":""},{"id":2213211,"identity":"2b5c72fa-cbe9-4ba9-90cb-3be15d39fd0a","order_by":4,"name":"Marcelo Chen","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Marcelo","middleName":"","lastName":"Chen","suffix":""},{"id":2213212,"identity":"3369390c-d1af-4864-b128-4cb6541f9612","order_by":5,"name":"Jen-Shu Tseng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuUlEQVRIiWNgGAWjYJACAwYGGyDF2HiABC0JaSAtDcRrYWBIOAymiNNicPvwgcKfP87brW0/DLSlxiaasJZzaQnGPAm3k7edSQRqOZaW20BQyxkeA2MGoBazA0AtjA2HidNi+CPhXLLZ+YckaDHgSThgZ3aDWFskz7AB/ZKWnGB2A2hLAjF+4TvDfMzwh42dvdn59IcPPtTYENYCBGzA2GdIBKtMIEI5CDA/ABL2RCoeBaNgFIyCkQgAP8dF9Kr0jfAAAAAASUVORK5CYII=","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Jen-Shu","middleName":"","lastName":"Tseng","suffix":""},{"id":2213213,"identity":"85473d75-f355-40ea-81ac-dcae6b40f4c5","order_by":6,"name":"Allen W Chiu","email":"","orcid":"","institution":"Mackay Memorial Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Allen","middleName":"W","lastName":"Chiu","suffix":""}],"badges":[],"createdAt":"2020-04-21 11:44:03","currentVersionCode":3,"declarations":"","doi":"10.21203/rs.3.rs-24107/v3","doiUrl":"https://doi.org/10.21203/rs.3.rs-24107/v3","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12894-020-00756-6","type":"published","date":"2020-11-10T15:01:49+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":13590566,"identity":"8f8acc19-e166-4fbe-aa9a-fb33520bfabc","added_by":"auto","created_at":"2021-09-17 05:05:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":992983,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-24107/v3/83ab2196-cdbf-4840-acce-83d267dcda25.pdf"}],"financialInterests":"","formattedTitle":"\u003cp\u003eComparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones\u003c/p\u003e","fulltext":[{"header":"Background","content":"\u003cp\u003eExtracorporeal shock wave lithotripsy (SWL) has been used as a non-invasive method of urolithiasis management since the 1980\u0026rsquo;s [1]. It has been proven to be a safe, efficient way of treating non-infected upper urinary tract stones and remains one of the most commonly used treatment modality for renal stones worldwide today.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Contemporary studies have shown that the success rate of SWL for renal stones ranges from 47 to 92% [2-7]. This highly variable result is due to various crucial factors, including stone composition and size [8-11], skin to stone distance [12], lithotripter energy power [13] and frequency [14, 15], patient positioning [16], and patient tolerance and respiration [16, 17]. Less than half of the administered shockwaves may be accurately focused on the targeted calculus [18], and the excessive energy and shockwaves can cause damage to the parenchyma and adjacent organs. Chen et al. [19] demonstrated increased accuracy of stone targeting by using an electromagnetic lithotripter integrated with both ultrasound real-time tracking system and traditional fluoroscopy (LiteMed LM-9200 ELMA). Through the alternative use of ultrasound and fluoroscopy, the energy of the lithotripter may be more focused on the target stone during the whole session, thus increasing SWL efficiency. However, only a few studies have compared the efficacy of ultrasound-based lithotripters with fluoroscopy-based lithotripters. It is difficult to compare efficacy between different institutions due to variabilities in treatment protocols and operators. The current study compared the efficacy and clinical outcomes of two electromagnetic lithotripters using different stone localization methods (LiteMed LM-9200 ELMA lithotripter: combined ultrasound and fluoroscopic stone targeting; Medispec EM-1000 lithotripter: pure fluoroscopic stone targeting), in a single center with 2 hospital branches, using the same group of urologists and the same set of patients and surgical indications. The machines were operated by the same two experienced technicians, which minimizes operator and institutional related bias.\u003c/p\u003e\n\u003cp\u003eThe aim of the current study was to compare the efficacy and clinical outcomes of these two different stone localization modalities in the treatment of renal stones in one single medical center.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u0026nbsp; The present study retrospectively reviewed the medical records of patients with radio-opaque kidney stones with stone size between 0.5 to 2.0 cm who underwent SWL in a single medical center with 2 hospital branches between January 2013 and March 2019. Exclusion criteria were patients with congenital anomalies or urinary diversion, pediatric patients or patients who received SWL as a combination therapy with other treatment modalities. Patients with radiolucent stones were also excluded as plain x-rays were used as the standard follow-up modality.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; All patients underwent imaging and laboratory studies prior to SWL. Plain abdominal radiography of the kidneys, ureter and bladder (KUB), renal sonography, intravenous urography (IVU) and abdominal computed tomography (CT) were used to diagnose and identify the stones. The size of the stones were measured on the KUB using maximal stone diameters.\u003c/p\u003e\n\u003cp\u003ePatients underwent SWL at two branches of our medical center with either a LiteMed LM-9200 ELMA lithotripter or Medispec LTD EM-1000 lithotripter, depending on their location. The distance between the two branches of our medical center were about 10 km with about a 20 minute driving time and both were located in the northern part of the city. There were no regional characteristics different between the patients of the two branches, such as water composition and eating habits. The energy source of both lithotripters was an electromagnetic shockwave source. The focal length was 145mm for EM-1000 and 125mm for LM-9200. All SWL treatments were performed on an ambulatory basis by the same group of urologists. Both machines were operated by the same two experienced technicians. The LiteMed LM-9200 ELMA lithotripter used ultrasonography and fluoroscopy for dual focusing of stone localization and tracking, while the EM1000 machine used only fluoroscopy for stone visualization, with an integrated computerized fluoroscopic X-ray (Visionspec\u003csup\u003eTM\u003c/sup\u003e). The LiteMed LM-9200 machine has a auto-firing system, the shockwaves will only be fired when the stone is in the focal zone.