Ureteroscopic Stone Extraction Research Articles

Bilateral ureteral stones; factors affecting treatment decision.

To evaluate certain factors that may affect the decision-making process for the rational management approach in cases presenting with bilateral ureteral stones. A total of 153 patients presenting with bilateral ureteral stones from 6 centers were evaluated and divided in three groups. Group 1 (n:21) Patients undergoing DJ stent insertion in one ureter and ureterorenoscopic (URS) lithotripsy for the contralateral ureteral stone. Group 2 (n:91), URS lithotripsy for both ureteral stones and Group 3 (n:41) patients undergoing bilateral DJ stent insertion. The outcomes of the procedures and the relevant patient as well as stone related factors have been comparatively evaluated in three groups. While associated UTI rates and serum creatinine levels were significantly higher in bilateral DJ group, previous URS history was found to be significantly higher in cases undergoing bilateral URS than those undergoing bilateral DJ stenting. URS was performed significantly more often in cases with lower ureteral stones and DJ stenting seems to be more rational approach in upper ureteral stones. In patients with lower ureteral stones, larger and harder stones, endourologists tended to perform URS as the first option. Decision making for a rational approach in cases with bilateral ureteral stones my be challenging. Our findings demonstated that serum creatinine levels, associated UTI, location and the hardness of the stone and previous ureteroscopy anamnesis could be important factors in making a decision between JJ stenting and ureteroscopic stone extraction in emergency conditions.

MP75-15 ASSESSING FACTORS CONTRIBUTING TO DISPARITIES IN KIDNEY STONE MANAGEMENT

You have accessJournal of UrologyCME1 Apr 2023MP75-15 ASSESSING FACTORS CONTRIBUTING TO DISPARITIES IN KIDNEY STONE MANAGEMENT Marvin A. Meza Jarquín, Ram S. Basak, David F. Friedlander, Gopal L. Narang, and Davis P. Viprakasit Marvin A. Meza JarquínMarvin A. Meza Jarquín More articles by this author , Ram S. BasakRam S. Basak More articles by this author , David F. FriedlanderDavid F. Friedlander More articles by this author , Gopal L. NarangGopal L. Narang More articles by this author , and Davis P. ViprakasitDavis P. Viprakasit More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003349.15AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Studies suggest that there is a disproportionately increasing prevalence of kidney stone disease among African American and Hispanic patients in the United States. Furthermore, evidence indicates that disparities exist in the workup, management, and surgical interventions of different diseases based on race, ethnicity and socioeconomic status, among other variables. We sought to explore the potential non-clinical factors that could lead to disparities in the management of patients with symptomatic nephrolithiasis at a tertiary care center serving a mixed urban and non-urban population. METHODS: We retrospectively analyzed consecutive non-established adult patients presenting with symptomatic unilateral nephrolithiasis requiring definitive ureteroscopic stone extraction at a single institution between October 2019 and September 2021. The primary endpoint was time in days from the date of referral to the date of definitive treatment. Other variables included patient demographics, clinical characteristics, need for preoperative decompression, referral source, treatment date in relation to the COVID-19 pandemic, and Area Deprivation Index (ADI) ranking, a validated measure of neighborhood adversity related to education, employment, housing, and income. RESULTS: Of 398 included patients, the mean age was 53 years, 55% female and 75% Caucasian. 47% had private insurance, 40% had government assistance and 13% were uninsured. The majority (73%) of referrals were from the emergency department. 10% of patients had a urinary tract infection on presentation. Renal obstruction was present in 77% of patients with 40% requiring preoperative decompression. The overall mean time from referral to surgery was 29 days (IQR 15-36). Factors associated with significantly longer time to surgery included Hispanic identity (40 days IQR 12-68, p=0.0098) compared to other ethnicities, Medicaid insurance (36 days IQR 17-55, p=0.012) compared to other payer groups and patients within the highest tertile ADI (most disadvantaged) ranking (+8 days, p=0.022) compared to those in the lowest tertile (most advantaged). CONCLUSIONS: In our cohort we demonstrated several non-clinical factors that resulted in a delay to definitive treatment in symptomatic kidney stone patients including Hispanic identity, Medicaid insurance, and most disadvantaged ADI ranking. Recognition of such disparities is the first step to help delineate and eliminate the barriers delaying the care of these vulnerable patients. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1086 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Marvin A. Meza Jarquín More articles by this author Ram S. Basak More articles by this author David F. Friedlander More articles by this author Gopal L. Narang More articles by this author Davis P. Viprakasit More articles by this author Expand All Advertisement PDF downloadLoading ...

