The effect of distal ureteral lateralization angle on ureteral trauma avoidance and successful ureteral access sheath placement.

BACKGROUND: The use of ureteral access sheaths (UAS), which offer advantages in flexible ureteroscopic lithotripsy (fURL), may lead to undesirable conditions such as ureteral injury, ischemia, and prolonged ureteral stenosis. The aim of this study was to investigate the effect of the distal ureteral lateralization angle on successful UAS placement. METHODS: We analyzed the data of patients who underwent fURL for kidney and/or proximal ureteral stones retrospectively. Based on the preoperative computed tomographic examinations of the patients, the bladder outlet was considered the zero point. We calculated the angle values between the horizontal axis passing through this point and the most lateralized point of the distal ureter. The patients were divided into two groups: those to whom UAS was successfully placed and those to whom UAS placement failed. RESULTS: No significant difference was detected between the groups with successful UAS placement (n=36) and those without UAS placement (n=12) in terms of sex, laterality, localization, number of stones, stone burden, and bladder volumes evaluated with preoperative computed tomography (p>0.05). However, a significant difference was found between the two groups regarding age and distal ureteral lateralization angle (p<0.001, p=0.013). CONCLUSION: The distal ureteral lateralization angle is considered to be an effective factor in the placement of UAS in patients scheduled for fURS.

Fabrication of acoustically and physically validated artificial stones to natural kidney stones under shock waves and laser lithotripsy.

To present an efficient method for fabricating artificial kidney stones with acoustic and physical properties to assess their fragmentation efficiency under shock waves and laser lithotripsy for very hard stones. The mixture ratio of super-hard plaster and water was adjusted to produce artificial kidney stones for comparison with > 95% human genuine calcium oxalate monohydrate (COM) and uric acid (UA) stones. Acoustic and physical properties, such as wave speed, stone hardness, density, compressive strength, and stone-free rates under shock-wave and laser lithotripsy, were assessed. The longitudinal wave speed of artificial stones prepared at a plaster-to-water ratio of 15:3 closely matched that of COM stones. Similarly, the transverse wave speed of artificial stones prepared at a plaster-to-water ratio of 15:3 to 15:5 aligned with that of COM stones. Stone fragmentation using shock-wave of artificial stones with mixed ratios ranging from 15:3 to 15:5 resembled that of COM stones. The Vickers hardness was similar to that of artificial stones produced with a mixing ratio of 15:3, similar to that of COM stones, while that of artificial stones produced with a mixing ratio of 15:5 was similar to that of UA stones. Density-wise, artificial stones with mixing ratios of 15:4 and 15:5 resembled COM stones. Compressive strength test results did not confirm the similarity between natural and artificial stones. The stone fragmentation using laser showed that stones produced with higher moisture content at a mixing ratio of 15:6 were similar to COM stones. This novel method for fabricating artificial kidney stones could be used to provide reliable materials for lithotripsy research.

Optimizing the outcome of non-pre-stented flexible ureteroscopic lithotripsy regarding the quality of life, when to remove the stent?

OBJECTIVES: To investigate the safety of short-term stenting following flexible ureteroscopic lithotripsy (fURL) for patients without preoperative stents. Retaining double-J stent for 1-2 weeks after fURL is a common practice. At present, data on short-term stenting after non-pre-stented fURL is still lacking. METHODS: 182 patients who met inclusion criteria were retrospectively divided into the 2-days group (2-day removal, 76 cases) and the 1-week group (1-week removal, 106 cases). The study endpoint was stent-associated adverse symptoms assessed by follow-up and completed validated questionnaires on postoperative days (POD) 7 and 12. A postoperative imaging review was performed 1 month after the surgery. RESULTS: No statistical differences were found in the patients' demographic and stone-related characteristics. The 2-days group showed fewer urinary tract symptoms and lower scores on the ureteral stent symptom questionnaire on POD 7: less backache during urination (p = 0.004), less hematuria (p = 0.031), less frequent urination (p = 0.004), lower urinary symptoms index (p < 0.001), lower general health index (p < 0.001), and lower performance index (p < 0.001). There were no significant differences in fever (p = 0.372), visual analogue scale score (p = 0.760), and painkiller requirements (p = 0.160) on POD 7. The average general health score and work performance score remained significantly higher in the 1-week group patients at 5 days after removal compared to the 2-days group patients at 5 days after removal. (p < 0.001, p = 0.005). Five patients in the 2-days group and 15 patients in the 1-week group returned to the emergency department for additional treatments. No patient required rehospitalization. Stone-free rates were 85.5% in the 2-days group and 80.2% in the 1-week group (p = 0.499), respectively, and none of the patients got aggravating hydronephrosis. CONCLUSIONS: Compared to the common 1-week stent removal option, short-term stenting after non-pre-stented fURL is safe, which can enhance the patient's quality of life.