\u003c/p\u003e\n\u003cp\u003eThe same standardized SWL protocol was used for both machines except for the stone localization method. The patient was placed in a supine position without a restraint belt. The cushion size and lubricating jelly used were the same in both branch. and the stone was located by the fluoroscopy in both group. In the USa group, ultrasound was combined use for dual stone localization before initiating the SWL session and during the treatment for real time tracking of the stone. While in the FS group, only pure fluoroscopy was used throughout the whole session. During SWL, the initial energy level was set at 14KV and could gradually increased up to 19 KV if the stones did not show adequate fragmentation under low energy settings. The shock wave rate was set at 60 shocks per minute for both lithotripters. The maximum number of shockwaves delivered in one session was 3,000. Light intravenous propofol and dormicum were used as analgesics or for sedation if the patient suffered from pain or could not tolerate lying still in the supine position throughout the SWL session. The patient\u0026rsquo;s position was adjusted throughout the SWL session for better stone visualization. If the patient\u0026rsquo;s stone is still in focal zone, the position of the patient will not be changed to avoid constant de-coupling and re-coupling. In the FS group, the position was checked and adjusted after every 600 shocks or when the patient moved. While in the USa group, positioning was adjusted based on the ultrasound tracking of the stone location throughout the SWL session. All patient received SWL sessions on an ambulatory basis, analgesics with Diclofenac or Acetaminophen were prescribed for post-operative pain control.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Patients were evaluated at 4, 12 and 24 weeks after the SWL session by KUB. Stone-free status was defined as the absence of radiographic residual stones in the follow-up imaging, any residual fragments visible on KUB was considered as non-stone-free. The KUB x-ray. Stone disintegration was defined as the presence of stone destruction, fragmentation or a decrease in size in the post-session KUB compared with the pre-session KUB. Retreatment was defined as the need for further surgical intervention (repeat SWL, rigid ureteroscopic lithotripsy (URSL), retrograde intrarenal surgery (RIRS) or percutaneous nephrolithotomy (PCNL)) for symptomatic patients or patients with residual stone fragments \u0026gt;0.5 cm. Complications were classified according to the Clavien-Dindo classification system. All data were analyzed and compared using t-tests and chi-squared tests with IBM SPSS statistics version 25.0 software. Statistical significance was set at P\u0026lt;0.05.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; The present study, including its research protocols and data collection, were approved by the Mackay Memorial Hospital Institutional Review Board. All personal information was de-identified prior to data analysis, thus ensuring patient data confidentiality.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eOf the 425 included patients, 209 were treated with USa SWL and 216 were treated with FS SWL. The mean age of patients was 53.3\u0026plusmn;13.2 years in the USa group and 53.8\u0026plusmn;12.4 years in the FS group (p=0.538). Comparison of the two groups revealed that the FS group was significantly more male dominated (p=0.016) and there were significantly larger stones in the USa group (1.03\u0026plusmn;0.37cm vs. 0.87\u0026plusmn;0.33cm, p\u0026lt;0.005) (Table 1).\u003c/p\u003e\n\u003cp\u003eStatistical analysis revealed better treatment outcomes in the USa group. The overall stone free rate was significantly better in the USa group compared with the FS group (USa 43.5% vs. FS 28.2%, p\u0026lt;0.001), and the overall stone disintegration rates were significantly higher (USa 85.6% vs. FS 64.3%, p\u0026lt;0.001). Significant lower retreatment (USa 14.8% vs. FS 35.6%, p\u0026lt;0.001) and complication rates (USa 1.9% vs. FS 5.5%, p=0.031) were noted in the USa group compared with the FS group (Table 2).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Patients were further stratified by stone size ( \u0026lt;1cm and \u0026ge; 1cm), and the results were similar following stratification. In the group with renal stones \u0026lt;1cm the USa group had a significantly higher stone free rate (USa 56.1% vs. FS 33.5%, p\u0026lt;0.001) and stone disintegration rate (USa 81.6% vs. FS 69.2%, p=0.031) compared with the FS group. The USa group also had a significantly lower retreatment rate (USa 7.1% vs. FS 26.5%, p\u0026lt;0.001) and complication rate (USa 1.0% vs. FS 6.9%, p=0.029) (Table 3).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; In the group with stones \u0026gt;1 cm, the USa group still had a significantly better stone free rate (USa 32.4% vs. FS 17.8%, p=0.028), stone disintegration rate (USa 89.2% vs. FS 54.8%, p\u0026lt;0.001) and retreatment rate (USa 21.6% vs. FS 53.4%, p\u0026lt;0.001) compared with the FS group. However, the complication rates were not statistically different between the two groups (US 2.7% vs. FS 4.1%, p=0.599), but the USa group did still have a lower complication ratio (Table 4).\u003c/p\u003e\n\u003cp\u003eThe most common complication was post-SWL-related flank pain (Clavien-Dindo grade I), which occurred in 1 (0.5%) USa group patient and 11 (5.1%) FS group patients, however no cases required hospitalization. In all cases symptoms were controlled with intravenous/intramuscular or oral non-steroidal anti-inflammatory drugs (NSAIDs). In the USa group, 1 patient developed ureteral stone street after SWL; the patient had a 1.7 cm renal stone and required further RIRS for obstruction release and residual stone removal (grade 3). Another patient had a urinary tract infection and required hospitalization for intravenous antibiotics (grade 2). In the FS group, 2 patients developed post-SWL ureteral stone street, and one required URSL for stone removal (grade 3); the other patient had stone passage during follow up (grade 2).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSWL has been the primary treatment option for renal and upper urinary calculi since its introduction in the early 1980\u0026rsquo;s [20]. Two major international urological associations: the European association of urology and the American urological association both recommend SWL as the treatment of choice for small to intermediate renal stones. However, the treatment has certain limitations which may predict poor treatment efficacy, including steep and narrow infundibulum, long lower pole calyx, and shockwave-resistant stones [21, 22].\u003c/p\u003e\n\u003cp\u003eTo maximize the efficacy and outcomes while minimizing complications of SWL, certain options regarding patient and stone characteristics have been proposed [16]. Obese patients and those with a higher body mass index (BMI) may have a larger skin to stone distance revealed during clinical examination, which could lead to unfavorable SWL success rates [12, 23]. Some studies highlighted the importance of anatomical location and the architecture of the stones as measured by CT Hounsfield units [8-11].