The Application of Next-Generation Sequencing in Preoperative Evaluation for Urologic Stone Surgery.

Introduction: Next-generation sequencing (NGS) is a new molecular technique for identifying microorganisms. Treating bacteriuria in patients undergoing stone removal procedures is important for preventing postoperative urinary tract infection (UTI). The objective of this study is to assess the usefulness of preoperative urine NGS testing by comparing NGS with standard urine culture in predicting postoperative UTI after ureteroscopic lithotripsy (URSL) and percutaneous nephrolithotomy (PCNL). Materials and Methods: This prospective study was conducted from February 16, 2022, to January 11, 2024. Sixty subjects who underwent URSL or PCNL were included. Preoperative voided urine samples were collected for urine culture and tested by MicroGenDX for urine polymerase chain reaction (PCR) and urine NGS. Stone specimens obtained intraoperatively were also sent for stone culture and MicrogenDx. Patients were monitored for 4 weeks post-operation for recording clinical outcomes related to infections and complications. Results: Twenty-six (43.3%) male and 34 (56.7%) female participants were included. Twenty-six (43.3%) patients underwent PCNL (15 standard PCNL and 11 mini PCNL), and 34 (56.7%) underwent URSL. Standard urine culture identified positive results in 26 cases (43.3%), PCR for 17 cases (28.3%), and NGS for 31 cases (51.7%). The overall postoperative UTI rate was 6 (10%). Standard urine culture demonstrated a sensitivity of 50%, specificity of 57.4%, and accuracy of 56.7%. Positive predictive value (PPV) was notably poor at 11.5%. Urine NGS showed a higher sensitivity of 83.3%, specificity of 53.7%, accuracy of 55%, and PPV of 16.7%. Conclusion: Urine NGS significantly improves the sensitivity of detecting microorganisms in preoperative urine compared with standard urine culture. Despite its high sensitivity and capability to identify nonculturable bacteria, using NGS alongside standard urine culture is recommended. This parallel approach harnesses the strengths of both methods. Integrating NGS into standard practice could elevate the quality of care, especially for patients at high risk of UTIs, such as those undergoing invasive stone removal procedures.

Feasibility assessment of catheter-free water vapor thermal therapy for treatment of benign prostatic hyperplasia.

PURPOSE: To investigate safety and feasibility of performing water vapor thermal therapy (WVTT; Rezum, Boston Scientific, Marlborough, MA, USA) without postoperative catheterization among men with benign prostatic hyperplasia. METHODS: This is a prospective, single arm, unblinded pilot study of 20 consecutive male patients ages 40-80 who underwent WVTT at a single academic institution. All patients underwent 1 injection per lobe at the point of maximal obstruction based on visualization. Primary outcome was evaluation of voiding parameters, symptom scores, and need for catheterization at 3 day, 1, 3, and 6 month follow up compared to baseline visit 30 days prior to surgery. RESULTS: Mean age was 65 years (range 55-75). Mean prostate volume and PVR were 43 cc (range 30-68) and 89 cc, with 30% (n = 6) having median lobes. Patients received 2-3 treatments based on presence of bilobar versus trilobar hyperplasia. One patient (55 cc prostate, no median lobe) required catheterization for acute urinary retention on postoperative day 2. No patients required antibiotics for urinary tract infection or inpatient readmission within 30 days. Qmax significantly increased from 6 mL/s to 8, 13, 12, and 14 at 3 days, 1, 3, and 6 months (p < 0.05). IPSS decreased from 17 preoperatively to 10, 6, 7, and 8 (p < 0.05). No significant differences were noted in PVR, IIEF, MSHQ-EjD, or SF-12. CONCLUSIONS: In well-selected men, catheter-free WVTT is feasible and improved voiding parameters and symptom scores. No changes in sexual function, infectious complications, or readmission were noted. Only 1 patient (5%) required postoperative catheterization within 30 days.

Levels of anti-insulin antibodies in diabetic retinopathy patients: an observational cross-sectional study.