Ureteroscopic stone extraction is not always needed after urgent drainage for obstructive uropathy due to ureteric stones

Ureteroscopic stone extraction is not always needed after urgent drainage for obstructive uropathy due to ureteric stones

Prediction of burden and management of renal calculi from whole kidney radiomics: a multicenter study.

PurposeTo assess if autosegmentation-assisted radiomics can predict disease burden, hydronephrosis, and treatment strategies in patients with renal calculi.MethodsThe local ethical committee-approved, retrospective study included 202 adult patients (mean age: 53 ± 17 years; male: 103; female: 99) who underwent clinically indicated, non-contrast abdomen-pelvis CT for suspected or known renal calculi. All CT examinations were reviewed to determine the presence (n = 123 patients) or absence (n = 79) of renal calculi. On CT images with renal calculi, each kidney stone was annotated and measured (maximum dimension, Hounsfield unit (HU), and combined and dominant stone volumes) using a HU threshold-based segmentation. We recorded the presence of hydronephrosis, number of renal calculi, and treatment strategies. Deidentified CT images were processed with the radiomics prototype (Radiomics, Frontier, Siemens Healthineers), which automatically segmented each kidney to obtain 1690 first-, shape-, and higher-order radiomics. Data were analyzed using multiple logistic regression analysis with areas under the curve (AUC) as output.ResultsAmong 202 patients, only 28 patients (18%) needed procedural treatment (lithotripsy or ureteroscopic stone extraction). Gray-level co-occurrence matrix (GLCM) and gray-level run length matrix (GLRLM) differentiated patients with and without procedural treatment (AUC 0.91, 95% CI 0.85–0.92). Higher-order radiomics (gray-level size zone matrix – GLSZM) differentiated kidneys with and without hydronephrosis (AUC: 0.99, p < 0.001) as well those with different stone volumes (AUC up to 0.89, 95% CI 0.89–0.92).ConclusionAutomated segmentation and radiomics of entire kidneys can assess hydronephrosis presence, stone burden, and treatment strategies for renal calculi with AUCs > 0.85.

Ureteroscopic Stone Extraction in Cross-Fused Renal Ectopia

Background: Urinary stone disease in cross-fused renal ectopia is rare and the aberrant anatomy poses challenges to treatment options. The available literature on treatment modalities remains limited. In this study, we present a case of ureteral stone in a cross-fused renal ectopia managed through retrograde approach.Case Presentation: We present a case of a 69-year-old woman with an obstructing ureteral stone in a cross-fused renal ectopia managed with ureteroscopic stone extraction. With the use of a ureteral access sheath, holmium laser, and Nitonol basket, the stone was fragmented and removed through retrograde access. The stone composition was 100% calcium oxalate monohydrate and her 24-hour urine collection was only significant for low volume.Conclusion: With special modifications and attention to the individual patient's anatomy, retrograde approach with the use of an access sheath is safe and effective for treatment of ureteral stones in patients with cross-fused renal ectopia.

Assessment of urology postgraduate trainees' competencies in flexible ureteroscopic stone extraction.

