Stone Location Research Articles

Three-dimensional visualization technology for guiding one-step percutaneous transhepatic cholangioscopic lithotripsy for the treatment of complex hepatolithiasis.

Biliary stone disease is a highly prevalent condition and a leading cause of hospitalization worldwide. Hepatolithiasis with associated strictures has high residual and recurrence rates after traditional multisession percutaneous transhepatic cholangioscopic lithotripsy (PTCSL). To study one-step PTCSL using the percutaneous transhepatic one-step biliary fistulation (PTOBF) technique guided by three-dimensional (3D) visualization. This was a retrospective, single-center study analyzing, 140 patients who, between October 2016 and October 2023, underwent one-step PTCSL for hepatolithiasis. The patients were divided into two groups: The 3D-PTOBF group and the PTOBF group. Stone clearance on choledochoscopy, complications, and long-term clearance and recurrence rates were assessed. Age, total bilirubin, direct bilirubin, Child-Pugh class, and stone location were similar between the 2 groups, but there was a significant difference in bile duct strictures, with biliary strictures more common in the 3D-PTOBF group (P = 0.001). The median follow-up time was 55.0 (55.0, 512.0) days. The immediate stone clearance ratio (88.6% vs 27.1%, P = 0.000) and stricture resolution ratio (97.1% vs 78.6%, P = 0.001) in the 3D-PTOBF group were significantly greater than those in the PTOBF group. Postoperative complication (8.6% vs 41.4%, P = 0.000) and stone recurrence rates (7.1% vs 38.6%, P = 0.000) were significantly lower in the 3D-PTOBF group. Three-dimensional visualization helps make one-step PTCSL a safe, effective, and promising treatment for patients with complicated primary hepatolithiasis. The perioperative and long-term outcomes are satisfactory for patients with complicated primary hepatolithiasis. This minimally invasive method has the potential to be used as a substitute for hepatobiliary surgery.

Factors and nomograms determining the effectiveness of extracorporeal shock wave lithotripsy in children with urolithiasis: a literature review

Extracorporeal shock wave lithotripsy (ESWL) is currently the priority method for treating urolithiasis in children. Due to the lack of extended indications for the application of this technique, an active search has been made over the past 30 years to define factors predicting ESWL outcome, to create objective preoperative planning tools, to increase ESWL effectiveness and to reduce the number of anesthetics and unnecessary surgical interventions. Search for the information on predictive factors of ESWL successful intervention and on modern statistical tools predicting lithotripsy effectiveness in children with urolithiasis was made in foreign and domestic sources, like MEDLINE, eLIBRARY, CyberLeninka. The literature analysis has showed that the following factors predispose positive ESWL outcomes: age before six years, smaller calculi size, and shorter skin-to-stone distance. Stone location in the lower calyx group, multiple concrements, and their high density has a negative impact at complete fragment detachment after ESWL. The probability of complete detachment of stone fragments from the lower calyx group decreases under the following anatomic features of kidney collecting system: number of draining calyces is more than one, calyx neck diameter is less than 4 mm, acute angle between the lower infundibulum and renal pelvis. Body mass index and prestenting have a controversial effect at successful ESWL too. Nomograms and scoring systems based on predicting factors are widely used in both adult and pediatric practice. The two most commonly used nomograms in pediatric urology are Onal and Dogan nomograms developed in 2012 and 2015 in Turkey. These nomograms include the following parameters: patient's sex and age, history of ipsilateral surgical interventions as well as stone localization, number and size. Thus, predicting ESWL outcomes using preoperative planning allows to choose the most appropriate treatment modality for a particular patient considering his/her individual anatomical and physiological characteristics and characteristics of the calculi.

Endourological society fellowship program: a real contribution to improve surgical outcomes of stone patients treated with ureteroscopy.