Aim: This study evaluated the levels of anti-insulin antibodies (AIAs) and the influence of some antidiabetic medications on AIA in diabetes mellitus (DM) patients with retinopathy. Patient & methods: An observational cross-sectional study. Results: A lower titer of AIA IgG was observed in the diabetic retinopathy (DR) and DM-only study categories compared with the control group [DR = 86 (5-560), DM-only = 50 (5-500), versus control = 200 (7-565); p = 0.017]. Taking nifedipine and metformin were negatively correlated (r = -0.32, p = 0.04) with the levels of AIA IgE in the DR group. Conclusion: A decreased titer of circulating AIAs was observed in the DR study category, suggesting that AIA may not contribute to the pathogenesis of DR.

Diabetic retinopathy (DR) is the main reason people lose their sight in countries with few resources. Anti-insulin antibodies, or AIAs, help the body fight off infections and may play a role in the development of DR. The study looked at how much AIA was in DR patients and how some diabetes drugs affected AIA levels. There was a negative link between nifedipine and one AIA (IgE) in people with DR, but a positive link between metformin and another AIA (IgG). AIA levels were lower in the DR study group, which suggests that AIA may not cause DR.

Diagnostic utility of selected faecal biochemical parameters in the determination of acute diarrhoea and associated defecation stooling characteristics in dogs: An observational study.

Diarrhoea, which is a clinical manifestation of various illnesses, is frequently observed in dogs. Regrettably, many dog owners find it difficult to provide comprehensive case histories, primarily because of limited interaction with their canine companions. This study aimed to evaluate the potential of faecal biochemical analytes in detecting and characterizing acute diarrhoea in dogs. Sixty-two domestic dogs were selected using the proportionate stratified sample technique. A structured questionnaire was used to collect demographic and clinical data. Faecal stool specimens from the dogs were obtained using the colon flush technique. The specimens were taken through biochemical analysis to determine urea, creatinine, total bilirubin, total cholesterol, triglycerides, gamma-glutamyl transferase and uric acid levels. Results showed a significant association between the diarrhoea status of the participants and their age, weight, breed, body size, source of last diet, period of inappetence, and other gastrointestinal signs (p < 0.050, respectively). Dogs that had not eaten in at least three days were five times more likely (p < 0.05) to have diarrhoea. Furthermore, miniature breeds were about six times more likely to develop diarrhoea (p < 0.05). Of the seven selected biochemical parameters, total faecal cholesterol was the most predictive index in diagnosing acute diarrhoea in dogs, with a likelihood ratio of 6.5, and it was the most accurate in predicting defecation stooling frequency and texture. In summary, in situations of inadequate case histories, measuring total faecal cholesterol could assist veterinarians in detecting diarrhoea and predicting its faecal stooling texture and frequency in dogs.

Retreatment for Lower Urinary Tract Symptoms After Water Vapor Thermal Therapy.

OBJECTIVE: To identify predictors of retreatment for symptomatic recurrence among men who undergo water vapor thermal therapy (WVTT; Rezum, Boston Scientific, Marlborough, MA), a minimally invasive surgical treatment for lower urinary tract symptoms secondary to benign prostatic hyperplasia. METHODS: We retrospectively reviewed patients treated with WVTT at a single institution from August 2017 to February 2022. Patients who underwent a second benign prostatic hyperplasia procedure for persistent or recurrent lower urinary tract symptoms within 2years of original treatment were compared to the remaining cohort who did not undergo retreatment. Multivariate analysis was used to assess for predictors of retreatment. RESULTS: Data were obtained from 192 patients. 10 (5%) patients were retreated. The retreatment cohort had smaller prostate volumes (50.4±18.2 cc vs 48.5±35.7 cc; P = .003) and received a greater number of water vapor injections (4.4±1.8 vs 5.2±3.9; P < .001). At 6month follow-up, total International Prostate Symptom Score (IPSS; 10.13 ± 7.40 vs 18.5 ± 11.55, P = .044) and voiding subscores (4.59 ± 4.39 vs 9.5 ± 7.84, P = .006) were significantly worse in the retreatment group. On multivariate analysis, >1 treatment per lobe was independently associated with increased risk of retreatment (hazard ratio 8.509, 95% CI [1.109-65.293]; P = .039). CONCLUSION: WVTT has a low retreatment rate. Men who required retreatment received more injections and showed worsened voiding symptom scores 6months postoperatively. Decreasing the number of injections may help reduce treatment failure rates.

