Ureteral Stent Insertion Research Articles

Ureteric stenting outside of the operation theatre: challenges and opportunities.

To evaluate the safety, efficacy, tolerability, and cost-effectiveness of bedside or office-based ureteric stent insertion. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Protocols (PRISMA-P) and A MeaSurement Tool to Assess systematic Reviews (AMSTAR) 2 guidelines, we searched PubMed/the Medical Literature Analysis and Retrieval System Online (MEDLINE), the Excerpta Medica dataBASE (EMBASE), Google Scholar, Cochrane Central Register of Controlled Trials (CENTRAL), and Dimensions for English-language studies from 1978 to April 2023. Inclusion criteria focused on primary ureteric stent placements outside of the operating theatre (OT). A total of 15 studies involving 2072 stents were included. Success rates for correctly positioned stents in bedside or office-based insertions ranged from 60% to 95.8%, with most studies reporting ≥80% success rates. Common failure reasons included impacted stones and difficulty identifying the ureteric orifice. Pain and tolerability were assessed using various methods, with validated tools indicating moderate pain levels, but most patients would undergo the procedure again under local anaesthesia. Complication rates were generally low, with minor complications such as haematuria or postoperative fever being the most common. Procedural costs were significantly lower in non-OT settings, with estimates indicating savings of up to four-fold. Bedside or office-based ureteric stent insertion is a viable alternative to OT procedures, offering high success rates, manageable pain levels, low complication rates, and substantial cost savings. This approach is particularly advantageous in settings with limited OT access, highlighting its potential for broader adoption in urological practice. Future research should focus on standardising pain assessment methods and randomised studies.

A case report of retroperitoneal liposarcoma.

Retroperitoneal liposarcoma is a rare and complex tumor originating from the mesenchymal tissues, with no specific manifestations in the early stage, and a large tumor size in the late stage. Patients often consult a physician because of large abdominal mass, increased abdominal circumference, and abdominal pain, and rarely because of leukocytosis. A 54-year-old female presented to our hospital with complaints of "abdominal distension for over 3 months, left lumbar pain for over 2 months." Considering the comprehensive symptoms, examinations, computed tomography scans, and pathological results, the possibility of retroperitoneal liposarcoma is high. Retroperitoneal liposarcoma with leukocytosis. Open retroperitoneal mass excision along with transcystoscopic left ureteral Double-J Ureterl Stent Insertion tube placement and left nephrectomy. The postoperative pathological findings of the abdominal mass, combined with morphological and immunohistochemical results, are consistent with retroperitoneal liposarcoma. The patient had no recurrence in 7 months of postoperative follow-up conducted on the telephone and is now in continued follow-up. Retroperitoneal liposarcoma is highly malignant and prone to recurrence. Radical surgery is currently the primary treatment modality for patients with this condition. Analogous to cancer patients, those with elevated white blood cell counts and retroperitoneal liposarcoma may have poor prognoses, with a high likelihood of local recurrence and distant metastasis. Close postoperative follow-up is necessary. Therefore, regular postoperative review of blood routine may be a relatively economical and convenient method for the early detection of recurrence and metastasis of retroperitoneal liposarcoma.

Audit of the Acute Management of Renal Colic in District Hospitals Within a National Health Service Trust.

Renal colic is a prevalent acute urological emergency caused by urinary stones and commonly manifests as severe loin pain. This audit assesses the management of acute renal colic at a National Health Service (NHS) Trust in the West Midlands, England, comparing practices against theNational Institute for Clinical Excellence (NICE) and the British Association of Urological Surgeons (BAUS) guidelines. This retrospective audit reviewed 417 patients with suspected renal colic over a month. Data collected included patients' demographics, time to complete CT scan, laboratory investigations requested and management modalities. Patients assessed were either admitted through the Emergency Department, Surgical Assessment Unit, or previously admitted for other conditions on the wards. The audit benchmarked against NICE and BAUS guidelines, focusing on diagnostic timeliness and management, including essential blood investigations. Data analysis performed using SPSS (IBM Corp., Armonk, NY, USA) included descriptive statistics and Chi-square tests, with significance set at p < 0.05. A total of 417 patients met the inclusion criteria. The average age of patients was 47.4 years with slightly higher male population (51.1%). The diagnostic rate for renal or ureteric stones using computed tomography of the kidneys, ureters, and bladder (CT-KUB) was 41.2%. The positive detection rate was significantly higher in males (54%) compared to females (27.5%) while females have more alternate diagnosis than males (13.7% vs 6.1%). The average completion time of CT-KUB was nine hours with 7.7% of patients having their CT-KUB beyond the 24-hour benchmark. Most patients (48%) were managed conservatively with analgesia, 32% received tamsulosin as medical expulsive therapy and others had interventions like ureteric stent insertion (9.3%), nephrostomy (6.4%) or primary ureteroscopy (4.1%). The audit of renal colic management at our centre revealed a 41.2% diagnostic rate for renal or ureteric stones via CT-KUB, with a significantly higher rate in males than females. Diagnostic delays were minimal, with only 7.7% of scans exceeding 24 hours. Conservative management was common, however non-steroidal anti-inflammatory drugs (NSAIDs) were underutilized despite guideline recommendations. There was a notable gender disparity in diagnostic and alternate findings rates. The results showed the need for adherence to pain management protocols and highlight the effectiveness of existing renal colic protocol, while also pointing to potential areas for improvement in treatment uniformity and guideline adherence.