We assessed the impact of the one-year endourological society fellowship program (ESFP) on the achievement of optimal surgical outcomes (OSO) in stone patients treated with ureteroscopy (URS). We identified 303 stone patients treated with URS from January 2018 to June 2022 by five experienced surgeons (ES). Of those, two attended ESFP. OSO was defined as the presence of residual fragments ≤ 4mm at 1-month post-operative imaging (Ultrasound + X - Ray or CT scan). Descriptive statistics explored patients' characteristics and the rate of OSO according to the attendance of ESFP. Uni- and multivariate logistic regression analyses (UVA and MVA) tested the impact of stone characteristics, surgical data, ESFP, and imaging technique on the rate of OSO. The LOWESS curve explored the graphical association between stone size and the multivariable-adjusted probability of OSO in the two groups of surgeons. Of 303 patients, 208 (69%) were treated by the two surgeons who attended ESFP. OSO was achieved in 66% and 52% of patients treated by ES with and without ESFP, respectively (p = 0.01). At UVA, ESFP (OR = 1.78; 95% CI = 1.09-2.90), stone diameter (OR = 0.92; 95% CI = 0.88-0.96), stone location (kidney vs. ureter; OR = 0.34; 95% CI = 0.21-0.58), imaging technique (CT scan vs. Ultrasound + X-Ray; OR = 0.28; 95% CI = 0.16-0.47) predicted OSO achievement (all p < 0.05). At MVA analyses, ESFP was associated with OSO (OR = 2.24; 95% CI = 1.29-3.88; p < 0.05), along with the other aforementioned variables. The LOWESS curve showed that the greater the stone size, the greater the difference in OSO in the two groups of surgeons. ESFP positively affects OSO achievement after URS, especially in patients with a high stone burden.

Fixed parotid sialoliths: surgical treatment via transfacial approach using sialendoscopy and ultrasound guidance—retrospective cohort study

The most common cause of symptomatic parotitis is the obstruction of its duct, most commonly by a stone. Despite the development of minimally invasive endoscopic techniques, some of these obstructions cannot be treated entirely endoscopically, requiring combined approaches. This study reviewed the outcomes and surgical technique of ultrasound-guided transfacial parotid sialolithotomy following a failed endoscopic approach. Conducted as a case series with retrospective chart review at an academic tertiary care center, the study evaluated patients who underwent this combined transfacial-endoscopic operation for symptomatic parotid sialolithiasis from April 2022 through January 2023. Key outcomes included operative technique, stone size, stone location, complications, and symptom relief. A total of four male patients with a mean age of 66 years underwent the ultrasound-guided transfacial operation for symptomatic parotid sialolithiasis. Needle localization facilitated transfacial stone retrieval in all cases. The follow-up period ranged from 6 to 15 months. Stone locations included the proximal one-third of the ductal lumen (1 patient), the parotid hilum (1 patient), and within the gland parenchyma (2 patients). The average sialolith length was 8 ± 1.4 mm, and the width was 3 ± 0.8 mm. The average surgical time was 113 ± 16.5 minutes. All cases (100%) achieved successful stone retrieval and symptomatic improvement, with complete resolution of symptoms in 3 cases (75%). No major complications were reported. Ultrasound-guided transfacial parotid sialolithotomy is a safe and effective alternative to parotidectomy for patients who have failed a purely endoscopic approach. A novel transfacial surgical dissection method, based on the middle premasseter space, is proposed for accessing the main parotid duct when obstructions are located in the middle portion of the duct.

Urological Challenges during Pregnancy: Current Status and Future Perspective on Ureteric Stent Encrustation.

The management of ureter hydronephrosis and urolithiasis during pregnancy has been changed by the adoption of ureteric stents. Despite their broad use for several other conditions, from emergency to elective settings, their complications cannot be ignored. Being most prevalent during pregnancy, urinary tract infections and stent encrustations are particularly common and can affect either fetal growth or maternal-fetal homeostasis, leading to obstetric complications. The main concern associated with ureteric stents is the indwelling time, which could represent the potential trigger of those complications. However, to ensure the optimal management of a ureteric stent during pregnancy, factors such as the grading of encrustations and the presence, size, and location of stones should be evaluated in pre-operative planning. As a consequence, a multimodal approach, including obstetrics, gynecologists, urologists, and nurses, is essential to ensure a complication-free procedure and successful ureteric stent removal. Finally, future research should focus on utilizing biodegradable and biocompatible materials to reduce and even eliminate the complications related to forgotten stents in order to reduce the financial burden associated with stent replacement and the management of stent-encrustation-related complications.

Assessment of Factors Responsible for Stone-Free Status After Retrograde Intrarenal Surgery.