Spine surgeon triage of new patient referrals: quantification of surgical conversion rate by clinic referral source.

BACKGROUND CONTEXT: In an effort to efficiently deliver high-value spine surgical care, spine surgery clinics may triage new patient referrals. A triage system with attending surgeon review of referred patient images may improve the surgical conversion rate (SCR) of a spine surgical clinic, and shift the distribution of new patients in clinic toward those most likely to derive benefit from surgery. PURPOSE: To quantify SCR and number of triage steps by referral source in a tertiary referral spine clinic where all referrals are triaged by attending surgeons. DESIGN: All spine surgery clinic patients seen for a new patient visit (NPV) at an academic medical center over a one-year period had their triage process and outcome (surgery or no surgery) reviewed. PATIENT SAMPLE: The 1398 new adult patients seen for elective spine pathology were queried. OUTCOME MEASURES: SCR was defined as the percentage of new patients who underwent elective spine surgery within 18 months of NPV. Triage steps were defined as an action item by triage staff (ie, obtaining patient records) or by the patient (ie, undergoing additional imaging). METHODS: All new patient visits were evaluated for referral source, number of triage steps, and triage outcome. Time from referral to NPV, and time from NPV to surgery were also recorded. SCR, triage steps, and time-intervals were calculated for each surgeon and referral source and compared. Statistical analysis of variance (ANOVA) was used to ascertain differences. RESULTS: The overall SCR for the 4-surgeon group was 41.6%. This ranged among the surgeons from 24.7% to 60.1%. The referral sources with the highest SCR were in-system spine advanced practice providers (APPs) and in-system physical medicine and rehabilitation providers. Spine APPs also demonstrated the smoothest referral process, requiring the fewest steps. CONCLUSIONS: Our findings provide a framework for assessment of triage processes at other institutions, as well as the impact of upgrades to our triage process as we work to improve triage efficiency. In the present study, referrals from providers familiar with spine pathology resulted in the highest SCR and fewest triage steps.

The impact of kidney stone disease on quality of life in high-risk stone formers.

OBJECTIVE: To assess the impact of kidney stone disease (KSD) and its treatment on the health-related quality of life (HRQOL) of high-risk stone formers with hyperparathyroidism, renal tubular acidosis, malabsorptive disease, and medullary sponge kidney. PATIENTS AND METHODS: The Wisconsin Stone Quality of Life questionnaire was used to evaluate HRQOL in 3301 patients with a history of KSD from 16 institutions in North America between 2014 and 2020. Baseline characteristics and medical history were collected from patients, while active KSD was confirmed through radiological imaging. The high-risk group was compared to the remaining patients (control group) using the Wilcoxon rank-sum test. RESULTS: Of 1499 patients with active KSD included in the study, the high-risk group included 120 patients. The high-risk group had significantly lower HRQOL scores compared to the control group (P < 0.01). In the multivariable analyses, medullary sponge kidney disease and renal tubular acidosis were independent predictors of poorer HRQOL, while alkali therapy was an independent predictor of better HRQOL (all P < 0.01). CONCLUSIONS: Among patients with active KSD, high-risk stone formers had impaired HRQOL with medullary sponge kidney disease and renal tubular acidosis being independent predictors of poorer HRQOL. Clinicians should seek to identify these patients earlier as they would benefit from prompt treatment and prevention.

Prospective Multicenter Evaluation of Pain Before and After Removal of Nonobstructing Renal Calculi: A CoRE Initiative.