\u003c/p\u003e\n\u003cp\u003eOther evidence showed that during SWL sessions, the energy and frequency emitted by the lithotripter notably contributed to stone disintegration. It is recommended that the treatment strategy starts from a low energy level and low frequency rate, and then gradually increases. Starting from a low energy level has been shown to pre-sensitize the kidney and cause renal vasoconstrictions [13, 24], thus reducing renal damage and improving patient tolerance. Low frequency shock wave rates have been proven to be associated with better stone fragmentation in many previous studies [14, 25-27]. Although there is no gold standard for optimal treatment frequency, it has been shown that frequency rates of 60 shocks per minute (1 Hz) and 90 shocks per minute (1.5 Hz) both had better outcomes compared with 120 shocks per minute (2 Hz) [14, 25-27]. Decreasing both the initial energy and shock wave frequency results in a reduced total number of shock waves and energy being delivered, thus reducing the possible damage to the kidney, and therefore decreasing the possibility of complications and improving patient comfort. The patient could be more easily adapted to this treatment, thus minimizing patient movement and the use of sedative agents. In this way, energy delivery could be more focused on the target and stone disruption could be improved. The training and experience of the technicians and operators performing the procedure also has an impact on the success of an SWL session, studies have shown that the stone free rate improves as the operator completes a learning curve [28, 29].\u003c/p\u003e\n\u003cp\u003eIn the current study, the SWL session starts with a low energy (14KV) and low frequency setting (60Hz) in order to maximize the treatment effect. All of the SWL sessions were performed by the same two technicians who have over 10 years of\u0026nbsp; experience. The authors consider this to be a strength of the current study. Using the same low-frequency, low energy machine setup and having SWL sessions performed by the same two experienced operators, the SWL efficiency could be maximized while minimizing the inter-operator bias and learning curve bias.\u003c/p\u003e\n\u003cp\u003eLast but not least, the impact of the patient\u0026rsquo;s stability during the SWL session must be considered. Patient movement and respiration during the SWL session can cause kidney movement [17], thus causing shock waves to be misdirected and focused away from the target. Excessive energy and inaccurate shockwaves may cause damage to the parenchyma and adjacent organs. Even when patients are under sedation or anesthesia during SWL, respiration related mistargeting remains inevitable. Constant tracking of the stone under a continuous fluoroscope could be the solution, however this may cause excessive ionizing radiation exposure. To overcome this problem, Chang et al. developed a real-time tracking ultrasound based system for renal stones [30]. \u003cem\u003eIn vitro\u003c/em\u003e and animal studies [31] showed the system to be efficient, and it could increase the accuracy of renal stone targeting and the efficiency of stone fragmentation.\u003c/p\u003e\n\u003cp\u003eThe major advantage that ultrasound provides is real-time tracking of the stone without excessive radiation exposure to the patient. Although the dose of radiation during one SWL session may not be much and is not a worrisome dose compared to other invasive radiological procedures, the cumulative effect of ionizing radiation that needs to take into account includes the pre-treatment diagnostic imaging studies, such as CT or IVU, and possible repeat SWL treatment at a later date.\u003c/p\u003e\n\u003cp\u003eChen et al. [19] reported on their clinical experience of renal stone treatment using an electromagnetic lithotripter integrated with an ultrasound-based real-time tracking system. Their results demonstrated increased accuracy of stone targeting with less shockwaves applied. Smith et al. [32] also compared the stone free rates between the USa localization technique and the traditional FS localization technique. The results revealed equivalent outcomes using the two different stone localization modalities but with the added benefit of no ionization exposure when using the USa technique. A randomized prospective study conducted by Van Besien et al. [33] demonstrated similar results, with the USa SWL stone-free rate not being inferior to the FS SWL, but with no need for ionizing radiation. This is probably most beneficial in pediatric patients, as children are 2-7 times more radiation-sensitive than adults [34]. In a study evaluating the outcomes and radiation exposure of children with cystine stones, Goren et al. [35] demonstrated that USa SWL was more effective and applied less ionizing radiation doses for pediatric patients. Also, in faintly radiopaque stones, such as cystine stones, USa-guided SWL has better visualization of the stones than a fluoroscope.\u003c/p\u003e\n\u003cp\u003eIn the current study, the USa group had a larger baseline stone size. Despite this, the USa group had a significantly better stone-free rate, stone-disintegration rate and a lower retreatment rate; this was regardless of stone size stratification. This result indicates better stone localization and targeting with the assistance of real-time ultrasound, which causes better stone fragmentation and secondarily leads to better stone clearance and lower retreatment rates. As for safety, the USa group had a significantly lower complication rate for smaller stones, and a lower complication rate for larger stones, although this did not reach statistical significance. These results further indicate the theoretical benefit of ultrasound tracking, that is, better accuracy leads to less surrounding tissue damage, which would be more significant in smaller targets.\u003c/p\u003e\n\u003cp\u003ePreviously reported stone-free rate of ESWL ranged around 47 to 92% [2-7]. In our study, the main reason of our relative lower stone-free rates is because that stone-free status was more strictly defined. Stone-free status was defined as the absence of radiographic residual stones in the follow-up imaging, any residual fragments visible on KUB was considered as non-stone-free, even the fragments were less than 2mm or 4mm, which was the most commonly used criteria in clinical practice and other studies.\u003c/p\u003e\n\u003cp\u003ePrevious studies had certain limitations, such as small patient numbers or a lack of head to head comparisons [19, 32]. Despite its randomized prospective study design, Van Besein\u0026rsquo;s study failed to show statistical significance between the different localization methods, this may be related to the small number of studied patients. A strength of the current study compared to others is that we have a large number of study patients, two similar energy source lithotripters using the same SWL protocol, and all procedures were performed by the same two experienced technicians, which provides strong head-to-head comparison while minimizing bias between different institutions and operators.\u003c/p\u003e\n\u003cp\u003eHowever, there were several limitations to the present study that need to be addressed. First, its retrospective study design limited the bias control, such as stone composition and anatomic parameters. Second, radiation exposure was not recorded besides self-reported preference by the two technicians. Third, CT was not routinely in every patient to assess factors that affect ESWL results, such as CT values, stone-to-skin distance and BMI. In addition, we compared two different electromagnetic lithotripters. Different lithotripters' acoustic output, efficiency, and collateral effects vary between models. Therefore, further strictly controlled studies \u0026nbsp;are needed to support the conclusion. Lastly, SWL and localization techniques are very operator-dependent. The current study was conducted in one single center and only two technicians operated the machine, thus minimizing inter-operator and institutional bias. Further studies could be conducted in a larger set of patients who are prospectively randomized.