Aim The study aimed to evaluate the predictive factors that determined stone-free rate (SFR) after retrograde intrarenal surgery (RIRS). Materials and methods This prospective study was conducted on 183 patients undergoing RIRS for renal stones. Patients were categorized into two groups, depending on stone-free status one month following the procedure. SFRwas defined as the complete absence of stones or stones <4 mm. The parameters studied included patient demographics, presence of hydronephrosis, presence of preoperative double J-stent, abnormal renal anatomy, and stone characteristics (stone burden, stone number, stone density, stone location, lower pole infundibulopelvic angle, and lower pole renal infundibular length (RIL)). Univariate and multivariate analyses were performed to identify risk factors for residual stones. We assessed the predictive ability of the RIRS score and Resorlu-Unsal stone score (RUSS) for evaluating SFR utilizing receiver operating characteristic (ROC) analysis. Results 183 patients were included inthe study with a median age of 51 years. 131 (71.6%) patients were declared stone-free after the procedure. The mean stone size and density were 16.9 SD±7.5 mm and 1038 SD±342 Hounsfield units (HU) respectively. Stone-free patients had lower stone size (14.3 mm vs. 23.6 mm, p<0.01) and stone density (970 HU vs. 1211 HU, p<0.01) compared to non-stone-free patients. Patients with residual stones had steeper lower pole renal infundibulopelvic angle (RIPA) (31.3° vs. 40.7°, p<0.01) and longer RIL(26.6 mm vs. 21.1 mm, p<0.01). Stone multiplicity (p<0.01), lower pole stone location (p<0.01), and renal malformations (p<0.01)were significant influencing factors for residual renal stones after RIRS. Multivariate analysis revealed stone size, stone density (HU), and stone location as independent predictors for SFR after RIRS. Among the scoring systems, the RIRS score had the highest diagnostic accuracy for SFR (area under the curve (AUC): -0.882, 95% CI-0.828-0.936). Conclusion Stone size, stone density (HU), and stone number are important predictors of SFR after RIRS. Lower pole stone location and abnormal renal anatomy play a substantial role in determining SFR after RIRS. In lower pole stones, a long RIL and acute RIPA negatively influence SFR. Additionally, the RIRS score was found to be a better predictor for SFR than the RUSS score.

Comparison between mini-percutaneous nephrolithotomy and retrograde intra renal surgery for the management of lower calyceal calculi of size less than 1.5 cm : Our institutional experience

Background: The treatment of lower calyceal calculi with a size &lt;1.5 cm remains a subject of debate. Mini-percutaneous nephrolithotomy (Mini PCNL) and retrograde intrarenal surgery (RIRS) are both effective options, but there is a need for comparative analysis to determine the optimal approach. Mini-perc has the advantage of direct visualization and efficient fragmentation and clearance, while RIRS is a minimally invasive technique with excellent visualization and minimal morbidity. Aims and Objectives: This study aims to evaluate and compare the efficacy, safety, and outcomes of mini-perc PCNL and RIRS in the management of lower calyceal calculi. Materials and Methods: This retrospective comparative cohort study included a total of 72 patients with lower calyceal calculi &lt;1.5 cm. Thirty-six patients underwent mini-perc, and 36 patients underwent RIRS. Results: No significant differences were observed in patient demographic characteristics, stone size, or stone location between the mini-perc and RIRS groups. The mini-perc group had a significantly higher stone-free rate (SFR) (94.4%) compared to the RIRS group (86.1%) (P&lt;0.05). The mini-perc technique had a higher success rate in first-session stone clearance (88.9%) compared to RIRS (77.8%) (P&lt;0.05). The mini-perc group had a longer operative time, higher estimated blood loss, and a longer post-operative hospital stay compared to the RIRS group (P&lt;0.05). Conclusion: Both mini-perc and RIRS techniques are effective for managing lower calyceal calculi &lt;1.5 cm. Mini-perc offers a SFR and a better success rate in first-session stone clearance compared to RIRS. However, mini-perc procedures are associated with longer operative time, higher estimated blood loss, and a longer post-operative hospital stay.

An analysis of the predictive factors for stone clearance at primary ureteroscopy

BackgroundUreteric colic is a common emergency urological presentation [1]. When operative intervention is required, retrograde ureteroscopy is the most common approach. There are multiple treatment strategies including primary ureteroscopy (URS), staged ureteroscopy, and deferred ureteroscopy following ureteric stent placement. The approach is based on a number of clinical and stone factors. This study assesses the factors which predict stone clearance at the initial procedure.AimsAll patients diagnosed with an obstructing ureteric stone who were managed operatively in a consecutive 12-month period were included. Patients were evaluated for stone clearance following a single or multiple procedures. A number of factors including stone size, location, gender, age and pre-operative laboratory results were evaluated for association with stone clearance at index procedure. Multivariate logistic regression analyses were performed to produce odds ratios (OR) with confidence interval (CI) at 95% and significance values P < 0.05.ResultsOne hundred and seventy patients were included in the final analysis. Stone clearance following the index procedure was achieved in 57% (n = 100) of patients. Predictors of successful stone clearance at index procedure were stone size < 6 mm, male gender and distal stone location (p < 0.05). Proximal stone location, stone size > 10 mm and elevated c-reactive protein (CRP) were associated respectively with multiple procedures to achieve stone clearance (p < 0.05).ConclusionsAcute ureteric stones can be managed with a number of treatment strategies. This study identifies factors which predict stone clearance at index procedure. These results will help urologists accurately counsel patients when undertaking operative management for ureteric colic.