Human in vivo baseline intrarenal pressure, peristaltic activity and response to ureteric stenting.

To assess human in vivo intrarenal pressure (IRP) and peristaltic activity at baseline and after ureteric stent placement, using a narrow calibre pressure guidewire placed retrogradely in the renal pelvis. A prospective, multi-institutional study recruiting consenting patients undergoing ureteroscopy was designed with ethical approval. Prior to ureteroscopy, the urinary bladder was emptied and the COMET™ II pressure guidewire (Boston Scientific) was advanced retrogradely via the ureteric orifice to the renal pelvis. Baseline IRPs were recorded for 1-2 min. At procedure completion, following ureteric stent insertion, IRPs were recorded for another 1-2 min. Statistical analysis of mean baseline IRP, peristaltic waveforms and frequency of peristaltic contractions was performed, thereby analysing the influence of patient variables and ureteric stenting. A total of 100 patients were included. Baseline mean (±SD) IRP was 16.76 (6.4) mmHg in the renal pelvis, with maximum peristaltic IRP peaks reaching a mean (SD) of 25.75 (17.9) mmHg. Peristaltic activity generally occurred in a rhythmic, coordinated fashion, with a mean (SD) interval of 5.63 (3.08) s between peaks. On univariate analysis, higher baseline IRP was observed with male sex, preoperative hydronephrosis, and preoperative ureteric stenting. On linear regression, male sex was no longer statistically significant, whilst the latter two variables remained significant (P = 0.004; P < 0.001). The mean (SD) baseline IRP in the non-hydronephrotic, unstented cohort was 14.19 (4.39) mmHg. Age, α-blockers and calcium channel blockers did not significantly influence IRP, and no measured variables influenced peristaltic activity. Immediately after ureteric stent insertion, IRP decreased (mean [SD] 15.18 [5.28] vs 16.76 [6.4] mmHg, P = 0.004), whilst peristaltic activity was maintained. Human in vivo mean (SD) baseline IRP is 14.19 (4.39) mmHg in normal kidneys and increases with both hydronephrosis and preoperative ureteric stenting. Mean (SD) peristaltic peak IRP values of 25.75 (17.9) mmHg are reached in the renal pelvis every 3-7 s and maintained in the early post-stent period.

Safety and efficacy of ultrasound-assisted bedside ureteric stent placement A prospective, single-institution study.

Previous studies have demonstrated the feasibility of bedside placement of ureteric stents; however, they have traditionally required two skilled operators and were associated with some stent malposition especially for proximal ureteric obstruction. We sought to investigate the efficacy and safety of a modified technique for ultrasound-assisted bedside ureteric stent insertion without the presence of a skilled assist. A single institution prospective study was performed from April-August 2023. Indications for stenting included infection, renal insufficiency, or intractable colic. Exclusion criteria included age <18 years, hemodynamic instability, and patients with history of chronic pain. Point-of-care ultrasound (POCUS) was used to confirm wire placement in the kidney and presence of a hydronephrotic drip from a 5 French ureteric catheter was used to confirm placement beyond the level of obstruction. Of 28 patients, all patients underwent successful bedside ureteric stent placement. Mean age was 64.9 years and mean body mass index (BMI) was 33.2. Proximal ureter obstruction was present in 52% of patients and mid/distal obstruction in 48%. In cases with obstructing stones, the mean stone size was 8.1 mm with a range of 4-15 mm. Infection was the indication for stent placement in most patients (71%), followed by pain (4%) and acute kidney injury (AKI) (4%). All patients who underwent successful stent placement had presence of hydronephrotic drip from the ureteric catheter. Ultrasound-assisted bedside ureteric stent insertion without a skilled assist is a safe and feasible option for management of acute ureteral obstruction. Presence of hydronephrotic drip can indicate successful access beyond the level of obstruction as an alternative to POCUS.

