Outcomes and Costs Following Mini-percutaneous Nephrolithotomy or Flexible Ureteroscopic Lithotripsy for 1-2-cm Renal Stones: Data From a Prospective, Randomized Clinical Trial

PURPOSE

We evaluate the outcomes of ureteroscopy vs prone mini-percutaneous nephrolithotomy for 1-2-cm renal stones using a 2-group parallel randomized control trial.

MATERIALS AND METHODS

Adult patients presenting with renal stones between 1 and 2 cm were randomized. Exclusion criteria included solitary kidney, multiple stones, and comorbidities precluding prone positioning. Block randomization was performed and was opened to the surgeon the morning of the procedure. Stone-free rate was evaluated by computed tomography 1-30 days postoperatively. Complications, re-treatment rates, and costs were evaluated.

RESULTS

A total of 51 mini-percutaneous nephrolithotomy and 50 ureteroscopy patients were included. Baseline demographics were similar. Using a 2-mm cutoff, stone-free rate was higher in the mini-percutaneous nephrolithotomy group (76 vs 46%, P = .0023). The residual stone burden was significantly higher in the ureteroscopy group than the mini-percutaneous nephrolithotomy group (3.6 vs 1.4 mm, P = .0026). Fluoroscopy time was significantly higher in the mini-percutaneous nephrolithotomy group (273 vs 49 seconds, P < .0001). There were no differences in postoperative complications within 30 days, the necessity of a secondary procedure within 30 days, and pre- to postoperative creatinine change (P > .05). Surgical time did not vary significantly (P = .1788). Average length of stay was higher in the mini-percutaneous nephrolithotomy group (P < .0001). Both net revenue and direct costs were higher in mini-percutaneous nephrolithotomy procedures (P < .05), though they offset each other with a nonsignificant operating margin (P = .2541).

CONCLUSIONS

In a prospective, randomized, controlled clinical trial using a 2-mm residual stone burden cutoff, mini-percutaneous nephrolithotomy was more likely to render patients stone-free than flexible ureteroscopy. Complications, surgical times, and operating margins did not vary between the approaches.

Acute Pancreatitis following Percutaneous Electrohydraulic Lithotripsy

The gold-standard treatment of acute calculous cholecystitis is cholecystectomy. For patients not suitable for surgery, endoscopic or percutaneous techniques can be used for gallbladder decompression. The national percutaneous cholecystostomy rates have increased by 567% from 1994 to 2009*. Some of these patients are still not surgical candidates after the acute cholecystitis episode has resolved. Hence, it is crucial to have a management plan in place for such patients. There are several peroral endoscopic treatment options available, including ultrasound-guided transmural drainage, lithotripsy, and transpapillary stenting**. Furthermore, due to the advent of percutaneous biliary endoscopes, interventional radiology (IR) can now perform percutaneous lithotripsy and gallstone removal followed by cystic duct stenting. This method aims to internalize gallbladder drainage without the need for a long-term external cholecystostomy tube. Acute pancreatitis is a rare complication that can arise following interventions involving the biliary and cystic ducts. Acute pancreatitis can occur after retrograde ampullary manipulation during endoscopic retrograde cholangiopancreatography. However, this can sometimes happen after percutaneous antegrade interventions performed by IR. In this report, we will examine a rare complication that occurred in a patient with acute calculous cholecystitis: acute pancreatitis following percutaneous electrohydraulic lithotripsy with cystic duct stenting performed by IR.

Ureteral Stent Placement Prior to Definitive Stone Treatment Is Associated With Higher Postoperative Emergency Department Visits and Opioid Prescriptions for Youth Having Ureteroscopy or Shock Wave Lithotripsy

PURPOSE

Little is known about the impact of ureteral stents on youth having stone surgery. We evaluated the association of ureteral stent placement before or concurrent with ureteroscopy and shock wave lithotripsy with emergency department visits and opioid prescriptions among pediatric patients.

MATERIALS AND METHODS

We conducted a retrospective cohort study of individuals aged 0-24 years who underwent ureteroscopy or shock wave lithotripsy from 2009-2021 at 6 hospitals in PEDSnet, a research network that aggregates electronic health record data from children's health systems in the United States. The exposure, primary ureteral stent placement, was defined as a stent placed concurrent with or within 60 days before ureteroscopy or shock wave lithotripsy. Associations between primary stent placement and stone-related ED visits and opioid prescriptions within 120 days of the index procedure were evaluated with mixed-effects Poisson regression.

RESULTS

Two-thousand ninety-three patients (60% female; median age 15 years, IQR 11-17) had 2,477 surgical episodes; 2,144 were ureteroscopy and 333 were shock wave lithotripsy. Primary stents were placed in 1,698 (79%) ureteroscopy episodes and 33 (10%) shock wave lithotripsy episodes. Ureteral stents were associated with a 33% higher rate of emergency department visits (IRR 1.33; 95% CI 1.02-1.73) and a 30% higher rate of opioid prescriptions (IRR 1.30; 95% CI 1.10-1.53). The magnitudes of both associations were greater for shock wave lithotripsy. Results were similar for age <18 and were lost when restricted to concurrent stent placement.