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eSWL is a safe and non-invasive way of treating renal stones. this study compared two electromagnetic shock wave machines with different stone tracking systems. LiteMed LM-9200 ELMA lithotripter, which combined ultrasound and fluoroscopic stone targeting outperformed Medispec EM-1000 lithotripter, which used fluoroscopy for stone localization and tracking, with better stone-free rates and disintegration rates, as well as lower retreatment rates and complications with possible reduced radiation exposure.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eEthics approval and consent to participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe present study, including its research protocols and data collection, were approved by the Mackay Memorial Hospital Institutional Review Board. In view of the retrospective nature of the study, obtaining patients\u0026rsquo; informed consent was waived.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent for publication\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAvailability of data and material\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eRecords and data pertaining to this study are in the patient\u0026rsquo;s secure medical records in Mackay Memorial Hospital and are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFundings\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNone to declare.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAuthors' contributions\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTHC: project development, data collection, data analysis, and manuscript writing. WRL: data collection and data analysis. WKT: data collection and data analysis. PKC: data collection and data analysis. MC: project development, data analysis, and manuscript editing. JST: project development, data analysis, and manuscript editing. AWC: manuscript editing.\u003c/p\u003e\n\u003cp\u003eAll authors have read and approved the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCT: Computed tomography\u003c/p\u003e\n\u003cp\u003eSWL: shock wave lithotripsy\u003c/p\u003e\n\u003cp\u003eKUB: kidneys, ureter and bladder\u003c/p\u003e\n\u003cp\u003eIVU: intravenous urography\u003c/p\u003e\n\u003cp\u003eURSL: ureteroscopic lithotripsy\u003c/p\u003e\n\u003cp\u003eRIRS: retrograde intrarenal surgery\u003c/p\u003e\n\u003cp\u003ePCNL: percutaneous nephrolithotomy\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eChaussy C, Brendel W, Schmiedt E: \u003cstrong\u003eExtracorporeally induced destruction of kidney stones by shock waves\u003c/strong\u003e. \u003cem\u003eLancet (London, England) \u003c/em\u003e1980, \u003cstrong\u003e2\u003c/strong\u003e(8207):1265-1268.\u003c/li\u003e\n\u003cli\u003eFialkov JM, Hedican SP, Fallon B: \u003cstrong\u003eReassessing the efficacy of the Dornier MFL-5000 lithotriptor\u003c/strong\u003e. \u003cem\u003eThe Journal of urology \u003c/em\u003e2000, \u003cstrong\u003e164\u003c/strong\u003e(3 Pt 1):640-643.\u003c/li\u003e\n\u003cli\u003eNafie S, Dyer JE, Minhas JS, Mills JA, Khan MA: \u003cstrong\u003eEfficacy of a mobile lithotripsy service: a one-year review of 222 patients\u003c/strong\u003e. \u003cem\u003eScandinavian journal of urology \u003c/em\u003e2014, \u003cstrong\u003e48\u003c/strong\u003e(3):324-327.\u003c/li\u003e\n\u003cli\u003eChung VY, Turney BW: \u003cstrong\u003eThe success of shock wave lithotripsy (SWL) in treating moderate-sized (10-20 mm) renal stones\u003c/strong\u003e. \u003cem\u003eUrolithiasis \u003c/em\u003e2016, \u003cstrong\u003e44\u003c/strong\u003e(5):441-444.\u003c/li\u003e\n\u003cli\u003eNielsen TK, Jensen JB: \u003cstrong\u003eEfficacy of commercialised extracorporeal shock wave lithotripsy service: a review of 589 renal stones\u003c/strong\u003e. \u003cem\u003eBMC urology \u003c/em\u003e2017, \u003cstrong\u003e17\u003c/strong\u003e(1):59.\u003c/li\u003e\n\u003cli\u003eAbdel-Khalek M, Sheir KZ, Mokhtar AA, Eraky I, Kenawy M, Bazeed M: \u003cstrong\u003ePrediction of success rate after extracorporeal shock-wave lithotripsy of renal stones--a multivariate analysis model\u003c/strong\u003e. \u003cem\u003eScandinavian journal of urology and nephrology \u003c/em\u003e2004, \u003cstrong\u003e38\u003c/strong\u003e(2):161-167.\u003c/li\u003e\n\u003cli\u003eLee CC, Lin WR, Hsu JM, Chow YC, Tsai WK, Chiang PK, Chen M, Chiu AW: \u003cstrong\u003eComparison of electrohydraulic and electromagnetic extracorporeal shock wave lithotriptors for upper urinary tract stones in a single center\u003c/strong\u003e. \u003cem\u003eWorld journal of urology \u003c/em\u003e2019, \u003cstrong\u003e37\u003c/strong\u003e(5):931-935.\u003c/li\u003e\n\u003cli\u003eEl-Nahas AR, El-Assmy AM, Mansour O, Sheir KZ: \u003cstrong\u003eA prospective multivariate analysis of factors predicting stone disintegration by extracorporeal shock wave lithotripsy: the value of high-resolution noncontrast computed tomography\u003c/strong\u003e. \u003cem\u003eEuropean urology \u003c/em\u003e2007, \u003cstrong\u003e51\u003c/strong\u003e(6):1688-1693; 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localization is as effective as fluoroscopy\u003c/strong\u003e. \u003cem\u003eUrology annals \u003c/em\u003e2016, \u003cstrong\u003e8\u003c/strong\u003e(4):454-457.\u003c/li\u003e\n\u003cli\u003eVan Besien J, Uvin P, Hermie I, Tailly T, Merckx L: \u003cstrong\u003eUltrasonography Is Not Inferior to Fluoroscopy to Guide Extracorporeal Shock Waves during Treatment of Renal and Upper Ureteric Calculi: A Randomized Prospective Study\u003c/strong\u003e. \u003cem\u003eBioMed research international \u003c/em\u003e2017, \u003cstrong\u003e2017\u003c/strong\u003e:7802672.\u003c/li\u003e\n\u003cli\u003eRichardson RB: \u003cstrong\u003eStem cell niches and other factors that influence the sensitivity of bone marrow to radiation-induced bone cancer and leukaemia in children and adults\u003c/strong\u003e. \u003cem\u003eInternational journal of radiation biology \u003c/em\u003e2011, \u003cstrong\u003e87\u003c/strong\u003e(4):343-359.\u003c/li\u003e\n\u003cli\u003eGoren MR, Goren V, Ozer C: \u003cstrong\u003eUltrasound-Guided Shockwave Lithotripsy Reduces Radiation Exposure and Has Better Outcomes for Pediatric Cystine Stones\u003c/strong\u003e. \u003cem\u003eUrologia internationalis \u003c/em\u003e2017, \u003cstrong\u003e98\u003c/strong\u003e(4):429-435.