We aimed to assess flexible ureteroscopic stone extraction skill of urology postgraduate trainees (PGTs) at an Objective Structured Clinical Examination (OSCE) and to determine whether previous experience in the operating theatre or practice on the simulator correlated with performance. After obtaining ethics approval, PGTs from postgraduate years (PGYs) 3-5 were recruited from all four Quebec urology training programs during an OSCE. After a short orientation to the UroMentor™ simulator, PGTs were asked to perform Task 10 for 15 minutes, where two small stones from the left proximal ureter and renal pelvis were extracted using a basket. Competency of PGTs in performing the task was assessed using objective assessment from the simulator and subjective evaluations using Ureteroscopy-Global Rating Scale (URS-GRS). Simulator performance reports and URS-GRS scores were analyzed. Thirty PGTs (9 PGY-3, 11 PGY-4, 10 PGY-5) participated in this study. PGTs had performed a mean of 55.9 semi-rigid and 45.7 flexible ureteroscopies prior to the study. Mean URS-GRS score of the participants was 20.0±4.4. Using norm-referenced method with three experts, cutoff score of 19 on the URS-GRS was determined to indicate competency. Sixty percent (18/30) of PGTs were competent. All eight PGTs who had practiced on the simulator were competent. Previous experience in the operating theatre and PGY level did not correlate with performance. This study confirmed the feasibility of incorporating the UroMentor at OSCEs to assess competency of urology PGTs in ureteroscopic stone extraction skill. PGTs who practiced on the simulator scored significantly higher than those who did not practice; however, the software needs to be updated to improve its face validity and to include more complex tasks, such as holmium laser lithotripsy. Future studies with larger sample sizes and more complex cases are needed to confirm these results.

Urology Residents' Experience and Attitude Toward Surgical Simulation: Presenting our 4-Year Experience With a Multi-institutional, Multi-modality Simulation Model

To evaluate the Urological resident's attitude and experience with surgical simulation in residency education using a multi-institutional, multi-modality model. Residents from 6 area urology training programs rotated through simulation stations in 4 consecutive sessions from 2014 to 2017. Workshops included GreenLight photovaporization of the prostate, ureteroscopic stone extraction, laparoscopic peg transfer, 3-dimensional laparoscopy rope pass, transobturator sling placement, intravesical injection, high definition video system trainer, vasectomy, and Urolift. Faculty members provided teaching assistance, objective scoring, and verbal feedback. Participants completed a nonvalidated questionnaire evaluating utility of the workshop and soliciting suggestions for improvement. Sixty-three of 75 participants (84%) (postgraduate years 1-6) completed the exit questionnaire. Median rating of exercise usefulness on a scale of 1-10 ranged from 7.5 to 9. On a scale of 0-10, cumulative median scores of the course remained high over 4 years: time limit per station (9; interquartile range [IQR] 2), faculty instruction (9, IQR 2), ease of use (9, IQR 2), face validity (8, IQR 3), and overall course (9, IQR 2). On multivariate analysis, there was no difference in rating of domains between postgraduate years. Sixty-seven percent (42/63) believe that simulation training should be a requirement of Urology residency. Ninety-seven percent (63/65) viewed the laboratory as beneficial to their education. This workshop model is a valuable training experience for residents. Most participants believe that surgical simulation is beneficial and should be a requirement for Urology residency. High ratings of usefulness for each exercise demonstrated excellent face validity provided by the course.

MP51-06 ASSESSMENT OF FLEXIBLE URETEROSCOPIC STONE EXTRACTION SKILLS OF UROLOGY POSTGRADUATE TRAINEES DURING OBJECTIVE STRUCTURED CLINICAL EXAMINATIONS: IS THERE A PLACE FOR VIRTUAL REALITY SIMULATORS?