CONCLUSIONS

Primary ureteral stent placement was associated with more frequent emergency department visits and opioid prescriptions, driven by pre-stenting. These results support elucidating situations where stents are not necessary for youth with nephrolithiasis.

Ex-vivo ureteroscopy, laser lithotripsy, and stone basketing extraction of deceased donor kidney stones during machine perfusion preservation

The incidence of nephrolithiasis in kidney donors is rare. The timing and treatment of nephrolithiasis in deceased donor kidneys are not well established. While some programs have proposed ex-situ rigid or flexible ureteroscopy treatment before transplantation, we report on two cases of kidney stones in the same deceased donor that we treated by flexible ureteroscopy and laser lithotripsy performed during the storage time on a hypothermic perfusion machine. Two deceased donor kidneys were found to have multiple kidney stones discovered on preprocurement CT imaging. The right kidney had less than five 2-3 mm stones, whereas the left had five to ten 1 mm stones with a single 7 mm stone. Both organs were placed on a hypothermic perfusion machine and maintained at a temperature of 4°C. An ex-vivo flexible ureteroscopy with laser lithotripsy and basket extraction was performed while the kidneys were maintained on Lifeport* perfusion machine. The cold ischemia time was 16.9 and 23.1 h. After 12 months of observational follow-up, neither recipient had nephrolithiasis, UTI, or other urologic complications. The creatinine values now are 1.17 and 2.44 mg/dL (103.4 and 215.7 μmol/L), respectively. Ex-vivo flexible ureteroscopy with laser lithotripsy and stone removal on machine-perfused kidneys appears to be safe and offers a good option to treat graft nephrolithiasis and prevent posttransplant complications. Ureteroscopy serves as a minimally invasive treatment option with direct stone removal. Performing this while on machine perfusion minimizes the ischemic time of the kidney and resultant complications or delays in graft function.

Surgical Stone Treatment: Patterns May Predict Performance on Episode Based Cost Measure in the Quality Payment Program

INTRODUCTION

The Renal or Ureteral Stone Surgical Treatment Episode based Measure in the Quality Payment Program (QPP) evaluates clinicians' cost to Medicare for beneficiaries who receive surgical treatment for stones.¹ The measure score is calculated from Medicare claims according to a complex methodology.² This paper seeks to describe the stone treatment patterns of urologists and establish benchmarks for 2 surrogate measures- preoperative stenting and postoperative infection-which may predict clinician performance on the episode cost based measure.

METHODS

The study data were drawn from the adjudicated claims of 960 providers who performed at least 30 surgical stone treatments between January 1, 2020 and June 30, 2022. To allow for the correlation of procedures performed by same providers, generalized estimating equations logistic regression models were used to evaluate the rate of preoperative stenting and postoperative infection.

RESULTS

185,076 surgical episodes (113,799 [61.5%] ureteroscopy, 63,931 [34.5%] extracorporeal shock wave lithotripsy (ESWL), and 7,346 [4.0%] percutaneous nephrolithotripsy (PCNL)) were identified over the study period. Preoperative stenting was performed in 35,550 episodes (19.2%) and postoperative infection was documented in 13,114 episodes (7.1%). Preoperative stenting and postoperative infection were significantly more common in patients who were female (aOR 1.42, 1.38), in those undergoing ureteroscopy vs ESWL (aOR 3.24, 1.66), and in patients on Medicare vs Commercial insurance (aOR 1.19, 1.17).

CONCLUSIONS

This large study of surgical stone treatments documents rates of events and associated attributes of patients that may increase episode cost and be relevant to urologists participating in the QPP.

Endoscopic therapy for Bouveret syndrome, illustrated by a case report

Bouveret syndrome is an exceptionally rare form of gallstone ileus secondary to a bilioenteric fistula, through which a voluminous gallstone can migrate into the pylorus or duodenum, thereby causing gastric outlet obstruction. In order to increase awareness, we reviewed the clinical features, diagnostic tools and management options for this uncommon entity. We specifically focus on endoscopic therapeutic options, illustrated by a case of a 73 year old woman with Bouveret syndrome, where endoscopic electrohydraulic lithotripsy was successful in relieving gastroduodenal obstruction.