Досвід лікування конкрементів сечовидільних шляхів у дітей

Aim - to analyze the treatment of children with urolithiasis (urolithiasis), taking into account the location of stones in the urinary tract, their size and density, to select further individual patient management tactics. Materials and methods. The study included 48 patients with single urinary tract stones aged 6 months to 18 years. X-ray structural analysis and determination of the chemical composition was carried out with 39 stone fragments. Results. In 5 (10.4%) patients with calculi in the distal part of the ureter up to 5 mm in size, medical expulsive therapy was started. 17 (35.4%) patients with kidney and ureter calculi measuring 6-14 mm and density up to 900 HU underwent extracorporeal shock wave lithotripsy. In 3 (6.3%) patients with kidney and ureter calculi 6-14 mm in size and with a density of more than 900 HU, ureterorenoscopy (URS) and extraction using a Dormia basket or forceps to capture fragments were performed. 20 (41.7%) children with kidney stones larger than 15 mm or density greater than 1200 HU underwent contact lithotripsy. Contact endovesical lithotripsy was performed in 2 (4.2%) patients with massive calculi in the urinary bladder who underwent cystoplasty for an exstrophy-epispadias malformation. Results of X-ray structural stones analysis: calcium oxalate (wevelite, wedelite) - 31 (79.5%), calcium phosphate (hydroxyapatite) - 5 (12.8%), brushite - 2 (5.1%), cystine - 1 (2.6%). Conclusions. Modern minimally invasive technologies make it possible to remove calculi of any density and localization from the urinary system in a minimally traumatic, effective and sufficiently safe manner, regardless of the age of the child. In the treatment of urolithiasis in children, it is advisable to follow a personalized approach with the step-by-step use of the optimal arsenal of means to remove the stone. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the local ethics committee of the listed institution. Informed consent of children and their parents was obtained for the research. No conflict of interest was declared by the authors.

Exploring the potential of combined B-mode features and color Doppler ultrasound in the diagnosis of ureteric stone as an alternative to ionizing radiation exposure by computed tomography.

To assess the diagnostic efficacy of integrating B-mode and color Doppler capabilities of ultrasound (US) to establish a robust standalone diagnostic tool for the diagnosis of ureteric stones as an alternative to non-contrast-enhanced computed tomography (NCCT). A total of 140 consecutive patients diagnosed with ureteric stones using NCCT were enrolled. On the same day, US in both B-mode and Color Doppler was performed by an experienced radiologist who was blinded to the NCCT scan results. The diagnostic rate of US for stone detection was recorded. Additionally, baseline patient and stone characteristics were analyzed for their association with the accuracy of stone detection using US. US exhibited a high sensitivity of 91.43%, detecting 128 out of 140 stone foci. Notably, ureteric stones in the proximal and uretero-vesical junction (UVJ) segments were readily identifiable compared to those in the pelvic region (p = 0.0003). Additionally, hydronephrosis enhanced the US's ability to detect stones (p < 0.0001). Conversely, abdominal gases and obesity adversely affected US capabilities (p < 0.0001 and p = 0.009, respectively). Stone side, size, and density showed no statistically significant impact (p > 0.05). US with its color Doppler capabilities could serve as a reliable and safe alternative imaging modality in the diagnostic work up of patients with ureterolithiasis. Factors including stone location, Hydronephrosis, weight and abdominal gases significantly influenced its accuracy.

Defining a learning curve for urology trainees to achieve renal access without complications in endoscopic combined intrarenal surgery.