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"font-family: Calibri, sans-serif; color: rgb(0, 0, 0);\"\u003eTable 1:\u003c/span\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;Patient demographics and stone characteristics \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ctable style=\"border-collapse:collapse;border:none;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eCharacteristic\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eUSa\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eFS\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eP value\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eNumber of patients\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e209\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e216\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003ePatient age\u0026nbsp;(mean\u0026plusmn;SD)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e53.3\u0026plusmn;13.2\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e53.8\u0026plusmn;12.4\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.568\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003ePatient gender\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.016\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-indent:24.0pt;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eMale, n (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e130 (62.2%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e158 (73.1%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-indent:24.0pt;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eFemale, n (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e79 (37.8%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e58 (26.8%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eStone size (cm)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e1.03\u0026plusmn;0.37\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.87\u0026plusmn;0.33\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.008\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp; \u0026nbsp; \u0026gt;1cm (n)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e111\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e73\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125.9pt;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp; \u0026nbsp; \u0026lt;1cm (n)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e98\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e143\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96.3pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eTable 2. Overall outcomes, stone free rate, complication, retreatment rate.\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ctable style=\"border-collapse:collapse;border:none;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eUS\u0026nbsp;(n=209)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eFS\u0026nbsp;(n=216)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eP value\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eStone free rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e91 (43.5)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e61 (28.2)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eDisintegrate rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e179 (85.6)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e139 (64.3)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eRetreatment rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e31 (14.8)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e77 (35.6)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eComplication rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e4 (1.9)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e13 (6.0)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.031\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eTable 3. Stone size \u0026lt;1cm, outcomes, stone free rate, complication, retreatment rate.\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ctable style=\"border-collapse:collapse;border:none;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eUS\u0026nbsp;(n=98)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eFS\u0026nbsp;(n=143)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eP value\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eStone free rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e55 (56.1)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e48 (33.5)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eDisintegrate rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e80 (81.6)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e99 (69.2)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.031\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eRetreatment rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e7 (7.1)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e38 (26.5)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eComplication rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e1 (1.0)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e10 (6.9)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.029\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eTable 4. Stone size \u0026gt;1cm, outcomes, stone free rate, complication, retreatment rate.\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ctable style=\"border-collapse:collapse;border:none;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eUS\u0026nbsp;(n=111)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eFS\u0026nbsp;(n=73)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: 1pt solid windowtext;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-image: initial;border-left: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eP value\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eStone free rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e36 (32.4)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e13/ (17.8)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.028\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eDisintegrate rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e99 (89.2)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e40 (54.8)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eRetreatment rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e24 (21.6)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e39 (53.4)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e\u0026lt;0.001\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 1.65in;border-right: 1pt solid windowtext;border-bottom: 1pt solid windowtext;border-left: 1pt solid windowtext;border-image: initial;border-top: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003eComplication rate (%)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e3 (2.7)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.65pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e3 (4.1)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99.7pt;border-top: none;border-left: none;border-bottom: 1pt solid windowtext;border-right: 1pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;line-height:200%;font-size:16px;font-family:\"Times New Roman\",serif;text-align:center;vertical-align:baseline;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-family: Calibri, sans-serif;\"\u003e0.599\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\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":"bmc-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"buro","sideBox":"Learn more about [BMC Urology](http://bmcurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/buro/default.aspx","title":"BMC Urology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Shock wave lithotripsy, nephrolithiasis, Kidney, ultrasonography","lastPublishedDoi":"10.21203/rs.3.rs-24107/v3","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-24107/v3","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eIn this study, we aimed to compare the efficacy and clinical outcomes of shock wave lithotripsy (SWL) for patients with renal stones using pure fluoroscopy (FS) or ultrasound-assisted (USa) localization with two lithotripters.