You have accessJournal of UrologySurgical Technology & Simulation: Training & Skills Assessment I1 Apr 2017MP51-06 ASSESSMENT OF FLEXIBLE URETEROSCOPIC STONE EXTRACTION SKILLS OF UROLOGY POSTGRADUATE TRAINEES DURING OBJECTIVE STRUCTURED CLINICAL EXAMINATIONS: IS THERE A PLACE FOR VIRTUAL REALITY SIMULATORS? Mehdi Aloosh, Félix Couture, and Sero Andonian Mehdi AlooshMehdi Aloosh More articles by this author , Félix CoutureFélix Couture More articles by this author , and Sero AndonianSero Andonian More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1615AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The first objective of this study was to assess whether UroMentorTM simulator could be used during an Objective Structured Clinical Examination (OSCE) to assess flexible ureteroscopic stone-extraction skills of urology postgraduate trainees (PGTs). The second objective was to determine whether previous experience in performing this task in the operating theatre or on the simulator correlated with performance during the OSCE. METHODS After obtaining ethics approval, PGTs from post-graduate years (PGY) 3 to 5 were recruited from all 4 Quebec urology training programs to participate in the study during an OSCE. After a short orientation to the UroMentorTM simulator (Simbionix, Cleveland, Ohio, USA), PGTs were asked to perform Task 10 for 15 minutes, where two small stones from the left proximal ureter and renal pelvis were extracted using a basket. Objective assessments from the simulator and subjective evaluations using the validated Ureteroscopy-Global Rating Scale (URS-GRS) tool were used to assess competency of PGTs in performing the task. Performance reports generated by the simulator and the URS-GRS scores were analyzed using paired t-test and Pearson correlation. RESULTS Out of thirty PGTs who participated in this study, 29 were right-handed. PGTs had performed a mean of 277.9 cystoscopies, 55.9 semirigid ureteroscopies, and 45.7 flexible ureteroscopies prior to the study. During the OSCE, mean URS-GRS score was 20.0 ± 4.4, mean operative time was 10.9 ± 2.1 minutes, mean fluoroscopy time was 7.0 ± 4.9 seconds, and mean number of traumas was 10.8 ± 3.8. Eight PGTs had practiced on the UroMentor simulator prior to the study with a mean URS-GRS score of 26.0 ± 7.2 on their last practice trial. At the OSCE, mean URS-GRS score of those who practiced on the simulator was significantly higher than the mean score of those who did not practice on the simulator (24.6 ± 3.0 vs. 18.3 ± 3.6, p<0.001). However, previous experience in the operating theatre and PGY level did not correlate with performance during the OSCE. CONCLUSIONS This study confirmed the feasibility of incorporating the UroMentor at OSCEs to assess competency of urology PGTs in ureteroscopic stone extraction skills. Moreover, PGTs who practiced on the simulator scored significantly higher than those who did not practice. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e695 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Mehdi Aloosh More articles by this author Félix Couture More articles by this author Sero Andonian More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Incidence and implications of silent hydronephrosis following percutaneous nephrolithotomy

While routine renal imaging following ureteroscopy for urinary calculi has been recommended to screen for asymptomatic "silent" obstruction, the rate of silent obstruction following percutaneous nephrolithotomy (PCNL) remains poorly defined, and no consensus recommendations exist on routine postoperative imaging. At our institution, we sought to assess the incidence of silent hydronephrosis (SH), as a screen for obstruction, following PCNL. The records of all 162 patients who met study inclusion criteria were reviewed. Of this group, 112 patients presented for their scheduled renal ultrasonography 4 - 6 weeks following stent removal to screen for SH. Asymptomatic patients found to have ultrasonographic evidence of hydronephrosis were further analyzed. SH was noted in 16% (18/112) of patients. Two required subsequent ureteroscopic stone extraction (1.8%), one of which also underwent endoureterotomy for a ureteral stricture. Four patients (22%) had stable hydronephrosis and declined functional imaging, 2 patients (11%) had a known partial ureteropelvic junction obstruction and declined intervention. SH resolved spontaneously in 50% (9/18) with a mean time to resolution of 6.3 months. There was no difference in stone complexity based on Guy's stone score between groups, 2.8 (±0.92) vs. 2.4 (±1.03), p=0.34. Although not statistically significant, patients with SH were more likely to have had residual stone fragments postoperatively, 39% (7/18) vs. 19% (18/94), p=0.067. SH following, PCNL was identified in 16% of this screened population, with the majority requiring no intervention. However, SH may be attributed to residual stone or stricture, which may have been otherwise unrecognized in up to 2% of patients undergoing PCNL. Consideration should be given for routine postoperative ultrasound to screen for silent obstruction following PCNL. .