There is a lack of data on the number of surgeries required for endoscopic combined intrarenal surgery (ECIRS). Accordingly, we aimed to identify the learning curve for ECIRS performed by multiple surgeons. We included 296 patients who underwent ECIRS at our university hospital between 2016 and 2021. A learning curve for percutaneous nephrolithotomy side was calculated considering urology-resident surgeons. The learning curve was retrospectively analyzed for surgical time, renal puncture time, stone-free rate, and complications and corrected for age, body mass index, stone size, computed tomography value, cumulative number of surgeries, and stone location. This study included cases performed by 32 surgeons, including 30 residents and 2 attending surgeons. The median number of surgeries performed by the residents and attending surgeons prior to this study was 4.5 and 90, respectively. The median number of surgical procedures performed during the training period was seven. The surgical time of the residents decreased as the number of cases increased, reaching a median surgical time of 111 min for the attending surgeons after 16.4 cases. Renal puncture time was achieved in 20.1 cases. Complications related to renal access were observed in 13.0% (34 patients), Clavien-Dindo grade II in 1.9% (5 patients), and grade III or higher in 0.8% (2 patients). Comparing the first to fifth cases with the 21st and subsequent cases, the complication rate improved from 35% to 13%. Our study demonstrated that ECIRS training provided 16-20 cases with a learning curve to achieve acceptable surgical outcomes.

A 1.9 mm Trilogy lithotripter in mini percutaneous nephrolithotomy Description of technique and case outcomes.

We aimed to evaluate the novel use of a 1.9 mm Trilogy lithotripter probe with varying locations and composition of renal stones. We prospectively enrolled patients to undergo mini percutaneous nephrolithotomy (mPCNL) procedures using the 1.9 mm (instead of the standard 1.5 mm) Trilogy probe from August 2021 to April 2022. Several adjunctive irrigation measures compensated for reduced flow with the larger probe. The primary outcome was treatment efficiency. Patient demographics, preoperative demographics, and comorbidities, as well as real-time surgical data were extracted. Statistical analysis was performed using Kruskal-Wallis tests to compare stone type and location. A total of 110 patients were included in this study. The median total treatment time was 6.8 minutes, median lithotripsy time was 3.3 minutes, median stone treatment efficiency was 0.34 mm/min, and treatment efficacy was 50.4 (lithotripter time/treatment time). Overall median lithotripter efficiency was 104.6 mm3/min. Treatment efficiency was similar among stone composition (p=0.245) and location (p=0.263). Lithotripter 3D and 1D efficiency was also similar among stone composition (p=0.637 and p=0.766, respectively). Lithotripter 1D efficiency was nearly twice as fast in the lower pole compared to other stone locations (p=0.010). The overall broken probe rate for this procedure was 12%, mostly at the beginning, suggesting a learning curve. Five patients had minor complications, including one patient who required admission to the hospital for postoperative pain management. The 1.9 mm Trilogy lithotripter can be effective in mPCNL procedures with the use of easily implementable adjunctive irrigation techniques, decreasing the gap between lithotripsy time and total treatment time.

Bedside Sonography in the Assessment of Suspected Nephrolitiasis

Background: Nephrolithiasis, commonly referred to as kidney stones, is a prevalent urological condition frequently encountered in emergency settings. Rapid and accurate diagnosis is critical for effective management. Bedside sonography has emerged as a valuable diagnostic tool for assessing renal colic and detecting kidney stones due to its non-invasive nature and immediate availability. Objective: To evaluate the diagnostic accuracy and practicality of bedside sonography in suspected cases of nephrolithiasis, particularly in emergency department settings, and to assess its impact on patient management. Methods: A cross-sectional study was conducted at Mahaban Medical and Research Hospital, Swabi, KP, Pakistan, including 72 patients with suspected nephrolithiasis. Bedside sonography was performed using a Toshiba prime ultrasound machine with convex (3.0-5.0 MHz) and linear (7.0-14.0 MHz) transducers. Clinical data, including patient history and symptomatology, were collected and analyzed using SPSS version 25.0. The study focused on identifying the presence, location, and size of kidney stones and correlating these findings with clinical outcomes. Results: Among the 72 participants, 42 (58.3%) had a history of kidney stones. Bedside sonography revealed stone locations as follows: bilateral in 5 (6.9%), left kidney in 27 (37.5%), right kidney in 36 (50.0%), and no stones in 4 (5.6%). The high prevalence of kidney stones, particularly in the right kidney, highlights the importance of BUS in initial evaluations. Conclusion: Bedside sonography is an effective diagnostic tool for nephrolithiasis, providing immediate and detailed information without patient discomfort. Its implementation in emergency settings can enhance patient management, allowing for timely diagnosis and treatment. Further research is warranted to explore the broader applications and long-term outcomes associated with BUS.