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe retrospectively identified 425 patients with renal calculi who underwent SWL with either a LiteMed LM-9200 ELMA lithotripter (209 cases), which combined ultrasound and fluoroscopic stone targeting or a Medispec EM-1000 lithotripter machine (216 cases), which used fluoroscopy for stone localization and tracking. The patient demographic data, stone-free rates, stone disintegration rates, retreatment rates and complication rates were analyzed.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe USa group had a significantly higher overall stone-free rate (43.6 vs. 28.2%, p\u0026lt;0.001) and stone disintegration rate (85.6 vs. 64.3%, p\u0026lt;0.001), as well as a significantly lower retreatment rate (14.8 vs. 35.6%, p\u0026lt;0.001) and complication rate (1.9 vs. 5.5%, p=0.031) compared with the FS group. This superiority remained significant in the stone size \u0026lt;1cm stratified group. In the stone size \u0026gt;1cm group, the stone-free rate (32.4 vs. 17.8%, p=0.028), disintegration rate (89.2 vs. 54.8%, p=0.031) and retreatment rate (21.6 vs. 53.4%, p\u0026lt;0.001) were still significantly better in the USa group, however there was no significant difference in the complication rate. The most common complication was post-SWL-related flank pain.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eSWL is a safe and non-invasive way of treating renal stones. this study compared two electromagnetic shock wave machines with different stone tracking systems. LiteMed LM-9200 ELMA lithotripter, which combined ultrasound and fluoroscopic stone targeting outperformed Medispec EM-1000 lithotripter, which used fluoroscopy for stone localization and tracking, with better stone-free rates and disintegration rates, as well as lower retreatment rates and complications with possible reduced radiation exposure.\u003c/p\u003e","manuscriptTitle":"Comparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones","msid":"","msnumber":"","nonDraftVersions":[{"code":3,"date":"2020-09-11 19:43:52","doi":"10.21203/rs.3.rs-24107/v3","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2020-09-30T12:00:00+00:00","index":1,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2020-09-25T12:00:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2020-09-10T12:00:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2020-09-09T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2020-09-09T12:00:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"buro","sideBox":"Learn more about [BMC Urology](http://bmcurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/buro/default.aspx","title":"BMC Urology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}},{"code":2,"date":"2020-08-08 18:04:56","doi":"10.21203/rs.3.rs-24107/v2","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2020-09-07T12:00:00+00:00","index":1,"fulltext":"Recommendation: Major revisions required\nForm responses:\n---\n\nComments to Author:\n---\nThe authors have addressed most of my remarks, but did not address my general comment about the most important shortcoming of the study (repeated below). I do not believe the paper should be published without addressing this issue.\n\nFrom previous review: 'There is a major flaw in the way the data is interpreted in this paper. The article claims to be comparing two different methods of guidance, but it does so using two different lithotripters. Because lithotripters' acoustic output, efficiency, and collateral effects vary between models, it is not possible to conclude as the authors have done that the tracking system is the reason for improved outcomes. Because of this issue, the paper should not be published in its current form. The title, conclusions,and other parts of the paper need to be altered to reflect that this clinical trial compares the two systems which potentially have many differences between them, including their method of tracking.'\n\n\n\n* Publons Reviewer Recognition. Springer Nature can send verification of this review directly to Publons (a subsidiary of Clarivate Analytics). If you would like to take advantage of this service, please click on the “Yes” option below. Your name, email address, title of the reviewed manuscript, name of the journal, and date of your review submission (the “Review Data”) will then be transmitted to Publons upon publication of the manuscript. If you have already registered at Publons, they will notify you of the receipt of this review and update your profile as per your settings and their policy. If you are not registered with Publons, you will receive an email from them asking you to register in order for them to be able to recognize your review on your new profile page. Publons may use the Review Data to generate derivative metadata for the benefit of Publons and you as a reviewer, carefully considering the sensitivity of such information. For example, Publons may verify your record as a reviewer by updating your profile published on its webservice if you have registered for such service or help editors to identify candidate reviewers. Please find the details of processing in Publons’ privacy policy https://publons.com/about/terms: **No**\n* Please confirm that you have included your review in the ‘Comments to Author’ box?: **\nYes**\n* Should the manuscript be highlighted for promotional activity?: **No**\n* Declaration of competing interests: **Yes. I have equity in and am a consultant for SonoMotion, Inc, a startup company that produces technology for stone management. I do not have any other competing interests.**\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please do not publish my name with my report. (default)**\n* Is the study design appropriate to answer the research question (including the use of appropriate controls), and are the conclusions supported by the evidence presented?: **No**\n* Are the methods sufficiently described to allow the study to be repeated?: **Yes**\n* Is the use of statistics and treatment of uncertainties appropriate?: **Yes**\n* Is the presentation of the work clear?: **Yes**\n* Are the images in this manuscript (including electrophoretic gels and blots) free from apparent manipulation?: **Yes**\n"},{"type":"decision","content":"Major revision","date":"2020-09-07T12:00:00+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2020-08-07T12:00:00+00:00","index":1,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2020-08-06T12:00:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2020-08-03T12:00:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2020-08-02T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2020-08-02T12:00:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"buro","sideBox":"Learn more about [BMC Urology](http://bmcurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/buro/default.aspx","title":"BMC Urology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2020-05-08 14:18:01","doi":"10.21203/rs.3.rs-24107/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2020-07-29T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2020-07-27T12:00:00+00:00","index":3,"fulltext":"Recommendation: Major revisions required\nForm responses:\n---\n\nComments to Author:\n---\nThis manuscript describes a clinical trial comparing two lithotripters, one with real-time ultrasound tracking + fluoroscopy guidance and one with only fluoroscopic guidance. The paper is clearly written and the study appears to effectively compare the two machines, although a few additional critical details are needed for an adequate comparison.