657 Transplant Ureteric Stent Removal Using Isiris® in an Outpatient Setting

Abstract Aim The risk of urological complications following kidney transplantation is reduced by the intraoperative insertion of ureteric stents. Transplant ureteric stent removal (TUSR) has traditionally been performed in theatre using flexible cystoscopy. Isiris® is a single-use flexible cystoscope. The aim is to analyse the acceptability, efficacy, and cost-effectiveness of Isiris®, for TUSR in a ward/outpatient setting. Method A retrospective analysis of a contemporaneously maintained database at a high-volume kidney transplant centre from January 2021 to June 2022. Data collected included clinico-demographic, operative and stent removal details including time to removal (gold-standard within 6 weeks) and refusal rates. A cost analysis was also performed based on equipment costs and NHS tariffs. TUSR was performed using Isiris® in outpatient ANP-led clinics or on wards by surgical middle grades or ANPs. Results 345 patients were included in analysis with a median age of 54 (19-81). 99.13% were single ureteric anastamoses with 348 stents removed in total. The M:F ratio was 1.32:1. 98.85% of stents were removed using Isiris®, with a 1.15% refusal rate. 86.34% (n=297) were removed in clinic. Median dwell-time was 34 days, IQR 17.25 (25.75-43). 73.84% of stent removal was within 6 weeks. There were savings of £545.00 per stent removal, including expenses for failed Isiris TUSR, with overall savings of £154,021.20 and 86 theatre sessions freed for other activity. Conclusions Isiris® was acceptable and effective for TUSR. Savings were demonstrated compared to TUSR in theatre. Outpatient/ward TUSR reduces demand for theatre time, freeing theatres for other elective activities.

From Routine to Exceptional: Exploration of a Unique Case of Bilateral Renal Parenchymal Perforation and Unilateral Hematoma Formation after Double J Ureteral Stent Insertion

From Routine to Exceptional: Exploration of a Unique Case of Bilateral Renal Parenchymal Perforation and Unilateral Hematoma Formation after Double J Ureteral Stent Insertion

UO-YOLO: Ureteral Orifice Detection Network Based on YOLO and Biformer Attention Mechanism

Background and Purpose: In urological surgery, accurate localization of the ureteral orifice is crucial for procedures such as ureteral stent insertion, assessment of ureteral orifice lesions, and prostate tumor resection. Consequently, we have developed and validated a computer-assisted ureteral orifice detection system that combines the YOLO deep convolutional neural network and the attention mechanism. Data: The cases were partitioned into a training set and a validation set at a 4:1 ratio, with 84 cases comprising 820 images in the training set and 20 cases containing 223 images in the validation set. Method: We improved the YOLO network structure to accomplish the detection task. Based on the one-stage strategy, we replaced the backbone of YOLOv5 with a structure composed of ConvNeXt blocks. Additionally, we introduced GRN (Global Response Normalization) modules and SE blocks into the blocks to enhance deep feature diversity. In the feature enhancement section, we incorporated the BiFormer attention structure, which provides long-distance context dependencies without adding excessive computational costs. Finally, we improved the prediction box loss function to WIoU (Wise-IoU), enhancing the accuracy of the prediction boxes. Results: Testing on 223 cystoscopy images demonstrated a precision of 0.928 and recall of 0.756 for our proposed ureteral orifice detection network. With an overlap threshold of 0.5, the mAP of our proposed image detection system reached 0.896. The entire model achieved a single-frame detection speed of 5.7 ms on the platform, with a frame rate of 175FPS. Conclusion: We have enhanced a deep learning framework based on the one-stage YOLO strategy, suitable for real-time detection of the ureteral orifice in endoscopic scenarios. The system simultaneously maintains high accuracy and good real-time performance. This method holds substantial potential as an excellent learning and feedback system for trainees and new urologists in clinical settings.

MAGnetic REtriaval Device for Minimally Invasive Ureter Stent Removal.