The efficacy and safety of ureteroscopic lithotripsy and flexible ureteroscopy with continuous anticoagulant or antiplatelet drugs: A multicenter retrospective real-world study

Abstract Objective The objective of this study is to assess the effectiveness and safety of ureteroscopic lithotripsy and flexible ureteroscopy (fURS) for treating patients on anticoagulant (AC) or antiplatelet (AP) medications. Patients and Methods The study included 213 patients with urinary stones who underwent ureteroscopic lithotripsy or fURS between January 2019 and October 2022 at the Shanghai Municipal Hospital Urology Specialist Alliance. Among these patients, 15 received AC therapy, 193 received AP therapy, and 5 received both AC and AP therapy. Patients were divided into 3 groups based on the real-world management of antithrombotic drugs: the continuation group (n = 62), the discontinuation group (n = 91), and the discontinuation and bridge heparin group (n = 60). Intraoperative and postoperative outcomes were compared among the 3 groups. Results Age, sex, body mass index, stone location, stone size, stone side, and residual fragments were not different among the groups. None of the patients received blood transfusions or had thromboembolic events, emergencies for gross hematuria, significant bleeding-related complications, or unplanned secondary ureteroscopic surgery. The mean duration of hospital stay of the continuation group (3.97 days) was significantly lower than that of the discontinuation group (5.99 days) and the discontinuation and bridge heparin group (5.75 days) (p &lt; 0.001). Conclusions Ureteroscopic lithotripsy and fURS can be performed safely and effectively in patients on AC or AP drugs, resulting in reduced duration of hospital stay.

Are renal stone protocol computed tomography reports giving us enough information?

Non-contrast computed tomography (CT) is the gold-standard diagnostic test for urolithiasis. Little is published regarding which information needs to be included in the report for it to be most useful to the healthcare team for efficient triage and high-quality patient care. This study aimed to assess the quality and variability of CT scan reporting at a single Canadian tertiary academic medical center. We completed a retrospective review of 100 consecutive renal colic CT scans. Descriptive statistics were used to report the frequency with which specific elements commonly used by urologists to triage and treat patients were included in radiology reports. Our sample had a mean age of 51.4±13.1 years. Stone size was universally reported for obstructing stones but was less frequently reported for non-obstructing stones (100% vs. 86.8%). A similar trend was observed for the exact stone number (100% vs. 93.4%). Non-obstructing stones were more likely than obstructing stones to be reported in one dimension (77.5% vs. 47%). Obstructing stones were reported in three dimensions 27% of the time. CT reports commonly include the presence or absence of hydronephrosis status (98%) but are less likely to include renal size (32%) and periureteral stranding (16%). Hounsfield units (HU) were reported in 3% of the reports, but skin-to-stone distance (SSD) and radiation dose were never reported. Reports routinely included assessments of stone size, location, and number (although not uniformly). HU, SSD, and radiation dose were rarely reported. This provides insight into opportunities for standardized reporting to optimize knowledge transfer that may result in clinical efficiency and improved quality of patient care.

Predicting the Efficacy of Repeated Shockwave Lithotripsy for Treating Patients with Upper Urinary Tract Calculi Using an Artificial Neural Network Model.

To establish a prediction model for repeated shockwave lithotripsy (SWL) efficacy to help choose an appropriate treatment plan for patients with a single failed lithotripsy, reducing their treatment burden. The clinical records and imaging data of 304 patients who underwent repeat SWL for upper urinary tract calculi (UUTC) at the Urology Centre of Shiyan People's Hospital between April 2019 and April 2023 were retrospectively collected. This dataset was divided into training (N = 217; 146 males [67.3%] and 71 females [32.7%]) and validation (N = 87; 66 males [75.9%] and 21 females [24.1%]) sets. The overall predictive accuracy of the models was calculated separately for the training and validation. Receiver operating characteristic (ROC) curves were plotted, and the area under the ROC curve (AUC) was calculated. The normalized importance of each independent variable (derived from the one-way analyses) in the input layer of the artificial neural network (ANN) model for the dependent variable (success or failure in repeat SWL) in the output layer was plotted as a bar chart. This study included 304 patients, of whom 154 (50.7%) underwent successful repeat SWL. Predictive models were constructed in the training set and assessed in the validation set. Fourteen influencing factors were selected as input variables to build an ANN model: age, alcohol, body mass index, sex, hydronephrosis, hematuria, mean stone density (MSD), skin-to-stone distance (SSD), stone heterogeneity index (SHI), stone volume (SV), stone retention time, smoking, stone location, and urinary irritation symptom. The model's AUC was 0.852 (95% confidence interval (CI): 0.8-0.9), and its predictive accuracy for stone clearance in the validation group was 83.3%. The order of importance of the independent variables was MSD > SV > SSD > stone retention time > SHI. Establishing an ANN model for repeated SWL of UUTC is crucial for optimizing patient care. This model will be pivotal in providing accurate treatment plans for patients with an initial unsuccessful SWL treatment. Moreover, it can significantly enhance the success rate of subsequent SWL treatments, ultimately alleviating patients' treatment burden.