Postoperative Renal Abscess Following Tip-Flexible Suctioning Ureteral Access Sheath and Digital Ureteroscopic Lithotripsy: A Case Report.

BACKGROUND The tip-flexible suctioning ureteral access sheath (TFS-UAS) can be bent under flexible ureteroscopes, which facilitates removal of renal stone segments by irrigation and suctioning effects. Small-scale comparative studies found it safer and more efficacious than traditional UAS. However, complications such as renal abscess were not documented after TFS-UAS combined with digital FURS. CASE REPORT A 57-year-old woman had right lumbar pain that persisted for 1 year. A plain computed tomography (CT) scan revealed multiple renal pelvicalyceal stones (maximum diameter 20×9 mm). She was admitted to undergo elective surgery with a TFS-UAS combined with digital flexible ureteroscopic lithotripsy. The operation was deemed successful and she was given postoperative antibiotics for 2 days before discharge. Eight postoperative days later, she was admitted to the emergency department due to high fever (39.6°C). Plain CT revealed intact double-J stents and no abnormalities. She was readmitted to the urological department to receive antibiotic therapy, which progressed to septic shock (blood pressure 80/50 mmHg) and required immediate transfer to the intensive care unit. Contrast-enhanced CT revealed a right renal abscess. She was promptly resuscitated and given stronger antibiotics. She recovered well and was discharged with 2-week oral levofloxacin treatment. Follow-up ultrasound found no renal abscess. CONCLUSIONS While TFS-UAS with digital FURs is an effective approach for multiple renal stones, there is a risk of postoperative renal abscess, possibly due to altered intrarenal pressure.

Retrospective Analysis of Risk Factors for Urinary Tract Infection after Ureteral Calculi Surgery.

BACKGROUND: Ureteral calculi are a common diagnosis in the field of urology worldwide, and they represent a prevalent subtype of urolithiasis. Ureteroscopic stone surgery is the cornerstone treatment, but postoperative urinary tract infection (UTI) remains a clinical concern. Our study aims to analyse specific risk factors associated with postoperative UTIs following ureteroscopic stone surgery. METHODS: We conducted a case-control study and collected clinical data from 145 patients who underwent ureteroscopic lithotripsy at our hospital from January 2021 to January 2023. Binary logistic regression analysis was used to investigate risk factors for postoperative UTI. Receiver operating characteristic curves were plotted, and area under the curve (AUC) was calculated to evaluate the predictive value of each factor. RESULTS: Forty patients developed UTI after ureteroscopic stone surgery. Compared with the control group, the case group showed significant differences in stone size, history of diabetes mellitus and preoperative urine culture results (p < 0.05). Multivariable binary logistic regression analysis revealed that stone size (Odds Ratio (OR) = 1.952, p = 0.010), history of diabetes mellitus (OR = 2.438, p = 0.038) and preoperative urine culture (OR = 2.914, p = 0.009) were independent risk factors for postoperative UTI. The AUC values of stone size, history of diabetes mellitus and preoperative urine culture were 0.680, 0.627 and 0.630, respectively. The AUC of the combined prediction was 0.756. CONCLUSIONS: This study identified risk factors for postoperative UTI following ureteroscopic stone surgery and emphasised the importance of stone size, history of diabetes mellitus and preoperative urine culture in the diagnosis.

Application of 11/13Fr suctioning ureteral access sheath and 8.55Fr single-use digital flexible ureteroscope in one-stage flexible ureteroscopic lithotripsy: an initial experience of 900 cases.

OBJECTIVES: To report our initial experience of one-stage flexible ureteroscopic lithotripsy(FURL) with 11/13Fr suctioning ureteral access sheath(UAS) and 8.55Fr single-use digital flexible ureteroscope(SDFU) in upper ureteral or renal calculi. MATERIALS AND METHODS: We retrospectively collected the clinical data of 900 adult patients with upper ureteral or renal calculi treated by FURL with 11/13Fr suctioning UAS and 8.55Fr SDFU from January 2022 to April 2024. Demographics, peri- and postoperative outcomes were assessed. RESULTS: In all, 40 of 940 cases(4.26%) failed to introduce UAS and required second-stage FURL because of ureterostenosis and were excluded. Mean stones size of the remaining 900 eligible cases was 1.68 ± 0.58 cm in greatest diameter. There were 228 cases of upper ureteral stone, 456 cases of renal stone and 216 cases of concomitant ureteral and renal calculi. The mean operation time was 52.20 ± 20.21 min and the postoperative hospital stay was 2.87 ± 1.37 days. The stone-free rate of 1 month postoperatively was 89.56% and only 2.44% of patients with residue underwent additional reoperation. The rate of postoperative fever, postoperative pain needing analgesic and slight ureteral mucosal injury were 5.11%, 8.22% and 7.78%, respectively. None of patient suffered from severe complications, such as sepsis or ureteral perforation. CONCLUSION: It's practical and suitable for the vast majority of adult patients to undergo FURL in single session with 11/13Fr suctioning UAS without preoperative stenting. FURL with 11/13Fr suctioning UAS and 8.55Fr SDFU is feasible, reliable, safe, and efficient in the management of renal stone and upper ureteral stone.