\n\nHowever, there is a major flaw in the way the data is interpreted in this paper. The article claims to be comparing two different methods of guidance, but it does so using two different lithotripters. Because lithotripters' acoustic output, efficiency, and collateral effects vary between models, it is not possible to conclude as the authors have done that the tracking system is the reason for improved outcomes. Because of this issue, the paper should not be published in its current form. The title, conclusions, and other parts of the paper need to be altered to reflect that this clinical trial compares the two systems which potentially have many differences between them, including their method of tracking.\n\nSpecific Remarks:\n\nPage 5, Line 17: It is not clear that shock wave lithotripsy is the most commonly used treatment for urinary stones. Ureteroscopy is now the most common treatment in many countries. Please include a supporting citation or alter the text.\n\nPage 5, Line 52: Please briefly describe what type of tracking the LiteMed system has. Is it a passive tracking system (e.g. gates the output so the shocks are only emitted when the stone is in focus), or does it actively move the focus to keep the stone and focus aligned?\n\nPage 7, Lines 47 - 58: More details are needed for the reader to adequately compare the two lithotripter sources. Please state the following information for each lithotripter:Lateral and axial beam widths, source aperture and focal length, peak pressures of the shock wave at the operated voltage\n\nPage 8, Line 50: It is stated that the maximum number of shocks was 3,000. Did this vary from patient to patient? If so, the average number of shocks for each group should be included and compared to determine if they were significantly different.\n\nPage 9, Line 8: How was the patient position adjusted and how was coupling maintained during the adjustment?\n\nPage 9, Line 26: Did the authors consider patients with small residual fragments (\u003c 2 mm) stone free? This is common in lithotripsy research. What is the limit of resolution for the KUB x-ray?\n\nTable 2: Can you please explain why the stone free rates are quite low for both lithotripters? It is common many systems to achieve 60-70%. This is concerning because it suggests either some significant difference in how stone-free status is reported, or both lithotripters' output or technique used in the study may differ substantially from others.\n\nPage 17, Line 19: The authors note that two technicians operated the machines. Were there any differences in outcomes between the two technicians? Did one technician operate one machine or did each operate both in some cases?\n\nPage 17, Line 47: The authors note that damage to the kidney occurs for inaccurate shock waves, but it should be noted that all shock waves can damage the kidney, even when targeted to the stone, because the focus of the lithotripter is always targeting some kidney tissue in addition to the stone.\n\n\n* Publons Reviewer Recognition. Springer Nature can send verification of this review directly to Publons (a subsidiary of Clarivate Analytics). If you would like to take advantage of this service, please click on the “Yes” option below. Your name, email address, title of the reviewed manuscript, name of the journal, and date of your review submission (the “Review Data”) will then be transmitted to Publons upon publication of the manuscript. If you have already registered at Publons, they will notify you of the receipt of this review and update your profile as per your settings and their policy. If you are not registered with Publons, you will receive an email from them asking you to register in order for them to be able to recognize your review on your new profile page. Publons may use the Review Data to generate derivative metadata for the benefit of Publons and you as a reviewer, carefully considering the sensitivity of such information. For example, Publons may verify your record as a reviewer by updating your profile published on its webservice if you have registered for such service or help editors to identify candidate reviewers. Please find the details of processing in Publons’ privacy policy https://publons.com/about/terms: **No**\n* Please confirm that you have included your review in the ‘Comments to Author’ box?: **\nYes**\n* Should the manuscript be highlighted for promotional activity?: **No**\n* Declaration of competing interests: **I hold stock in and am a consultant for SonoMotion, Inc, a company that is developing ultrasound technology to treat kidney stone disease and may in the future compete with the lithotripter systems described in this article.\n\nI do not have any other financial or non-financial competing interests.**\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please do not publish my name with my report. (default)**\n* Is the study design appropriate to answer the research question (including the use of appropriate controls), and are the conclusions supported by the evidence presented?: **No**\n* Are the methods sufficiently described to allow the study to be repeated?: **No**\n* Is the use of statistics and treatment of uncertainties appropriate?: **Yes**\n* Is the presentation of the work clear?: **Yes**\n* Are the images in this manuscript (including electrophoretic gels and blots) free from apparent manipulation?: **Yes**\n"},{"type":"editorInvitedReview","content":"","date":"2020-07-26T12:00:00+00:00","index":2,"fulltext":"Recommendation: Major revisions required\nForm responses:\n---\n\nComments to Author:\n---\nGeneral comments,\nThis manuscript is a retrospective analysis of the results of treatment for renal stones using SWL devices with two different targeting methods by two surgeons. As a result, targeting combined with US has shown a significant success rate, and it is evaluated as useful content to bring SWL to the spotlight again not only in reducing radiation exposure but also in the technique of stone surgery which is being biased toward URS. However, the method for demonstrating the superiority of US targeting needs to be corrected due to the lack of required information.\n\nMajor;\n1. The two SWL devices are described as electromagnetic shock waves, but are there any differences in their focal length and focal size? The cushion size also affects the energy transfer.\nDid you use a degassing type jelly? Is LiteMed LM-9200 an outline type or an inline type?\nWithout a well-equipped device background, except for ultrasound, you can't conclude that treatment results were affected only by the US. Please include that information in the Method section as it is the part that is the basis of this research.