Gallbladder perforation following peroral cholangioscopy-guided lithotripsy: A case report

Peroral cholangioscopy-guided lithotripsy is highly effective in clearing difficult bile duct stones. It can cause adverse events, such as cholangitis and pancreatitis; however, gallbladder perforation is extremely rare. Herein, we describe the case of a 77-year-old woman who developed gallbladder perforation following peroral cholangioscopy -guided lithotripsy. She was referred to our hospital to treat multiple large bile duct stones. She underwent peroral cholangioscopy-guided lithotripsy because of conventional lithotripsy failure. After a cholangioscope was advanced into the bile duct, saline irrigation was used for visualization. Electronic hydraulic lithotripsy was performed, but it took time for fragmentation because the calculus was hard. The 2-h endoscopic procedure did not completely remove the stone, and treatment was discontinued after placing a biliary plastic stent and nasobiliary tube. After the endoscopic procedure, she started experiencing right hypochondrial pain, which worsened the next day. Computed tomography showed a gallbladder wall defect in the gallbladder fundus with pericholecystic fluid. She was diagnosed with gallbladder perforation and underwent emergency surgery. A perforation site was found at the gallbladder fundus. Open cholecystectomy, choledochotomy, and extraction of residual bile duct stones were performed. The patient was discharged 9 days post-surgery without any complications. The saline irrigation used for visualization may have caused a surge in intra-gallbladder pressure, resulting in gallbladder perforation. Therefore, endoscopists may need to conserve irrigation water during peroral cholangioscopy-guided lithotripsy.

Evaluation of ureteral injuries caused by ureteral access sheath insertion during ureteroscopic lithotripsy

OBJECTIVE

To evaluate ureteral injuries caused by insertion of a 13-Fr ureteral access sheath and identify factors (other than pre-stenting) that are predictive of ureteral injury.

METHODS

We enrolled 201 patients who underwent ureteroscopic lithotripsy (URSL). We excluded 80 patients who underwent ureteral stent insertion before URSL, 10 patients who did not use a ureteral access sheath, and 2 patients in whom a ureteral access sheath could not be inserted. In total, 109 patients were analyzed; all underwent insertion of a 13-Fr ureteral access sheath. We investigated ureteral injuries using the Traxer ureteral injury scale.

RESULTS

There were 21 (19.3%) cases of ureteral access sheath-related ureteral injury, including 11 (10.1%) grade 2 cases and 10 (9.2%) grade 3 cases. The ureteral injury location was the proximal ureter in 20 cases (18.3%), middle ureter in one case (0.9%), and distal ureter in zero cases. Multiple logistic regression analysis showed that male sex and smaller stone diameter were significant predictive factors for ureteral injury (p = 0.037, odds ratio [OR]: 5.19, 95% confidence interval [CI]: 1.11-24.3 and p = 0.02, OR: 0.83, 95% CI: 0.71-0.97, respectively). Postoperative ureteral stricture did not occur in any cases.

CONCLUSIONS

The rate of ureteral injury caused by a 13-Fr ureteral access sheath was considerable, and most ureteral injuries occurred in the proximal ureter. Male sex and smaller stone diameter were significant predictive factors for ureteral injury. The proximal ureter should be confirmed when using a 13-Fr ureteral access sheath, particularly in male patients and patients with small stones.

Intravascular Lithotripsy and Drug-Coated Balloon Angioplasty for Severely Calcified Common Femoral Artery Atherosclerotic Disease

OBJECTIVES

Intravascular lithotripsy (IVL) followed by drug-coated balloon (DCB) angioplasty might be a valuable alternative to surgery for calcified common femoral artery (CFA) atherosclerotic disease. Nonetheless, the 12 months performance of this treatment strategy remains unknown. This study reports on the 12 months outcomes of IVL with adjunctive DCB angioplasty for calcified CFA lesions.

METHODS

This is a retrospective single-center, single-arm study. Consecutive patients treated by IVL and DCB for calcified CFA disease between February 2017 and September 2020 were evaluated. The primary measure outcome of this analysis was primary patency. Procedural technical success (<30% stenosis), freedom from target lesion revascularization (TLR), secondary patency, and overall mortality were additionally analyzed.

RESULTS

Thirty-three (n=33) patients were included in this study. The majority presented with lifestyle limiting claudication (n=20, 61%), 52% (n=17) of the patients had chronic kidney disease (CKD) and 33% (n=11) had diabetes. The procedural technical success was 97% (n=32). A flow-limiting dissection post IVL was observed in 2 patients (6%) and a peripheral embolization in a single patient (3%), while the bail-out stenting rate amounted to 12% (n=4). No perforation was observed. The median length of hospital stay was 2 days (interquartile range 2-3). At 12 months, the primary patency was 72%. The freedom from TLR and the secondary patency rates were 94% and 88%, respectively. The 12-month survival amounted to 100% and 75% (n=25) of the patients were asymptomatic or presented with mild claudication. The presence of chronic limb-threatening ischemia (CLTI) (hazard ratio [HR], 0.92; confidence interval (CI); 0.18-4.8, p=0.7) or CKD (HR, 1.30; 95% CI, 0.29-5.8; p=0.72), as well as the use of a 7 mm IVL catheter (HR, 0.59; 95% CI, 0.13-2.63; p=0.49) or of high-dose DCB (HR, 0.68; 95% CI, 0.13-3.53; p=0.65) did not influence the primary patency.

CONCLUSIONS

In this study, the combination of IVL and DCB angioplasty for calcified CFA disease was associated with low risk for periprocedural complications, acceptable 12 months clinical outcomes, and low rates of reinterventions.