Transfer of Flexible Ureteroscopic Stone-Extraction Skill from a Virtual Reality Simulator to the Operating Theatre: A Pilot Study

To assess the learning curve of flexible ureteroscopic stone extraction using the UroMentor™ simulator and transfer of flexible ureteroscopic stone extraction skills to the operating theatre. After obtaining ethics approval, urology Post-Graduate Trainees (PGTs) from Post-Graduate Years (PGYs) 1 to 4 were recruited. During phase I, participants completed 3 weekly 1-hour training sessions on the UroMentor simulator practicing task 10, where two stones from the left proximal ureter and renal pelvis were extracted using a basket. Objective assessments by the simulator and subjective assessments using the validated Ureteroscopy-Global Rating Scale (URS-GRS) were used to establish the learning curve. During phase II, the URS-GRS tool was used to assess performance of participants in the operating theatre. URS-GRS scores obtained on the simulator and in the operating theatre were correlated. In phase I, eight urology PGTs (PGY1-4) with mean age of 27.8 ± 2 (25-31) years participated in the study. PGTs practiced a total of 52 times, with a mean operative time of 14.6 ± 4.3 minutes and a mean fluoroscopy time of 10.4 ± 12 seconds. Competency in task 10 was achieved after seven trials on the UroMentor simulator. In phase II, 5 PGTs were assessed during 55 consecutive flexible ureteroscopic stone extraction in the operating theatre. The mean operative time was 51.4 ± 15.2 minutes and the mean fluoroscopy time was 29 ± 6 seconds. There was a significant positive correlation between URS-GRS scores obtained on the simulator and in the operating theatre (r = 0.9, p = 0.03), thus establishing predictive validity of performance on the UroMentor simulator. Competency in task 10 on the UroMentor simulator (flexible ureteroscopic stone extraction) was achieved after seven trials. Since there was a strong positive correlation between URS-GRS scores on the simulator and in the operating theatre, the skills obtained on the simulator could be transferred to the operating theatre.

Design of a new stone extraction device with force feedback

Ureteroscopic stone extraction devices are effective and ubiquitous tools in the management of urolithiasis. Ureteroscopy, however, has the potential to cause injury to the ureter. Perforation, and on some occasions, avulsion of the ureter as a result of excessive forces on the extraction device are some serious complications of this practice. In this paper, we propose the integration of a force sensor with stone extraction devices. The proposed prototype provides instantaneous force measurements imposed on the ureter wall during the stone removal procedure, and thereby, aids in reducing the risk of ureteral perforations and avulsions by highlighting the safety and hazardous extraction forces. A prototype was built and a bench top test was performed. The results obtained from the bench top tests were consistent with the results reported in previous works in the literature.

After urgent drainage of an obstructed kidney by internal ureteric stenting; is ureteroscopic stone extraction always needed?

ObjectivesTo assess the probability of spontaneous stone passage and its predictors after drainage of obstructed kidney by JJ stent, as insertion of an internal ureteric stent is often used for renal drainage in cases of calcular ureteric obstruction. Patients and methodsBetween January 2011 and June 2013, patients for whom emergent drainage by ureteric stents were identified. The patients’ demographics, presentation, and stone characteristics were reviewed. The primary endpoint for this study was stone-free status at the time of stent removal, where all patients underwent non-contrast spiral computed tomography (NCCT) before stent removal. Ureteroscopic stone extraction was performed for CT detectable ureteric stones at the time of stent removal. Potential factors affecting the need for ureteroscopic stone extraction at the time of stent removal were assessed using univariate and multivariate statistical analyses. ResultsEmergent ureteric stents were undertaken in 196 patients (112 males, 84 females) with a mean (SD) age of 53.7 (16.2) years, for renal obstruction drainage. At the time of stent removal, 83 patients (42.3%) were stone free; with the remaining 113 patients (57.7%) undergoing ureteroscopic stone extraction. On multivariate analysis, stone width [odds ratio (OR) 15.849, 95% confidence interval (CI) 2.83; P=0.002) and radio-opaque stones (OR 12.035, 95% CI 4.65; P<0.001) were independent predictors of the need for ureteroscopic stone extraction at the time of stent removal. ConclusionSpontaneous ureteric stone passage is possible after emergent drainage of an obstructed kidney by ureteric stenting. Stone opacity, larger stone width, and positive preoperative urine culture are associated with a greater probability of requiring ureteroscopic stone extraction after emergent drainage by ureteric stenting.