Purpose: To assess the effectiveness and pain intensity associated with magnetic ureteral stent removal using a retriever, without the aid of ultrasound guidance. Methods: We prospectively enrolled 100 patients who underwent retrograde rigid and flexible ureterorenoscopy with or without laser lithotripsy for ureteronephrolithiasis treatment from September 2021 to June 2023. These patients were assigned in two groups. Group 1 underwent the traditional ureteral stent insertion, while Group 2 underwent magnetic ureteral stent insertion. Both insertion and removal times were documented. The indwelling time for ureteral stents was 14 days. One group underwent stent removal via flexible cystoscopy using grasping forceps and the other group using just a magnetic retriever, without the aid of ultrasound guidance. The numeric pain rating scale, recommendation rate, and a standardized self-answered ureter stent symptoms questionnaire (USSQ) were obtained directly after stent removal. Results: Both groups presented comparable characteristics in factors such as age, body mass index, history of stone treatments, procedure type, and complication rates during and post-surgery. Time taken for ureteral stent insertion did not differ significantly between the groups (131.2 seconds for Group 1 vs 159.1 seconds for Group 2). However, the stent removal time (152.1 seconds for Group 1 vs 35.4 seconds for Group 2) and pain intensity (6 for Group 1 vs 2 for Group 2) were significantly lower for Group 2. Furthermore, five out of the six sections of the USSQ showed significantly better results for Group 2. Conclusions: The use of magnetic ureteral stents, as a safe and efficient alternative to conventional ureteral stents, not only eliminates the need for cystoscopy but also conserves resources and reduces patient discomfort.

Association between material and design used in a ureteral stent with complication in ureteral catheterisation: A systematic review

The double-J stent is one of the ureteral catheters with curved ends for fixation. Since its introduction in 1978, catheterisation using a double-J stent has become one of the most frequently performed procedures in urology. However, double-J stents may lead to various complications, causing patient discomfort, pain, and bladder symptoms. Technological advancements in stent design aim to minimise these complications and enhance comfort. This review aimed to determine the association between the material and design used in ureteral stents and complications in ureteral catheterisation. We conducted a systematic review following the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) checklist. Screening based on specific inclusion criteria was employed to select potential studies. A database search yielded a total of 124 studies. Nine full texts were evaluated for eligibility, resulting in the exclusion of one paper. Our findings indicate that ureteral stent insertion significantly increases the frequency of pain and urinary symptoms while decreasing overall health. The choice of materials and design plays a crucial role in minimising pain and improving the quality of life for patients. Physical properties such as firmness and tensile strength also affect the quality of life, with higher firmness and tensile strength causing lower quality of life. Stent material and design choice were context-dependent. Using soft stents and specialised soft distal pigtails has been shown to reduce patient stent-related symptoms. Silicone stents showed the least bladder symptoms than polymeric stents. Polymeric stents also showed no difference in utility from metallic stents for long-term usage.

Effect of theophylline on stent-related symptoms in patients undergoing Double-J ureteral stent insertion: a randomized controlled trial.

To investigate the effect of oral theophylline on stent-related syndrome (SRS) after Double-J insertion. Double-J stent is widely using in many urological procedures. Infection, hematuria, and discomfort are some of common complication after stenting. Theophylline is a dimethylated xanthine that inhibits phosphodiesterase and blocks adenosine receptors. To relaxing effect of theophylline on smooth muscles and its effects on the urinary system, it seems it could reduce complications after inserting Double-J stent especially ureteral stent syndrome. In this double-blind placebo-controlled randomized clinical trial, 67 patients were enrolled. Mean (SD) age of control and theophylline group was 51.8 (12.5) and 43.9 (10.4) years old, respectively. Patients were randomized into two groups of control and theophylline. All patients were stenting with silicon Double J. Theophylline group received 100mg of theophylline, twice daily for 30days, while control group received placebo. Stent symptoms were assessed by questionnaire and urine culture was performed before stent removal at removal day. Statistical analysis was performed using Chi-squared test and t test with P < 0.05 considered significant. Logistic regression models were fitted, crudely and adjusted for age and sex. Of 67 eligible patients, 60 completed the study. Theophylline significantly decreased percentages of gross hematuria (P < 0.001), dysuria (P < 0.001), and urinary frequency (P < 0.001). Microscopic hematuria (P = 0.042) and chills (P = 0.042) also decreased after theophylline. Theophylline could be an effective and safe choice for reducing SRS among patients undergoing Double-J stent insertion.