\nIf there are differences in these parameters depending on the model, consider them in the Discussion section and list them as Limitations.\n\n2. There is no mention of the patient restraint belt in the text. This belt is essential for conscious SWL as it limits the patient's movements. Please state whether it was used or not.\nIf you do not know if it was used or not, please describe it in Limitaion.\n\n3. Why was the male predominant among the groups in terms of patient background? And why do you think the sizes are different?\nDo the centers where each device is installed exist in different areas?\nDoes the center for finding stones differ from center to center? For example, is it because the diagnosis of calculi is due to a physical examination or a medical checkup?\nAre there any differences in the composition of water and the regional characteristics of eating habits?\nExamine them and show the calculus component within the range that can be understood.\nIn addition, since CT images are taken, it is essential to present data regarding factors that affect ESWL results, such as CT values, SSD, and BMI.\n\n4. Why are the complications different between groups?\nWhat is the stone size for your SWL prestenting adaptation? When performing SWL on a 1.7 cm stone, I think that stenting is essential.\nConsider these points as they are important for safe SWL enforcement.\n\n5. You mention in the discussion the importance of Training, but Okada et al. describe the importance and usefulness of training in ultrasound-combined targeting.\nPlease cite this paper.\nOkada A, Yasui T, Taguchi K, et al. Impact of official technical training for urologists on the efficacy of shock wave lithotripsy. Urolithiasis. 2013;41(6):487-492. doi:10.1007/s00240-013-0586-3\n\nMinor;\nAll Tables should be listed after the text, not in the middle.\n* Publons Reviewer Recognition. Springer Nature can send verification of this review directly to Publons (a subsidiary of Clarivate Analytics). If you would like to take advantage of this service, please click on the “Yes” option below. Your name, email address, title of the reviewed manuscript, name of the journal, and date of your review submission (the “Review Data”) will then be transmitted to Publons upon publication of the manuscript. If you have already registered at Publons, they will notify you of the receipt of this review and update your profile as per your settings and their policy. If you are not registered with Publons, you will receive an email from them asking you to register in order for them to be able to recognize your review on your new profile page. Publons may use the Review Data to generate derivative metadata for the benefit of Publons and you as a reviewer, carefully considering the sensitivity of such information. For example, Publons may verify your record as a reviewer by updating your profile published on its webservice if you have registered for such service or help editors to identify candidate reviewers. Please find the details of processing in Publons’ privacy policy https://publons.com/about/terms: **Yes**\n* Please confirm that you have included your review in the ‘Comments to Author’ box?: **\nYes**\n* Should the manuscript be highlighted for promotional activity?: **No**\n* Declaration of competing interests: **I declare that I have no competing interests.**\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please do not publish my name with my report. (default)**\n* Is the study design appropriate to answer the research question (including the use of appropriate controls), and are the conclusions supported by the evidence presented?: **No**\n* Are the methods sufficiently described to allow the study to be repeated?: **No**\n* Is the use of statistics and treatment of uncertainties appropriate?: **Yes**\n* Is the presentation of the work clear?: **Yes**\n* Are the images in this manuscript (including electrophoretic gels and blots) free from apparent manipulation?: **Yes**\n"},{"type":"reviewerAgreed","content":"","date":"2020-07-03T12:00:00+00:00","index":3,"fulltext":""},{"type":"reviewerAgreed","content":"","date":"2020-07-01T12:00:00+00:00","index":2,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2020-06-10T12:00:00+00:00","index":1,"fulltext":"Recommendation: Reject\nForm responses:\n---\n\nComments to Author:\n---\nPlease overwrite this text when adding your comments to the authors.\nThis is a good study however not of value as a quick search on the pubmed reveals a number of papers published on the topic..\nIn fact a large series published in BJUI in year 2016 had a similar findings in Over 1000 patients.\nThe utility of ultrasound in assessing and monitoring the progress of swl is unquestioned.It is particularly useful in children.\nGoing forward a future direction could be a comparison between RIRS with SWl(usg) guided in pediatric population.\nTo summarise, a good study but not suitable for publication as it does not add anything to what already exists.* Please confirm that you have included your review in the ‘Comments to Author’ box?: **\nYes**\n* Are the methods appropriate and well described to allow independent reproduction of experiments?: **Yes**\n* Does the work include the necessary controls?: **Yes**\n* Are you able to assess the statistics?: **\nThis question is not applicable to this manuscript**\n* Are the conclusions drawn adequately supported by the data shown?: **Yes**\n* Quality of written English: **Needs some language corrections before being published**\n* Should the manuscript be highlighted for promotional activity?: **No**\n* Declaration of competing interests: **I declare that I have no competing interests**\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please do not publish my name with my report. (default)**\n"},{"type":"reviewerAgreed","content":"","date":"2020-05-23T12:00:00+00:00","index":1,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2020-05-20T12:00:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2020-05-01T12:00:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2020-04-28T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2020-04-27T12:00:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"buro","sideBox":"Learn more about [BMC Urology](http://bmcurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/buro/default.aspx","title":"BMC Urology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0fecd1aa-99aa-4871-8bd8-637472728276","owner":[],"postedDate":"September 11th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":496699,"name":"Urology \u0026 Nephrology"}],"tags":[],"updatedAt":"2020-11-15T15:03:30+00:00","versionOfRecord":{"articleIdentity":"rs-24107","link":"https://doi.org/10.1186/s12894-020-00756-6","journal":{"identity":"bmc-urology","isVorOnly":false,"title":"BMC Urology"},"publishedOn":"2020-11-10 15:01:49","publishedOnDateReadable":"November 10th, 2020"},"versionCreatedAt":"2020-09-11 19:43:52","video":"","vorDoi":"10.1186/s12894-020-00756-6","vorDoiUrl":"https://doi.org/10.1186/s12894-020-00756-6","workflowStages":[]},"version":"v3","identity":"rs-24107","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-24107","identity":"rs-24107","version":["v3"]},"buildId":"cBFmMYwuxLRRLfASyISRj","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}