Significance of Extraction Forces in Kidney Stone Basketing.

Ureteroscopic stone extraction devices are effective tools in the management of urolithiasis, but on occasion, their improper use can cause injury to the ureter. Avulsion and perforation of the ureter as a result of excessive forces on the extraction device are some of the more serious complications of this treatment. In this article, avulsion and perforation forces were measured by two different test setups. Eleven clinicians were asked to apply three ranges of forces (safe, cautious, and dangerous). The output force measurements were recorded and plotted for further analysis. The maximal average perforation forces were 7.13±2.36 N in the benchtop tests and 7.07±2.20 N in the ex-vivo porcine tests (P=0.54). The maximal average avulsion forces were measured to be 10.14±2.01 N in the benchtop tests. Although the average forces were similar in the proximal and distal parts of the ureter (P=0.27), higher values were recorded for the distal part. The operative time was noted to be significantly different in the safe and cautious force regions (P=0.006). The average forces were higher in the benchtop tests compared with the porcine ureter tests. The extraction forces were measured and were noted to be significantly different for attending physicians and residents. The results suggest the need for force feedback training for residents. The findings can be used to design a "smart device" that can provide visual force feedback to clinicians while they are operating, leading to improved patient outcome.

Definitive ureteroscopy and intracorporeal lithotripsy in treatment of ureteral calculi during pregnancy

ObjectiveTo evaluate the outcome of using semi-rigid ureteroscopy with or without intracorporeal pneumatic lithotripsy vs. temporary ureteric JJ stenting in the management of obstructing ureteric calculi in pregnant women. Patients and methodsThis prospective comparative study comprised 43 pregnant women with obstructing ureteric calculi. The diagnosis was based on the acute flank pain as the main symptom, microscopic haematuria, and unilateral hydronephrosis on abdominal ultrasonography (US). The patients were randomly divided into two groups; those in group 1 (22 patients) were treated by temporary ureteric JJ stenting until after delivery, and those in group 2 (21) were treated definitively by ureteroscopic stone extraction with intracorporeal pneumatic lithotripsy. Postoperative complications and the degree of patient satisfaction were reported. ResultsAn obstructing ureteric stone was identified by US in 68% and 76% of groups 1 and 2, respectively. In group 1, nine patients had mid-ureteric stones and 13 had stones in the lower ureter. In group 2, seven patients had mid-ureteric stones, whilst the stones were in the distal ureter in 14. No perioperative foetal complications were detected in any group and all patients completed the full term of pregnancy. In group 1, four patients had a postoperative urinary tract infection (UTI), and the JJ stent was exchanged in seven. Two patients in group 2 had a postoperative UTI. ConclusionsDefinitive ureteroscopy, even with intracorporeal pneumatic lithotripsy, is an effective and safe treatment for pregnant women with obstructing ureteric calculi. It has a better outcome and is more satisfactory for the patients than a temporary JJ stent.