Ocular radiation exposure is negligible in normal volume endourological practice.

The annual dose limit for radiation exposure to the eye has been reduced recently; the eye is widely recognised as one of the most radiosensitive tissues in the body. There is minimal good quality research as to the radiation dose that the eye receives during endourological surgery and this study aimed to address this. A prospective study was performed over an 8-month period at a single large teaching hospital in the UK. Three index procedures were included: ureteric stent insertion, ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL). Surgeons wore a dosimeter on the glabella with fluoroscopy time (FT) and dose area product (DAP) recorded for each case. A total of 404 procedures were included (247 URSs, 150 ureteric stent insertions and 7 PCNLs). Dosimeters were worn by ten surgeons. Mean FTs (URS 20.56s; ureteric stent 18.96s; PCNL 360.67s) and mean DAP (URS 100.82cGy/m2, ureteric stent 119.82cGy/m2 and PCNL 1121.62cGy/m2) were identified with significant intersurgeon variability. No surgeon had a total dosimeter dose >0.00mSv. The International Commission on Radiological Protection recently reduced the yearly eye dose limit from 150 to 20mSv. Cataractogenesis is no longer considered a typical deterministic effect, with a threshold level below which no effect occurs. Even in higher volume centres, these annual limits are unlikely to be reached. Lead glasses may be considered for surgeons and radiologists with the highest exposure but, for the majority, ocular radiation exposure is negligible.

Ureteral stent related symptoms: A comparative study.

In urology, ureteral stents are used to treat obstructive diseases. Hematuria (54%), fever, discomfort, and lower urinary system symptoms are the predominant symptoms related to ureteral stent. This article links stent symptoms to double-j width and length, as well as patient's height, weight, and body mass index (BMI). Ureteric Stent Symptoms Questionnaire (USSQ) was used to measure ureteral stent symptoms at 1st and 4th week of stent in situ as well as the 4th week after pigtail removal. A 200-patient prospective study, where patients were allocated into four groups following ureteral stent insertion depending on the stent characteristics. Those groups were: 4.8 Fr./26 cm (Group A), 4.8 Fr./28 cm (Group B), 6 Fr/26 cm (Group C), and 6 Fr/28 cm (Group D). Men comprised 53.5% of 200 patients. Participants had an average age of 49 ± 15.5 years, height of 175 ± 8.94 cm, and BMI of 23.8 ± 7.6 cm. The laboratory results were identical between groups. At the first and fourth week, groups had similar urine symptoms, pain severity, health status and occupational activities. The difference in pain location was statistically significant. Group A had 82.4% renal back pain in the first week, whereas Group B had 68.8%, Group C 31.3% and Group D 62.5 (p = 0.04). At the fourth week, 64.7% of Group A patients reported kidney front pain, compared to 100% of Group B, 93.3% of Group C, and 100% of Group D (p = 0.04). There was statistical significance in the sexual activity of the patients. 24.4% of Group C patients stopped sexual activity before stent installation, compared to 10.6%, 8.3%, and 6.4% of the other groups (p = 0.03). A moderate percentage of patients had active sexual activity at week 4 (Group A: 7.8%, Group B: 5.8%, Group C: 8.2%, Group D: 4.1%), p = 0.83. In multivariate analysis, urinary catheter group, age, weight, height, and BMI did not significantly affect urine index score (UIS), pain index score (PIS), general health (GH), quality of work (QW), and quality of sex (QS). Despite various attempts to establish the best ureteral stent, the effect of double-j stent physical features on stent-related symptoms remained unknown. No verdict is conceivable without adequate empirical data.

Urology never events in the United Kingdom: A retrospective 10‐year review

AbstractObjectivesThe aim was to assess the prevalence of never events (NEs) specific to urology in the United Kingdom and identify commonly occurring themes.MethodsData from the National Health Service (NHS) NEs website were obtained and all NEs from 2012 to 2022 were reviewed. Urology‐specific NEs were identified and further analysed in their respective categories. Data regarding the total number of surgical procedures performed in the NHS specific to each specialty were obtained via the NHS Hospital Episode Statistics website.ResultsThere were 3972 NEs recorded over the 10‐year period with 95 (2.4%) of these as a result of urology surgery. The most common surgical intervention associated with a urological NE was ureteric stenting, which comprised 45/95 (47.4%) of all analysed NEs. These consisted of wrong site ureteric stent insertion (n = 29), wrong site ureteric stent removal (n = 9), wrong stent type (n = 5) and retained guidewires (n = 2). There were 7.14 million urology surgeries performed in the 10‐year period, and prevalence was 0.0013%.ConclusionNEs are fully preventable serious incidents in the NHS. This is the first study to investigate the prevalence of NEs in urology in the United Kingdom. This study demonstrates that in the last 10 years the prevalence of urology NEs is low at 0.0013%, with ureteric stent procedures accounting for more than half of the NEs. Urologists should be mindful of the potential for wrong site surgery in urologic stenting procedures.