PURPOSE: Flank pain associated with stone disease is typically caused by a stone that obstructs urine flow. However, it is plausible that nonobstructing kidney stones may still cause pain. We performed a multicenter, observational trial to evaluate whether treatment of small nonobstructing calyceal stones improves pain and kidney stone-specific health-related quality of life. MATERIALS AND METHODS: Patients aged 18 years or older with nonobstructing renal stone(s) up to 10 mm in longest diameter and moderate to severe pain were recruited. All participants completed 3 questionnaires: the Brief Pain Inventory (BPI), the Patient-Reported Outcomes Measurement Information System pain interference form 6a, and the Wisconsin Stone Quality of Life questionnaire. Thereafter, all participants underwent ureteroscopy for renal stone treatment. All 3 questionnaires were repeated at 2, 6 to 8, and at 12 weeks postprocedure. The primary outcomes were change in preoperative to 12-week postoperative mean BPI score and worst BPI pain score. RESULTS: A total of 43 patients with nonobstructing kidney stones and associated flank pain were recruited. All stones were removed. Preoperatively, BPI scores for mean pain and worst pain were 5.5 and 7.2, respectively which decreased to 1.8 and 2.8 respectively at 12 weeks postoperatively. Wisconsin Stone Quality of Life questionnaire mean score increased from 70.4 to 115.3 at 12 weeks postoperatively. A total of 86% and 69% of patients had at least a 20% and 50% reduction in their mean pain scores, respectively. CONCLUSIONS: This study determined that patients benefit significantly from the removal of calyceal nonobstructing kidney stones for at least 12 weeks with a reduction in pain and an increase in quality of life. Therefore, surgical removal of these stones in this patient population should be offered as a treatment option.

The Effect of Pre-Stenting on Bleeding-Related Complications Following Ureteroscopy in Patients on Anticoagulation or Antiplatelet Therapy.

Introduction: The American Urological Association guidelines state that continuing anticoagulant (AC) and antiplatelet (AP) agents during ureteroscopy (URS) is safe. Through a multi-institutional retrospective study, we sought to determine whether pre-stenting in patients on AP or AC was associated with fewer URS bleeding-related complications. Methods: A series of 8614 URS procedures performed across three institutions (April 2010 to September 2017) was electronically reviewed for AC/AP use at time of URS. Records indicating AC or AP use at time of URS were then manually reviewed to characterize intraoperative and 30-day postoperative (intraoperative bleeding, postoperative hematuria, emergency department visits, hospital readmission, unplanned reoperation, phone calls, and other minor 30-day complications). Results: A total of 293 identified URS procedures were completed on patients on AC/AP therapy-112 cases were on AC only (38 were pre-stented), 158 on AP only (51 pre-stented), and 23 on both AP and AC (8 pre-stented). Patient characteristics and comorbidities were similar between the pre-stented and non-pre-stented groups. For AC and AP subjects, pre-stenting did not decrease the composite risk of bleeding complications (10.3% pre-stent vs 12.2% non-prestent, p = 0.6). Pre-stented patients did have a significantly lower likelihood of requiring an unplanned reoperation (1.0% vs 5.6%, p = 0.04). In the subgroup of patients on AP alone, pre-stented patients had significantly fewer episodes of intraoperative bleeding (0% vs 9%, p = 0.04), unplanned reoperations (0% vs 6.5%, p = 0.02), and 30-day complications (14% vs 27%, p = 0.05). In the subgroup of patients on AC alone, there were no significant differences in outcomes based on stent status. Conclusions: In this multi-institutional study, we found that pre-stenting before URS was not associated with fewer bleeding complications. However, pre-stenting appeared to be associated with improved outcomes for those patients on AP therapy. These results suggest a need for prospective studies to clarify the role of pre-stenting for URS.

Blood C-peptide concentration as a proxy marker of cardiovascular disease: An observational cross-sectional study.

Background and Aims: Cardiovascular diseases (CVDs) are among the leading causes of disability and early death in sub-Saharan Africa. Most of the current blood tests for CVD diagnosis involve performing about three test profiles; often at additional cost to patients. C-peptide, a cleavage product of proinsulin, is a promising marker that has the potential to serve as a proxy marker for diagnosing CVDs in resource-poor settings. Methodology: The study was an observational cross-sectional one and involved 127 consenting persons diagnosed with CVD and 127 individuals without CVD. The socio-demographic and clinical characteristics of participants were obtained. Blood levels of C-peptide, fasting plasma glucose (FPG), total creatinine kinase (CK), creatine kinase myocardial bound (CKMB), lactate dehydrogenase (LDH), propeptide of brain natriuretic peptide (PBNP), Troponin T, lipids, and biomarkers of kidney and liver function were analyzed using ELISA and an automated analyzer. Insulin resistance was computed using the modified homeostatic model assessment (HOMA-IR). Results: The CVD Group had significantly higher levels of C-peptide, CK, CKMB, troponin T, PBNP, FPG, HOMA-IR, and several selected kidney, liver, and lipid parameters compared to the non-CVD Group (p < 0.05 for all). Troponin T recorded a positive correlation (r = 0.34, p < 0.001) with C-peptide among the CVD Group. The sensitivity and specificity of C-peptide in identifying CVD were 96.1% and 91.3% respectively (area under the curve = 0.938, p < 0.001). Conclusion: C-peptide levels were higher in the CVD Group and appeared to be a valuable (high sensitivity and specificity) biomarker in detecting CVD.