PD37-11 BLACK-STAR® - MAGNETIC DJ REMOVAL

You have accessJournal of UrologyStone Disease: New Technology II1 Apr 2014PD37-11 BLACK-STAR® - MAGNETIC DJ REMOVAL Marie-Claire Rassweiler, Maurice-Stephan Michel, and Manuel Ritter Marie-Claire RassweilerMarie-Claire Rassweiler More articles by this author , Maurice-Stephan MichelMaurice-Stephan Michel More articles by this author , and Manuel RitterManuel Ritter More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.2029AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Ureteral stenting is a common procedure in endourology. One routine indication is after ureteroscopic stone extraction if small urothelial lesions occured. The cystoscopic removal of a ureteral stent can cause unpleasant side effects, such as urinary frequency, urgency, incontinence, haematuria, bladder pain and flank pain, which have a negative impact on a patient's life. It is necessary to minimize the pain during stent removal in order to increase the patient’s quality of life. Therefore we prospectively assessed the feasibility of a newly developed ureter stent (DJ) with a small magnet at its distal end (Magnetic Black Star, Urotech (Achenmühle, Germany) and a customized magnetic retrieval catheter. METHODS The magnetic Blackstar DJ is a 7 french ureteral stent with a small magnet fixed with a string at the distal DJ loop. To remove the DJ a customized catheter with a magnetic Tiemann tip is used. The catheter is inserted after transurethral application of a standard lubricant and removed with the DJ after getting in contact with the DJ’s magnet. The study was approved by local ethics committee. We placed the magnetic DJ in 20 consecutive patients after ureteroscopy for stone removal. No additional foley catheter was placed. The DJ was removed the next day with the magnetic retrieval catheter either by a physician or a nurse. Retrieval time, patient comfort and feasibility of the retrieval device were assessed. RESULTS The DJ could be removed with the retrieval device within less than 30 seconds in 19 out of 20 patients. In the first patient the removal was not successful due to an enlarged prostate middle lobe. For this patient a cystoscopical removal was needed. In the second patient the removal was performed under fluoroscopic control to ensure save handling of the retrieval device by the surgeon. In all other patients the removal of the catheter was performed in the patients room on the ward. CONCLUSIONS The removal of the magnetic DJ using the retrieval device is fast and easy and can be performed by physicians as well as nurses. The patients didn’t complain about a lot of discomfort during the removal. This technique might lead to significant cost reduction compared to the standard cystoscopical removal of ureter stents with sterile instruments in the endourological operation room. Our feasibility study indicates this magnetic DJ to significantly reduce patient’s discomfort by DJ removal and therefore seems to be a promising new device for endourologists. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e949-e950 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Marie-Claire Rassweiler More articles by this author Maurice-Stephan Michel More articles by this author Manuel Ritter More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

C-reactive protein to predict the need for surgical intervention in acute renal colic

Objectives: C-reactive protein (CRP) is a serum marker of systemic inflammation which has been suggested to predict need for emergent surgical intervention in patients with acute renal colic at a value of &gt; 28 mg/l on admission.1 We aimed to determine if this applied to our patients. Patients and methods: We prospectively collected data from all patients admitted with symptomatic urolithiasis, confirmed by CT-KUB, over three months. Fifty-nine patients were included; however, four were excluded because of co-morbidites which could influence CRP, or recent urological surgery, giving N = 55, age 50.0±14.6 years (mean±SD), M:F 40:15. The decision to proceed to intervention was made by each patient’s clinical team and not by the authors; however, there was no blinding to CRP. Results: A total of 24 of 55 patients required intervention on their index admission (22 retrograde ureteric stent, one nephrostomy, one ureteroscopic stone extraction), and 31 were managed conservatively. Those undergoing intervention had higher CRP on admission (mean 16.3 vs 9.4 mg/l, p = 0.06) and higher maximum CRP (mean 94.7 vs 25.7 mg/l, p &lt; 0.001) than those managed conservatively. Nineteen (79%) of those requiring intervention had CRP &lt; 28 mg/l on admission. There were no deaths, no intensive care admissions and all were discharged to outpatient follow-up. Conclusion: Rising CRP during admission is a strong predictor of the need for emergency surgical intervention in patients with acute renal colic; however, CRP at admission is less useful.