CLINICAL IMPACT

Intravascular lithotripsy in combination with DCB angioplasty can be an alternative to surgery in highly selected patients with CFA atherosclerotic disease. In this Cohort the combination therapy lead to acceptable clinical results and low reintervention rates at 12 months.

Displacement of Lower Pole Stones During Retrograde Intrarenal Surgery Improves Stone-free Status: A Prospective Randomized Controlled Trial

PURPOSE

Lower pole renal stones are associated with the lowest stone-free status of any location in the urinary tract during retrograde intrarenal surgery. Prior work has suggested displacing lower pole stones to a more accessible part of the kidney to improve stone-free status. We sought to prospectively compare the efficacy of laser lithotripsy in situ vs after displacement during retrograde intrarenal surgery for lower pole stones.

MATERIALS AND METHODS

Between July 2017 and May 2022 patients undergoing retrograde intrarenal surgery for lower pole stones were randomized into an in situ or displacement group. Demographics, comorbidities, and operative parameters were documented. Primary outcome was stone-free status, determined by combination of abdominal x-ray and renal ultrasound at 30-day follow-up. Secondary outcomes included operative time, 30-day complications, emergency department visits, and readmissions.

RESULTS

A total of 138 patients (69 per group) were enrolled and analyzed. Baseline characteristics were similar between groups. Stone-free status significantly favored the displacement group over the in situ group (95% vs 74%, P = .003, n=62 in each group). Operative time, total laser energy usage, 30-day complications, and 30-day emergency department visits or hospital readmissions were similar between groups. On multivariate analysis only study group allocation was significantly associated with stone-free status (P = .024).

CONCLUSIONS

Basket displacement of lower pole stones results in a significantly higher stone-free status compared to in situ lithotripsy. The technique is simple, atraumatic, and requires no additional equipment costs and little additional operative time, making it a practical tool in the treatment of lower pole stones.

Intravascular Lithotripsy and Drug-Coated Balloon Angioplasty for Severely Calcified Femoropopliteal Arterial Disease

INTRODUCTION

The combination of intravascular lithotripsy (IVL) and drug-coated balloon (DCB) angioplasty for calcified peripheral lesions is associated with promising short-term results. However, data regarding the 12 months performance of this treatment option is missing. This study reports on the outcomes of IVL and DCB angioplasty for calcified femoropopliteal disease.

METHODS

Patients treated with IVL and DCB for calcified femoropopliteal lesions between February 2017 and September 2020 were included into this study. The primary outcome measure of this analysis was primary patency. Secondary patency, freedom from target lesion revascularization (TLR) and overall mortality were additionally analyzed.

RESULTS

Fifty-five (n = 55) patients and 71 lesions were analyzed. Most patients presented with long-term limb-threatening ischemia (n = 31, 56%), 47% (n = 26) were diabetics, and 66% (n = 36) had long-term kidney disease. The median lesion length was 77 mm (interquartile range: 45-136), and 20% (n = 14) of the lesions were chronic total occlusions (CTOs). Eccentric calcification was found in 23% of the vessels (n = 16), and circumferential calcium (peripheral arterial calcium scoring system [PACSS] Class 3 and 4) was present in 78% (n = 55) of the treated lesions.The technical success after IVL amounted to 87% (n = 62) and the procedural success to 97% (n = 69). A flow-limiting dissection was observed in 2 cases (3%). Both the rates of target lesion perforation and distal embolization were 1% (n = 1). A bail-out scaffold was deployed in 5 lesions (7%). At 12 months the Kaplan-Meier estimate of primary patency was 81%, the freedom from TLR was 92% and the secondary patency 98%. The overall survival amounted to 89%, while the freedom from major amputation to 98%. The presence of eccentric disease, CTOs, or PACSS Class 4 did not increase the risk for loss of patency or TLR.

CONCLUSIONS

In this challenging cohort of patients, the use of IVL and DCB for calcified femoropopliteal lesions was associated with promising 12 months outcomes and an excellent safety profile.

Endoscopic Treatment of Acute Cholelithiasis Using AXIOS Stenting and Lithotripsy: A Case Series

The management of gallbladder diseases, including acute cholecystitis and choledocholithiasis, puts a significant strain on healthcare. The first-line treatment for acute cholecystitis is cholecystectomy. Patients who have concomitant choledocholithiasis, large stones, and/or gallstone pancreatitis may also benefit from endoscopic interventions. Endoscopic treatments may also be utilized in patients who are not surgical candidates due to underlying comorbidities. Studies examining the role of endoscopic lithotripsy in concomitant cholecystitis are limited. Herein we present a case series in which an AXIOS stent (Boston Scientific, Marlborough, Massachusetts) was placed into the gallbladder for decompression and utilized to access the gallbladder lumen to perform electrohydraulic lithotripsy in two patients.