Initial Clinical Experience With a Novel Robotically Assisted Platform for Combined Mini-Percutaneous Nephrolithotomy and Flexible Ureteroscopic Lithotripsy.

PURPOSE: We sought to evaluate the technical feasibility of performing a combined robotically assisted mini-percutaneous nephrolithotomy (PCNL) and flexible ureteroscopy (URS) procedure by a single urologist using the MONARCH Platform, Urology (Johnson & Johnson MedTech, Redwood City, California). MATERIAL AND METHODS: In this prospective, first-in-human clinical trial, 13 patients underwent robotically-assisted PCNL for renal calculi at the University of California-Irvine, Department of Urology. Successful completion of the procedure was assessed as the primary endpoint. Postoperative adverse events were monitored for 30 days following the completion of the procedure. Stone ablation efficiency was evaluated on postoperative day 30 with low-dose 2-3 mm slice CT scans. Patients were classified according to the maximum length of their residual stone fragments as either absolute stone-free (Grade A), < 2 mm remnants (Grade B), or 2.1-4.0 mm remnants (Grade C). RESULTS: The combined robotic mini-PCNL and URS procedure was successfully completed in 12 of 13 procedures. No robotic device-related adverse events occurred. Preoperative stone burden was quantified by both maximum linear measurement (median 32.8 mm) as well as by CT-based volume (median 1645.9 mm3). Using the unique robotically assisted targeting system, percutaneous access was gained directly through the center of the renal papilla in a single pass in all cases. Median operative time was 187 minutes (range: 83-383 minutes). On postoperative day 30, a 98.7% (range: 72.9%-100.0%) volume reduction was achieved, with 5 Grade A (38.5%), 1 Grade B (7.7%), and 2 Grade C (15.4%). Three patients experienced complications (2 grade 1 and one grade 2 Clavien-Dindo). CONCLUSIONS: Our preliminary investigation demonstrates the safety, efficacy, and feasibility of a unique robotic-assisted combined mini-PCNL and URS platform.

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

BACKGROUND: 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). AIM: To study one-step PTCSL using the percutaneous transhepatic one-step biliary fistulation (PTOBF) technique guided by three-dimensional (3D) visualization. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Using ensemble learning and hierarchical strategy to predict the outcomes of ESWL for upper ureteral stone treatment.

Urinary tract stones are a common and frequently recurring medical issue. Accurately predicting the success rate after surgery can help avoid ineffective medical procedures and reduce unnecessary healthcare costs. This study collected data from patients with upper ureter stones who underwent extracorporeal shock wave lithotripsy, including cases of successful as well as unsuccessful stone removal after the first and second lithotripsy procedures, and constructed prediction systems for the outcomes of the first and second lithotripsy procedures. Features were extracted from three categories of information: patient characteristics, stone characteristics, and extracorporeal shock wave lithotripsy machine data, and additional features were created using Feature Creation. Finally, the impact of features on the models was analyzed using six methods to calculate feature importance. Our prediction model for the first lithotripsy, selected from among 43 methods and seven ensemble learning techniques, achieves an AUC of 0.91. For the second lithotripsy, the AUC reaches 0.76. The results indicate that the detailed and binary information provided by patients regarding their history of stone experiences contributes differently to the predictive accuracy of the first and second lithotripsy procedures. The prediction tool is available at https://predictor.isu.edu.tw/ks.

Contemporary Trends and Outcomes of Intravascular Lithotripsy in Percutaneous Coronary Intervention: Insights From BMC2.