A Prospective Evaluation of Pain Associated With Stone Passage, Stents, and Stent Removal Using a Visual Analog Scale

To investigate the perception of colicky pain due to ureteral stones and double-J (DJ)-associated discomfort and to evaluate the role of clinical parameters that might influence the perception of pain. From November 2011 to May 2012, 124 consecutive patients with colicky pain due to ureteral stones and ureteroscopic stone extraction underwent DJ stent placement. A visual analog scale (VAS) was used to assess the pain at ureteral colic, during indwelling DJ stent, and at DJ stent removal. The association of clinical data with pain scores was also analyzed. Pain perception at the time of colic did not vary according to sex (P = .804), age (P = .674), or DJ stent length (P = .389). Stone size (<4 mm) was a predictor of a high VAS score (P = .001). Patients with recurrent stone formation had significantly less pain at the time of colic (P = .004), and DJ stent removal (P = .004) than those with the first instance of stone formation. The clinical experience at cystoscopic DJ stent removal influenced pain perception (P <.001). Using a VAS for the evaluation of pain perception is a valid method for the objectification of subjective discomfort. The VAS is an easy to administer scale and provides accurate information on the patients' status. Additional studies with larger cohorts focusing on pain perception using the VAS and other validated questionnaires are recommended to produce more consistent data.

Strahlenbelastung der Patienten bei der ureterorenoskopischen Steinentfernung

We determined the intraoperative patient radiation exposure during ureteroscopic extraction of ureteral or renal stones. The investigation was carried out in 215 patients who underwent ureteroscopy for ureteral or renal stone extraction. Radiation exposure was measured as dose-area product (DAP) within the X-ray beam. The effective abdominal dose was calculated using the specific conversion factor of 0.00323 mSv/µGy×m². Depending on the stone location (i.e. ureter or kidney), the type of ureteroscopy (i.e. semirigid or flexible) and type of stone removal (i.e. simple stone extraction or intracorporeal laser lithotripsy), the intraoperative patient radiation exposure (effective dose ED) ranged from 0.67 mSv (DAP 221.9 µGy×m²) to 2.23 mSv (DAP 744.2 µGy×m²). Patient radiation exposure during ureteroscopic stone extraction is comparable to patient radiation exposure using plain film urography or low-dose non-contrast-enhanced computed tomography for diagnosis of urolithiasis.

UP-03.078 An Alternative Method in Ureteroscopic Extraction of Ureteral Stones

Ureteroscopic stone extraction has been considered as an efficacious method especially for retrieval of lower ureter stones. Herein, we would like to present an easier and safe method for extraction of fragmented remnant stones through the intravesical ureter.

Comparison of Extracorporeal Shock Wave Lithotripsy Versus Ureteroscopic Stone Extraction in the Treatment of Ureteral Stones

Aim: There are some controversies on the effectiveness of extracorporeal shock wave lithotripsy (ESWL) and ureteroscopic stone extraction (URS) in ureteral stones. Because, previous studies on this topic mostly included lower ureteral stones, we aimed to compare effectiveness of these two methods in both lower and upper ureteral stones. Method: After diagnosis of urolithiasis, ESWL or URS was performed to patients. Stone-free ratio, complications and necessity of an additional intervention for both procedures were recorded. The decision about the selection of method was made based on the patients’ choice. Upper and lower ureteral stones were included, while middle ureteral stones were excluded from the study. Result: Total number of patients undergone URS was 90 and ESWL was 96. There was no difference in male/female ratio, age and stone diameters between two groups (P>0.05). Upper ureteral stones were found to be more frequent in ESWL group than those in URS group (55.2% vs. 33.3%, respectively, P=0.004). Total stone-free ratio was 97.8% for URS and 68.8% for ESWL (P<0.001). Ratios of treatment failures and complications were found to be lower in URS group compared with ESWL group (P<0.05). Conclusion: Although, URS seems to be more successful in the treatment of ureteral stones, further prospective studies with more patients are needed to clarify our results.