The Impact of Bilateral Stone Disease on Patients' Disease Progression and Health-Related Quality of Life.

Purpose: Patients with recurring kidney stone events can expect significant morbidity and functional impairment. Few studies have evaluated the effect of bilateral kidney stones on disease progression and quality of life. We wanted to determine the association of bilateral stone disease on age of onset, and the impact on number of stone events and individual kidney stone disease-specific health-related quality of life (HRQOL) by analyzing the validated and prospectively collected Wisconsin Stone Quality of Life (WISQOL) database. Materials and Methods: We studied 2906 stone patients from 16 centers in North America after having completed the WISQOL questionnaire from 2014 to 2019. Kidney stone formers were assessed if kidney stones were bilateral or unilateral on imaging. Analysis with a chi-square test compared categorical variables. Bilateral kidney stone disease and its impact on HRQOL were evaluated through a multivariable linear regression model. Results: Of 2906 kidney stone formers, 1340 had unilateral kidney stones and 1566 had bilateral kidney stones. We observed more frequently that patients with bilateral stones had an increased number of depression/anxiety symptoms, renal tubular acidosis, and rheumatoid arthritis (all p < 0.05). Patients with bilateral stones had a younger mean (standard deviation [SD]) age of kidney stone disease onset (37.2 ± 15.8 vs 46.4 ± 15.9 years of age, p < 0.001). Bilateral kidney stone formers had a higher mean (SD) number of stone events (11.3 ± 21.8) than unilateral kidney stone formers (3.0 ± 5.1) (p < 0.001). Within our multivariable analysis, we found that HRQOL was negatively affected by the presence of bilateral stones for kidney stone patients (ß = -11.2 [confidence interval: -19.5 to -3.0] points, p < 0.05). Conclusions: Bilateral kidney stone formers had a younger age of kidney stone disease onset and a higher number of stone events compared with unilateral kidney stone disease formers. The presence of bilateral kidney stone disease negatively impacted HRQOL.

Erector spinae plane blocks for analgesia after percutaneous nephrolithotomy A pathway to reduce opioids.

INTRODUCTION: Despite its minimally invasive nature, percutaneous nephrolithotomy (PCNL ) may be associated with significant pain. Challenges in pain control may prevent timely discharge (and expose patients to adverse effects of opioid use). We sought to evaluate whether our patients who underwent erector spinae plane (ESP) regional blocks experienced improved postoperative pain control and decreased opioid use after PCNL (compared with those who did not receive blocks). METHODS: We retrospectively reviewed consecutive PCNL cases on patients admitted for greater than 24 hours without pre-existing opioid regimens for chronic pain. Cases were completed by a single high-volume surgeon. Patients who accepted an ESP block were compared to those who did not receive a block. Patients received either a single injection or a disposable pump delivering intermittent boluses of ropivacaine 0.2%. Demographic and perioperative data were analyzed. The primary outcomes were opioid use measured in morphine milligram equivalent (MME ) and patient-reported pain scores during the first 24 hours of hospitalization. RESULTS: From March 2019 to August 2021, 44 patients were identified who met criteria - 28 of whom received an ESP block (including 14 continuous blocks). The patients who received blocks had significantly decreased opioid use (18.3 vs. 81.3 MME, p=0.004) and a longer mean time to first non-zero pain score (p=0.004). Continuous blocks had similar opioid use to single shot blocks (21.0 vs. 15.6 MME, p=0.952). CONCLUSIONS: ESP regional blocks appear to offer an effective adjunct method for pain control after PCNL and may reduce post-PCNL opioid use while maintaining adequate patient analgesia.