ESWL EFFICACY FOR VARIOUS DENSITY STONES (HU) ON PLAIN CT SCAN

Extracorporeal Shock Wave Lithotripsy (ESWL) is a keystone in the harmless management of urinary tract stones, offering a viable alternative to surgical mediation for patients pained by urolithiasis. Objectives: The study aims to find the ESWL efficacy for various density stones (HU) on plain CT scans. Methods: This observational study was conducted at CMH Lahore from February 17, 2024, to May 16, 2024. Data were collected from 180 patients suffering from renal stones. Males represented 60% (108 patients), while females 40% (72 patients). Predominantly, stones were located in the renal pelvis (45%), followed by the upper ureter (30%) and lower ureter (25%). The mean stone size was 10 mm, ranging from 5 to 20 mm, with a corresponding mean stone density of 900 Hounsfield Units (HU) as measured on Plain CT Scan. Results: Data were collected from 180 patients. The mean age of the patients was 50.98±2.34 years. There were 60% male and 40% female patients. According to stone location, 45% are located at the renal pelvis, 30 at the upper ureter and 25% at the lower ureter. A mean reduction in the stone size of 65% post-treatment underscores the procedure's ability to facilitate stone disintegration. Stone-free rates varied based on stone density, with higher rates observed for stones with lower densities: 85% for stones ≤ 700 HU, 75% for stones &gt; 700 HU and ≤ 1000 HU, and 65% for stones &gt; 1000 HU. Conclusion: It is concluded that an accurate assessment of stone density and ESWL score is vital in directing treatment decisions and upgrading outcomes for patients going through ESWL for urinary stones. These findings highlight the importance of personalised treatment approaches and the potential of the ESWL score as an essential tool in clinical practice.

#1029 Factors associated with chronic kidney disease in patients with recurrent kidney stones: a case-control study

Abstract Background and Aims Kidney stones have been described in multiple studies as an independent risk factor for chronic kidney disease (CKD). However, this relationship remains partially understood, and there is limited local, regional, and national information available. While common factors contribute to both kidney stones and CKD development, other factors favoring CKD occurrence in patients with recurrent renal lithiasis have been reported. This study aimed to identify factors associated with chronic kidney disease in patients with recurrent renal lithiasis in the city of Cartagena, Colombia. Method This was an observational nested case-control study within a cohort, where cases were patients diagnosed with recurrent kidney stones who developed CKD during follow-up, and controls were patients with recurrent kidney stones without CKD during follow-up. The cohort comprised all adult patients with recurrent kidney stones between 2010 and 2019, without an initial diagnosis of CKD, and with a minimum follow-up period of two years or more. Data on demographic variables (age, gender, type of insurance), clinical factors (overweight, history of hyperuricemia, diabetes mellitus, hypertension, dyslipidemia, alcohol consumption, smoking, exercise habits), and variables related to recurrent kidney stones (course of kidney stones, onset time of CKD, metabolic disorders, history of renal colic, stone localization, number, and size) were collected. Variables associated with the development of chronic kidney disease were identified using association measures via the chi-square test. Variables of clinical and statistical significance were further analyzed for association using multivariable logistic regression. Results The study included 31 cases and 39 controls, with mean ages of 65.2±11.5 and 51.8±14.6 years, respectively (p=0.00002). The duration of recurrent kidney stones was 174.7±148.6 and 163.3±129.5 months for cases and controls (p=0.738). The onset time of CKD was 61.1±35.4 months. Among cases, 93.5% were men, 77.4% were hypertensive, and 67.9% had dyslipidemia, significantly differing from the controls (see Table 1). There were no differences between cases and controls concerning the duration of recurrent kidney stones, type of health insurance, overweight status, hyperuricemia, diabetes mellitus, exercise habits, metabolic study alterations, history of renal colic, renal stone localization, number, and size. The difference was borderline for alcohol consumption and smoking habits. Multivariable logistic regression, incorporating variables with statistical significance (age, gender, hypertension, alcohol consumption, smoking habit) into the model, revealed that higher age corresponds to a greater risk of CKD (Odds ratio 1.052; 95% CI, 1.003 to 1.103). Furthermore, the male gender exhibited a 5.5 times higher likelihood of suffering from CKD (Odds ratio 5.5; 95% CI, 1.2 to 26.5). Conclusion In patients with recurrent kidney stones, higher age, and male gender were identified as factors associated with the development of CKD.