Bowel Perforation after Extracorporeal Wave Lithotripsy: A Review of the Literature

INTRODUCTION

Extracorporeal wave lithotripsy (ESWL) is considered a first-line treatment for renal and ureteral stones up to 10-20 mm in diameter. Complications are uncommon, with a reported rate of 0-6% in the literature. Bowel perforation has only been described in a few case reports but requires rapid diagnosis and treatment.

METHODS

A review of the literature from PubMed/Medline, Embase, Cochrane, and Web of Science databases was performed including studies reporting bowel perforation secondary to ESWL between January 1990 and June 2022.

RESULTS

We found 16 case reports of intestinal perforation in the literature. Although some patients had previously undergone abdominal surgery or had inflammatory intestinal disease, others were without comorbidities that could lead to complications. Abdominal pain was the main symptom and imaging was required to confirm the diagnosis, which usually necessitated a surgical intervention. As regards the ESWL technique, it appears that the combination of a high energy level and the prone position constitutes a risk factor for these rare complications. At the authors' centre, only one case has been reported among 24,000 ESWL procedures over 20 years: A 59-year-old female who underwent ESWL for a distal right ureteral stone presented acute abdominal pain and free intraperitoneal pelvic fluid on ultrasound. A CT scan revealed a small bowel perforation requiring open laparotomy with primary closure.

CONCLUSIONS

In conclusion, although bowel perforation after ESWL is rare, progressive abdominal pain with tenderness at physical examination requires proper imaging evaluation to exclude bowel perforation and prompt intervention if required.

Shockwaves delivery for aortic valve therapy-Realistic perspective for clinical translation?

Calcific aortic valve disease (CAVD) is the most frequent valvular heart disorder, and the one with the highest impact and burden in the elderly population. While the quality and standardization of the current aortic valve replacements has reached unprecedented levels with the commercialization of minimally-invasive implants and the design of procedures for valve repair, the need of supplementary therapies able to block or retard the course of the pathology before patients need the intervention is still awaited. In this contribution, we will discuss the emerging opportunity to set up devices to mechanically rupture the calcium deposits accumulating in the aortic valve and restore, at least in part, the pliability and the mechanical function of the calcified leaflets. Starting from the evidences gained by mechanical decalcification of coronary arteries in interventional cardiology procedures, a practice already in the clinical setting, we will discuss the advantages and the potential drawbacks of valve lithotripsy devices and their potential applicability in the clinical scenario.

Current state of mobile health apps in endourology: a review of mobile platforms in marketplaces and literature

Several mobile healthcare (mHealth) apps are available in various marketplaces, but there is still concern about their accuracy, data safety, and regulation. The goal of this review was to critically analyze the mobile apps created for education, diagnosis, and medical and surgical treatment of patients with kidney stone disease (KSD), as well as to assess the level of data security, the contribution of physicians in their development and adherence to the Food and Drug Administration (FDA) and Medical Device Regulation (MDR) guidance. A comprehensive literature search was performed using PubMed (September 2022), in the Apple App Store and Google Play store using relevant keywords and inclusion criteria. Information was extracted for the name of the app, primary and additional functionalities, release and last update, number of downloads, number of marks and average rating, Android/iOS compatibility, initial and in-app payments, data safety statement, physician involvement statement, and FDA/MDR guidance. A total of 986 apps and 222 articles were reviewed, of which based on the inclusion, 83 apps were finally analyzed. The apps were allocated to six categories about their primary purpose: education (n = 8), fluid trackers (n = 54), food content description and calculators (n = 11), diagnosis (n = 3), pre- and intra-operative application (n = 4), and stent trackers (n = 2). Of these apps, the number of apps supported for Android, iOS, and both of them were 36, 23, and 23, respectively. Despite a wide range of apps available for KSD, the participation of doctors in their development, data security, and functionality remains insufficient. Further development of mHealth should be carried out properly under the supervision of urological associations involving patient support groups, and these apps must be regularly updated for their content and data security.

Does unenhanced computerized tomography as imaging standard post-retrograde intrarenal surgery paradoxically reduce stone-free rate and increase additional treatment for residual fragments? Outcomes from 5395 patients in the FLEXOR study by the TOWER group

Background

Assessment of residual fragments (RFs) is a key step after treatment of kidney stones.

Objective

To evaluate differences in RFs estimation based on unenhanced computerized tomography (CT) versus X-rays/ultrasound after retrograde intrarenal surgery (RIRS) for kidney stones.

Design

A retrospective analysis of data from 20 centers of adult patients who had RIRS was done (January 2018-August 2021).

Methods

Exclusion criteria: ureteric stones, anomalous kidneys, bilateral renal stones. Patients were divided into two groups (group 1: CT; group 2: plain X-rays or combination of X-rays/ultrasound within 3 months after RIRS). Clinically significant RFs (CSRFs) were considered RFs ⩾ 4 mm. One-to-one propensity score matching for age, gender, and stone characteristics was performed. Multivariable logistic regression analysis was performed to evaluate independent predictors of CSRFs.