Quick Sequential Organ Failure Assessment Score Is a Better Predictor of Septic Shock After Percutaneous Nephrolithotomy: A Secondary Analysis of Two Multicenter Prospective Trials.

Introduction: Recent retrospective literature suggests that the quick sequential organ failure assessment (qSOFA) scoring tool is a potentially superior tool over use of the systemic inflammatory response syndrome (SIRS) criteria to predict septic shock after percutaneous nephrolithotomy (PCNL) surgery. Here we examine use of qSOFA and SIRS to predict septic shock within data series collected prospectively on PCNL patients as part of a greater study of infectious complications. Materials and Methods: We performed a secondary analysis of two prospective multicenter studies including PCNL patients across nine institutions. Clinical signs informing SIRS and qSOFA scores were collected no later than postoperative day 1. The primary outcome was sensitivity and specificity of SIRS and qSOFA (high-risk score of greater-or-equal to two points) in predicting admission to the intensive care unit (ICU) for vasopressor support. Results: A total of 218 cases at 9 institutions were analyzed. One patient required vasopressor support in the ICU. The sensitivity/specificity was 100%/72.4% (McNemar's test p < 0.001) for SIRS and was 100%/90.8% (McNemar's test p < 0.001) for qSOFA. Conclusion: Although positive predictive value for both qSOFA and SIRS in prediction of post-PCNL septic shock is low, prospectively collected data demonstrate use of qSOFA may offer greater specificity than SIRS criteria when predicting post-PCNL septic shock.

District-level analysis of socio-demographic factors and COVID-19 infections in Greater Accra and Ashanti regions, Ghana.

Since December 2019 when COVID-19 was detected, it took the world by surprise in terms of spread and morbidity/mortality. The high rate of spread and casualties recorded from COVID-19 called for research in all directions to find ways to contain and reverse the incidences. It is against this background that this paper sought to measure the association of the socio-demographic factors in the hard-hit districts in Greater Accra and Ashanti to analyze its relationship with the novel COVID-19 virus. Data on COVID-19 cases from 35 Districts in both Greater Accra and Ashanti Regions were collected from the Ghana Health Service and population data from Ghana Statistical Service. Descriptive statistics and regression analysis were generated using R. We found that some socio-demographic variables have an association with COVID-19 infections. For example, age and religion especially Christianity and Islam pose risk to COVID-19. The population aged 15-64 was particularly at high risk of infections due to the high level of movement of this age group. We, therefore, recommend that places of congregation such as Churches and Mosques be targeted for vigorous sensitization on COVID-19 protocols and prevention. Also, districts with a high population between the ages of 15-64 should step sensitization efforts to educate their inhabitants on the need to reduce travel and related activities to curb the spread of the virus.

Long-term follow-up on dusting versus basketing during ureteroscopy: a prospective multicenter trial from the EDGE Research Consortium.

In 2018, the Endourology Disease Group for Excellence (EDGE) published a prospective trial comparing dusting versus basketing during ureteroscopy. One hundred fifty-nine patients were included in the original analysis, which found no difference in stone-free rate at 3 months. We report the intermediate and long-term outcomes of patients included in the original trial. Two analyses were performed. At 1-year, a retrospective chart review was performed, and data collected on stone episodes, Emergency Department (ED) visits, hospital admissions and surgical interventions. To obtain long-term outcomes, the four sites with the largest initial accrual were included in a second phase of data collection with updated analyses. The patients from those sites were contacted, re-consented, and data were collected on stone surgical interventions, stone episodes, stone recurrences on imaging, emergency department (ED) visits, and hospital admissions for stone-related care since their original procedure. One-year follow-up data were collected in 111 of the original 159 (69.8%) patients from the nine sites. There were no statistically significant differences in the number of painful episodes, ED visits, hospital admissions, or surgical interventions. 94 patients from four sites were included in the long-term analysis. There were no statistically significant differences in surgical interventions, painful stone episodes, stone recurrence on imaging, ED visits or hospitalizations for stone-related events between the two groups. Long-term outcomes of dusting versus basketing during ureteroscopy indicate that there are no significant differences in clinical outcomes between the two surgical modalities.