Urinary Tract Infection Predictors in Patients Undergoing Retrograde IntraRenal Surgery for Renal Stones: Does the Instrument Make the Difference?

Background: Retrograde intrarenal surgery (RIRS) using flexible ureterorenoscopes is a cornerstone approach for renal stone removal, yet it carries a significant risk of postoperative urinary tract infection (UTI). With the emergence of single-use ureterorenoscopes, there is growing interest in their potential to mitigate this risk. This study aimed to compare the postoperative infection rates between single-use and multi-use ureterorenoscopes in RIRS procedures and to identify predictors of postoperative UTI. Methods: Data were collected from 112 consecutive patients who underwent RIRS for renal stones between March 2022 and September 2023. Peri-operative variables including age, gender, body mass index (BMI), stone size, stone location, type of ureterorenoscope, Hounsfield Units (HU), pre-operative hydronephrosis, laboratory analysis, and operative time were evaluated. Univariate and multivariate logistic regression analyses were performed to assess the predictors of postoperative UTI. Results: Of the cohort, 77 surgeries (68.7%) utilized multi-use ureterorenoscopes, while 35 (31.3%) utilized single-use devices. Stone diameter, number of stones, type of ureterorenoscope, and operative time were significant predictors of postoperative UTI in the univariate analysis. Multivariable logistic regression showed that operative time (OR, 1.3; 95% CI, 0.55-0.99; p = 0.03) and type of ureterorenoscope (multi-use vs. single-use) (OR, 1.14; 95% CI, 1.08-1.2; p < 0.001) were independent predictors of postoperative UTI. Conclusions: In conclusion, this study highlights that multi-use ureterorenoscopes and prolonged operative time are associated with an increased risk of postoperative UTI in RIRS procedures. Careful pre-operative evaluation and meticulous patient selection are essential to minimize the occurrence of postoperative UTIs and optimize patient outcomes in RIRS for renal stones.

Success rate and complications of performing elective ureteroscopy in

The aim of this study was to compare the outcomes, success rate, and complications of performing elective ureteroscopy at different times: <1 week from renal colic initiation (early) and more than 1 week from renal colic initiation (late) in patients with ureteral stone larger than 6 mm. This comparative observational study was conducted on 338 consecutive patients. Patients were evaluated in two groups: patients who underwent ureteroscopy in <1 week (A) and patients who underwent ureteroscopy in more than 1 week (B) from renal colic initiation. Helical unenhanced computed tomography was used to assess the size, location, and hardness of stone for all patients. Operation success was defined as complete clearance of stone with no stone residue (stone free) at 2-week postoperative ultrasonography with no need to further interventions. Operation data were collected using medical records, and postoperative complications were investigated at 2 weeks postoperative follow-up visits. Group A included 165 patients and Group B included 173 patients. The overall mean stone size was 8.60 ± 1.12 mm: for Group A 9.13 ± 0.94 mm and for Group B 8.10 ± 1.04 mm (P < 0.001). Stone residues were found in 11 patients: 9 in Group A (5.4%) and 2 in Group B (1.1%) (P = 0.026). Nine patients needed repeated ureteroscopy: 8 (4.8%) in Group A and 1 (0.6%) in Group B (P = 0.015). A double-J stent was used for 85 (51.5%) patients in Group A and 66 (38.2%) patients in Group B (P = 0.016). Major intraoperative complications did not happen in any patients. Fifty-three (32.1%) patients in Group A and 28 (16.2%) patients in Group B suffered from postoperative complications (P = 0.001). Our study revealed that performing elective ureteroscopy with an interval of more than 1 week from the onset of renal colic in combination with medical treatments was associated with less need for double-J stent placement, less need for repeated ureteroscopy, and fewer postoperative complications compared to performing elective ureteroscopy in <1 week from the renal colic onset in nonemergent patients with ureteral stone larger than 6 mm. Although the rate of ureteroscopy failure was higher among the patients who underwent ureteroscopy in <1 week from their renal colic initiation, there was no statistically significant relationship between performing ureteroscopy in <1 week and an increased risk for ureteroscopy failure.