Results

A total of 5395 patients were included (1748 in group 1; 3647 in group 2). After matching, 608 patients from each group with comparable baseline and stone characteristics were included. CSRFs were diagnosed in 1132 patients in the overall cohort (21.0%). Post-operative CT reported a significantly higher number of patients with RFs ⩾ 4 mm, before (35.7% versus 13.9%, p < 0.001) and after matching (43.1% versus 23.9%, p < 0.001). Only 21.8% of patients in the matched cohort had an ancillary procedure post-RIRS which was significantly higher in group 1 (74.8% versus 47.6%, p < 0.001). Age [OR 1.015 95% confidence interval (CI) 1.009-1.020, p < 0.001], stone size (OR 1.028 95% CI 1.017-1.040, p < 0.001), multiple stones (OR 1.171 95% CI 1.025-1.339, p = 0.021), lower pole stone (OR 1.853 95% CI 1.557-2.204, p < 0.001) and the use of post-operative CT scan (OR 5.9883 95% CI 5.094-7.037, p < 0.001) had significantly higher odds of having CSRFs.

Conclusions

CT is the only reliable imaging to assess the burden of RFs following RIRS and urologist should consider at least one CT scan to determine the same and definitely plan reintervention only based on CT rather than ultrasound and X-ray combination.

Image Distortion During Flexible Ureteroscopy: A Laboratory Model Comparing Super Pulsed Thulium Fiber Laser vs High-Power Ho:YAG Laser

Purpose: Digital ureteroscopes employ "chip-on-the-tip" technology that allows for significant improvement in image resolution. However, image distortion often occurs during laser lithotripsy owing to acoustic wave production. We sought to compare image distortion using different laser power settings and distances from the laser fiber tip to the scope for the Super Pulsed Thulium Fiber (SPTF) laser and high-power Holmium:YAG (Ho:YAG) laser. Materials and Methods: Ureteroscopy was simulated using a silicon kidney-ureter-bladder model fitted with a 12F/14F access sheath and the Lithovue™ (Boston Scientific), disposable digital flexible ureteroscope. At defined laser parameters (10, 20, 30 and 40 W, short pulse), a 200-μm laser fiber was slowly retracted toward the tip of the ureteroscope during laser activation. Image distortion was identified, and distance from the laser tip to the scope tip was determined. Data from the two lasers were compared utilizing t-tests. Results: After controlling for frequency, power, and laser mode, utilizing 1.0 J of energy was significantly associated with less feedback than 0.5 J (-0.091 mm, p ≤ 0.05). Increased power was associated with larger feedback distance (0.016 mm, p ≤ 0.05); however, increase in frequency did not have a significant effect (-0.001 mm, p = 0.39). The SPFT laser had significantly less feedback when compared with all Holmium laser modes. Conclusions: Increased total power results in image distortion occurring at greater distances from the tip of the ureteroscope during laser activation. Image distortion occurs further from the ureteroscope with Ho:YAG laser than with SPTF fibers at the same laser settings. In clinical practice, the tip of the laser fiber should be kept further away from the tip of the scope during ureteroscopy as the power increases as well as when utilizing the Ho:YAG system compared with the SPTF laser platform. The SPTF laser may have a better safety profile in terms of potential scope damage.

Laser Efficiency and Laser Safety: Holmium YAG vs. Thulium Fiber Laser

(1) Objective: To support the efficacy and safety of a range of thulium fiber laser (TFL) pre-set parameters for laser lithotripsy: the efficiency is compared against the Holmium:YAG (Ho:YAG) laser in the hands of juniors and experienced urologists using an in vitro ureteral model; the ureteral damage of both lasers is evaluated in an in vivo porcine model. (2) Materials and Methods: Ho:YAG laser technology and TFL technology, with a 200 µm core-diameter laser fibers in an in vitro saline ureteral model were used. Each participant performed 12 laser sessions. Each session included a 3-min lasering of stone phantoms (Begostone) with each laser technology in six different pre-settings retained from the Coloplast TFL Drive user interface pre-settings, for stone dusting: 0.5 J/10 Hz, 0.5 J/20 Hz, 0.7 J/10 Hz, 0.7 J/20 Hz, 1 J/12 Hz and 1 J/20 Hz. Both lasers were also used in three in vivo porcine models, lasering up to 20 W and 12 W in the renal pelvis and the ureter, respectively. Temperature was continuously recorded. After 3 weeks, a second look was done to verify the integrity of the ureters and kidney and an anatomopathological analysis was performed. (3) Results: Regarding laser lithotripsy efficiency, after 3 min of continuous lasering, the overall ablation rate (AR) percentage was 27% greater with the TFL technology (p < 0.0001). The energy per ablated mass [J/mg] was 24% lower when using the TFL (p < 0.0001). While junior urologists performed worse than seniors in all tests, they performed better when using the TFL than Ho:YAG technology (36% more AR and 36% fewer J/mg). In the in vivo porcine model, no urothelial damage was observed for both laser technologies, neither endoscopically during lasering, three weeks later, nor in the pathological test. (4) Conclusions: By using Coloplast TFL Drive GUI pre-set, TFL lithotripsy efficiency is higher than Ho:YAG laser, even in unexperienced hands. Concerning urothelial damage, both laser technologies with low power present no lesions.