The Fate of Residual Fragments After Percutaneous Nephrolithotomy: Results from the Endourologic Disease Group for Excellence Research Consortium.

Background: Residual fragments (RFs) after percutaneous nephrolithotomy (PCNL) have a significant impact on patients' quality of life and clinical course. There is a paucity of studies that evaluate the natural history of RFs after PCNL. The objective of this study is to compare rates of reintervention, complications, stone growth, and passage in patients with RFs >4, ≤4, and ≤2 mm after PCNL. Methods: Sites from the Endourologic Disease Group for Excellence (EDGE) research consortium examined data of PCNL patients from 2015 to 2019 with at least 1-year follow-up. RF passage, regrowth, reintervention, and complications were recorded and RFs were stratified into >4 and ≤4 mm groups, as well as >2 and ≤2 mm groups. Potential predictors for stone-related events after PCNL were determined using multivariable logistic regression analysis. It was hypothesized that larger RF thresholds would result in lower passage rates, faster regrowth, and greater clinically significant events (complications and reinterventions) than smaller RF thresholds. Results: A total of 439 patients with RFs >1 mm on CT postoperative day 1 were included in this study. For RFs >4 mm, rates of reintervention were found to be significantly higher and Kaplan-Meier curve analysis showed significantly higher rates of stone-related events. Passage and RF regrowth were not found to be significantly different compared with RFs ≤4 mm. However, RFs ≤2 mm had significantly higher rates of passage, and significantly lower rates of fragment regrowth (>1 mm), complications, and reintervention compared with RFs >2 mm. On multivariable analysis, older age, body mass index, and RF size were found to be predictive of stone-related events. Conclusions: With the largest cohort to date, this study by the EDGE research consortium further confirms that clinically insignificant residual fragment is problematic for patients after PCNL, particularly in older more obese patients with larger RFs. Our study underscores the importance of complete stone clearance post-PCNL and challenges the use of Clinically insignificant residual fragment (CIFR).

Clinical Evaluation of Miniature Flexible Scope for Diagnosis of Ureteroscope Working Channel Defects.

Introduction: To evaluate flexible ureteroscope working channels with a 1.06 mm digital borescope (Clarus Medical, Minneapolis, MN) and identify factors contributing to ureteroscope damage over time. Materials and Methods: We performed a single institutional prospective study of patients undergoing stone surgery using a nondisposable flexible ureteroscope. A 1.06 mm borescope was used to evaluate ureteroscopes before and after surgery. Borescope videos were reviewed by two independent researchers to quantify average pre- and postprocedural damage. Results: Twenty-five procedures were performed with pre- and postprocedural borescope assessment between August 2021 and February 2022. All patients received preoperative CT imaging depicting a mean axial stone size of 14.1 ± 8.4 mm and density of 923.4 ± 458.1 HU. Mean operative time was 63.8 ± 34.0 minutes. The average number an instrument passes through the working channel was 2.1 ± 1.6. Laser was used in 11 cases with mean laser time of 18.8 ± 19.7 minutes and mean total energy of 5.8 ± 4.2 KJ. On preoperative assessment, all ureteroscopes had some form of defect (24% shave, 32% pinhole, 96% dents and scratches, and 28% discolorations). During postoperative assessment, 23/25 (92%) ureteroscopes showed additional damage with an average of 3.7 ± 2.8 imperfections acquired after one use. Significant differences were seen in acquired shavings (p = 0.028) and scratches or dents (p = 0.018). Of the 355 imperfections seen on postoperative evaluation, 0.4% were shave, 3% were pinhole, 85.8% were dents and scratches, and 10.8% were discolorations. Conclusion: The Clarus borescope observed defects after the majority of flexible ureteroscopy procedures for nephrolithiasis. Although such disruptions may not immediately render ureteroscopes nonfunctional, they are more common than previously described and could increase maintenance costs. Further studies are needed to investigate the burden of unit damage per procedure to raise operator awareness and reduce preventable ureteroscope imperfections.