BACKGROUND: With an aging population and an increase in the comorbidity burden of patients undergoing percutaneous coronary intervention (PCI), the management of coronary calcification for optimal PCI is critical in contemporary practice. OBJECTIVES: This study sought to examine the trends and outcomes of coronary intravascular lithotripsy (IVL), rotational/orbital atherectomy, or both among patients who underwent PCI in Michigan. METHODS: We included all PCIs between January 1, 2021, and June 30, 2022, performed at 48 Michigan hospitals. Outcomes included in-hospital major adverse cardiac events (MACEs) and procedural success. RESULTS: IVL was used in 1,090 patients (2.57%), atherectomy was used in 1,743 (4.10%) patients, and both were used in 240 patients (0.57% of all PCIs). IVL use increased from 0.04% of PCI cases in January 2021 to 4.28% of cases in June 2022, ultimately exceeding the rate of atherectomy use. The rate of MACEs (4.3% vs 5.4%; P = 0.23) and procedural success (89.4% vs 89.1%; P = 0.88) were similar among patients treated with IVL compared with atherectomy, respectively. Only 15.6% of patients treated with IVL in contemporary practice were similar to the population enrolled in the pivotal IVL trials. Among such patients (n = 169), the rate of MACEs (0.0%) and procedural success (94.7%) were similar to the outcomes reported in the pivotal IVL trials. CONCLUSIONS: Since its introduction in February 2021, coronary IVL use has steadily increased, exceeding atherectomy use in Michigan by February 2022. Contemporary use of IVL and atherectomy is generally associated with high rates of procedural success and low rates of complications.

A comparative study of shockwave intravascular lithotripsy and conventional percutaneous coronary intervention in the treatment of severe coronary artery calcification lesions.

BACKGROUND: The purpose of this study was to evaluate the effectiveness of intravascular lithotripsy (IVL) in the treatment of severe coronary artery calcification (CAC) lesions. METHODS: In this study, we selected patients diagnosed with severe CAC lesions confirmed by coronary angiography (CAG) who were hospitalized in Yulin First People's Hospital between December 2021 and December 2022 and required percutaneous coronary intervention (PCI). Using a random number table, we divided all patients into the IVL group and the PCI group in the order of interventional therapy. We compared both groups in terms of the surgical success rate, intraoperative manipulation characteristics, procedural complication, and cumulative incidence of major adverse cardiovascular events (MACE). RESULTS: (1) There were no differences in the surgical success rate, incidence of MACE, and occurrence of procedural complication between the two groups; (2) Compared with the conventional PCI group, patients in the IVL group used fewer predilatation balloons, and the difference was statistically significant (all P < 0.05); (3) Compared with the conventional PCI group, patients in the IVL group had lesser surgery time and lesser radiation time, with lesser proportion of patients who were assisted with stent implantation using coronary artery rotational atherectomy, and this difference was statistically significant (P < 0.05); (4) The mean stent diameter and length in the IVL group was greater than those in the conventional PCI group but the difference was not statistically significant (P > 0.05). CONCLUSION: In this study, we found that IVL was a highly safe and effective procedure in the treatment of severe CAC lesions that did not increase the surgery and radiation time, and it could also reduce the use of predilatation balloons, thus improving the management of CAC lesions. Thus, IVL can be a novel choice in treating severe CAC lesions.

Verification of surgical factors affecting the efficiency of stone extraction with one-surgeon basketing technique using a f-URSL simulation model.

PURPOSE: Stone extraction is an important treatment option when performing flexible ureteroscopic lithotripsy (f-URSL) for upper urinary stones. We used a f-URSL simulator model to investigate surgical factors affecting the efficacy of stone extraction with the one-surgeon basketing technique. MATERIALS AND METHODS: This simulator-based study involved eight urologists and eight residents. These participants each performed two tasks, with Flexor (Cook Medical) and Navigator (Boston Scientific) ureteral access sheaths, with and without the M-arm (MC Medical) single-use basket holder, and with models representing both left and right kidneys. The two tasks were to touch each renal calix with the ureteroscope, and to extract stones. As outcomes, we recorded the number of times that the ureteroscope became stuck during insertion, the number of times a stone was dropped during removal, the number of times the basket forceps were opened and closed, and the time required to accomplish each task. RESULTS: The ureteroscope became stuck significantly more often when Navigator was used compared with Flexor overall, and for both urologists and residents (all p<0.01). Stones were dropped significantly more often on the ipsilateral side (kidney on the same side as the operator's hand) than on the contralateral side overall (p=0.01), and the basket forceps were opened and closed significantly more often on the ipsilateral side than on the contralateral side both overall and by residents (all p<0.01). CONCLUSIONS: The efficiency of stone extraction during f-URSL with the one-surgeon basketing technique was affected by differences in ureteral access sheath and the kidney side.

[Progress in Surgical Treatment of Upper Urinary Tract Stones in Children].

The incidence of urinary calculi in children has been increasing annually,and most of the cases are upper urinary tract stones.At present,surgery is the main way to treat upper urinary tract stones in children.With the gradual development of minimally invasive techniques in surgery,percutaneous nephrolithotomy,retrograde intrarenal surgery,and extracorporeal shock wave lithotripsy have become the main methods for treating upper urinary tract stones in children.We reviewed the current progress in surgical treatment of upper urinary tract stones in children and provided prospects for future treatment options.