A Comparative Study of Stone Re-Treatment after Lithotripsy

The high recurrence rate has always been a problem associated with urolithiasis. This study aimed to explore the effectiveness of single interventions, combined therapies, and surgical and nonsurgical interventions. Herein, three lithotripsy procedures—extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), and ureteroscopic lithotripsy (URSL)—were assessed and a retrospective cohort was selected in order to further analyze the association with several risk factors. Firstly, a population-based cohort from the Taiwan National Health Insurance Research Database (NHIRD) from 1997 to 2010 was selected. In this study, 350 lithotripsy patients who underwent re-treatment were followed up for at least six years to compare re-treatment rates, with 1400 patients without any lithotripsy treatment being used as the comparison cohort. A Cox proportional hazards regression model was applied. Our results indicate that the risk of repeat urolithiasis treatment was 1.71-fold higher in patients that received lithotripsy when compared to patients that were not treated with lithotripsy (hazard ratio (HR) 1.71; 95% confidence interval (CI) = 1.427−2.048; p < 0.001). Furthermore, a high percentage of repeated treatment was observed in the ESWL group (HR 1.60; 95% CI = 1.292−1.978; p < 0.001). Similarly, the PCNL group was also independently associated with a high chance of repeated treatment (HR 2.32; 95% CI = 1.616−3.329; p < 0.001). Furthermore, age, season, level of care, and Charlson comorbidities index (CCI) should always be taken into consideration as effect factors that are highly correlated with repeated treatment rates.

Reverse Trendelenburg Lithotomy with Certain Inclination Angles Reduces Stone Retropulsion during Ureteroscopic Lithotripsy for Proximal Ureteral Stone

The objective of this study is to investigate how different inclination angles of reverse Trendelenburg lithotomy affect stone retropulsion and stone-free rates during ureteroscopic lithotripsy for proximal ureteral stones. Patients with proximal ureteral stones undergoing ureteroscopic lithotripsy in our institution between January 2019 and December 2020 were included according to predefined criteria. The rigid ureteroscope and Holmium: YAG laser were utilized to perform lithotripsy, and a stone basket was used to keep the stone in place and to avoid retropulsion. Before initiating lithotripsy, the upper part of the patient’s body was tilted up to establish a reverse Trendelenburg posture with appropriate inclination angles. To quantify the stone-free rate, computed tomography was used to evaluate the residual stones in the kidney one month following surgery. Patients’ clinical data were obtained retrospectively, including age, gender, the largest diameter of stone, stone density on computed tomography, and the distance between stone and ureteral pelvic junction, etc. Patients were divided into four groups based on the inclination angles of reverse Trendelenburg lithotomy: 0°, 10°, 20°, and 30°. The chi-square test was used to compare stone retropulsion and stone-free rates between groups. To discover possible determinants of the stone-free rate, logistic regression analyses were used. There were 189 patients that qualified. There were no differences in clinical characteristics between groups (p > 0.05). Multiple comparisons between groups revealed that the 20° and 30° groups had less retropulsion and a greater stone-free rate than the 0° and 10° groups (p < 0.05), whereas there were no significant differences in stone retropulsion or stone-free rates between the 20° and 30° groups or between the 0° and 10° groups (p > 0.05). The inclination angles as well as distance between the stone and ureteral pelvic junction were identified by using logistic regression analyses as the related factors for the stone-free rate. According to our results, the appropriate inclination angles of reverse Trendelenburg lithotomy during ureteroscopic lithotripsy for proximal ureteral stones would help preclude stone retropulsion and increase the stone-free rate.

Shockwaves and the Rolling Stones: An Overview of Pediatric Stone Disease

Urinary stone disease is a common problem in adults, with an estimated 10% to 20% lifetime risk of developing a stone and an annual incidence of almost 1%. In contrast, in children, even though the incidence appears to be increasing, urinary tract stones are a rare problem, with an estimated incidence of approximately 5 to 36 per 100,000 children. Consequently, typical complications of rare diseases, such as delayed diagnosis, lack of awareness, and specialist knowledge, as well as difficulties accessing specific treatments also affect children with stone disease. Indeed, because stone disease is such a common problem in adults, frequently, it is adult practitioners who will first be asked to manage affected children. Yet, there are unique aspects to pediatric urolithiasis such that treatment practices common in adults cannot necessarily be transferred to children. Here, we review the epidemiology, etiology, presentation, investigation, and management of pediatric stone disease; we highlight those aspects that separate its management from that in adults and make a case for a specialized, multidisciplinary approach to pediatric stone disease.

Laser-Assisted Sialolithotripsy: A Correlation of Objective and Subjective Outcomes

OBJECTIVE

To analyze the long-term symptomatic results of laser-assisted sialolithotripsy (LAS) in cases of obstructive sialolithiasis and correlate with objective criteria using diagnostic sialendoscopy (DS) as a method of examination.

METHODS

This is a retrospective study comprising 50 consecutive patients who underwent holmium-YAG LAS and completed follow-up of at least 6 months. Symptom scoring and endoscopic scoring were done at 6 weeks and 6 months intervals for further study purposes.

RESULTS

At the end of 6 weeks post-LAS, 70% patients were asymptomatic (A-sym) and only 30% had residual symptoms (Sym). However, obstructed duct (OB-duct) was observed on endoscopic scoring in 88% due to stenosis, residual stones, or both stenosis and residual stones. The obstructed ducts were treated in outpatient clinic and followed up over time, leading to 98% of patients being in A-sym group at the end of study period of 6 months. At the end of study, 82% of patients had clear duct (CL-duct).

CONCLUSION

Holmium LAS is a viable option for the management of intermediate-sized stones. LAS if used judiciously, and in properly selected cases, has high rate of stone fragmentation and symptom resolution. A vigilant postoperative protocol taking into account residual mealtime symptoms and altered salivary characteristics combined with early DS can help identify and treat patients with residual stone fragments and ductal stenosis.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:2344-2349, 2022.

Feasibility of Laser Lithotripsy for Midsize Stones Using Robotic Retrograde Intrarenal Surgery System easyUretero in a Porcine Model

Purpose: To test the safety and feasibility of laser lithotripsy for midsize renal stones using a newly developed robotic retrograde intrarenal surgery (RIRS) system (easyUretero) in a porcine model. Materials and Methods: Three urologic surgeons representing three different RIRS experience levels (beginner, intermediate, and expert) participated. Four female pigs (aged 6 months) underwent manual or robotic RIRS. Under general anesthesia, a nephrostomy tract was created ventrally, and calcium stones (diameter, 1.0-1.5 cm) were inserted at renal calices. For manual RIRS, surgeons operated a flexible ureteroscope. For robotic RIRS, the ureteroscope was attached to the robotic slave device. The Auriga XL™ Holmium laser was used for lithotripsy. Lasering and stone retrieval time were measured. Kidneys and ureters were inspected for injury at the end of each session. Results: For the expert, both lasering and stone retrieval by manual RIRS were quicker than by robotic RIRS (22.8 ± 11.0 s/stone vs 234.5 ± 102.5 s/stone, p = 0.02; 41.5 ± 0.5 s/stone vs 79.3 ± 8.1 s/stone, p = 0.02). For the intermediate and beginner, lasering and stone retrieval times were not significantly different between manual and robotic procedures (127.8 ± 93.2 s/stone vs 284.8 ± 112.3 s/stone, p = 0.08; 86.0 ± 30.5 s/stone vs 84.1 ± 21.4 s/stone, p = 0.92). All stones were removed. Grade 1 ureteral and renal injuries occurred in both manual RIRS and robotic RIRS. Conclusions: The laser lithotripsy using the easyUretero robotic system is safe and feasible in a porcine model, even for less-experienced surgeons.

Laser Heating of Fluid With and Without Stone Ablation: In Vitro Assessment

Introduction: Laser lithotripsy can cause excessive heating of fluid within the collecting system and lead to tissue damage. To better understand this effect, it is important to determine the percentage of applied laser energy that is converted to heat and the percentage used for stone ablation. Our objective was to calculate the percentage of laser energy used for stone ablation based on the difference in fluid temperature measured in an in vitro model when the laser was activated without and with stone ablation. Methods: Flat BegoStone disks (15:5) were submerged in 10 mL of deionized water at the bottom of a vacuum evacuated double-walled glass Dewar. A Moses 200 D/F/L laser fiber was positioned above the surface of the stone at a distance of 3.5 mm for control (no stone ablation) or 0.5 mm for experimental (ablation) trials. The laser was activated and scanned at 3 mm/second across the stone in a preprogrammed pattern for 30 seconds at 2.5 W (0.5 J × 5 Hz) for both short-pulse (SP) and Moses distance (MD) modes. Temperature of the fluid was recorded using two thermocouples once per second. Results: Control trials produced no stone ablation, while experimental trials produced a staccato groove in the stone surface, simulating efficient lithotripsy. The mean temperature increase for SP was 1.08°C ± 0.04°C for control trials and 0.98°C ± 0.03°C for experimental trials, yielding a mean temperature difference of 0.10°C ± 0.06°C (p = 0.0005). With MD, the mean temperature increase for control trials was 1.03°C ± 0.01°C and for experimental trials 0.99°C ± 0.06°C, yielding a smaller mean temperature difference of 0.04°C ± 0.06°C (p = 0.09). Conclusions: Even under conditions of energy-efficient stone ablation, the majority of applied laser energy (91%-96%) was converted to heat.