The Management of Symptomatic Hydronephrosis in Pregnancy.

The aim of this article is to provide a literature review on the management of symptomatic physiological hydronephrosis in pregnancy and compare different modalities of intervention when needed. In this review, we conducted an electronic literature search of peer-reviewed journal articles. The PubMed, Research Gate, and Google Scholar databases were queried with the following search terms: "pregnancy", "obstruction," and "hydronephrosis"; the terms "urolithiasis" and "kidney stone" were excluded. As a result, conservative treatment was successful and more favored for most of the patients and the clinicians in the different studies we found. Conservative management will usually include regular analgesia, positioning, and antibiotics. Close follow-up with ultrasound is always recommended. Intervention with ureteric stent insertion or nephrostomy tube insertion was less favored and only triggered by certain clinical criteria. In conclusion, symptomatic hydronephrosis in pregnancy can be safely treated conservatively. However, ureteral double-J stenting or percutaneous nephrostomy are effective and safe treatment methods in the minority of patients with persistent symptoms not responding to conservative management.

Percutaneous Ureteral Stent Insertion in Patients with Benign Uretero-Ileal Anastomosis Strictures Who Underwent Radical Cystectomy: Assessing Risk Factors for Stent Patency.

We aimed to investigate the risk factors of early double-J ureteral stent (DJUS) dysfunction rates and the long-term patency of DJUSs inserted via a percutaneous approach in patients with benign uretero-ileal anastomosis stricture (UIAS) who had undergone radical cystectomy. In this retrospective study, 63 DJUS placements were placed via a percutaneous nephrostomy tract in 42 consecutive patients between May 2020 and March 2023. The technical success rate was 100% in all patients without major complications. The early dysfunction rate and long-term patency rate were 38.1% (24/63) and 84.2% (32/38), respectively. The blood clot retention grade, balloon dilatation, and length of the ureteral stricture exhibited a significant correlation with early DJUS dysfunction (blood clot retention grade: odds ratio (OR) 6.922 in grade two, p = 0.009; balloon dilatation: OR 0.186, p = 0.017; length of ureteral stricture: OR 8.715, p = 0.035 in moderate stenosis, and 7.646, p = 0.028 in severe stenosis). A multivariate Cox's proportional hazard analysis revealed that blood clot retention grade and length of ureteral stricture were independent predictors of long-term DJUS patency. Percutaneous insertion of the DJUSs was safe and effective in patients with benign UIAS.

Effect of co-trimoxazole and N-acetylcysteine alone and in combination on bacterial adherence on ureteral stent surface

To assess the effect of co-trimoxazole and N-acetylcysteine (NAC), alone and in combination, on bacterial adherence to biofilm formed on ureteral stent surfaces. This prospective randomized study was conducted on 636 patients who underwent double J ureteral stent insertion after variable urological procedures. Patients were randomized into four groups: A (n = 165), no antibiotics or mucolytics during stent indwelling; B (n = 153), oral NAC (200 mg/day for children aged < 12 years old and 600 mg/day for adults) during stent indwelling; C (n = 162), oral co-trimoxazole (2 mg TMP/kg/day) during stent indwelling; and D (n = 156), both oral NAC and co-trimoxazole during stent indwelling. Two weeks following double J stent (JJ stent) insertion, urinalysis was performed on all patients and urine culture was done for all the patients at the day of double J stent removal. The stent was removed 2 weeks postoperatively, and a stent segment sized 3–5 cm from the bladder segment of the stent was sent for culture. Positive stent cultures were found in 63.6% (105/165), 43.1% (66/153), 37% (60/162), and 19.2% (30/156) patients of groups A, B, C, and D, respectively. E. coli was the organism most commonly isolated from the stent culture in all groups. The combination of co-trimoxazole and NAC was more effective in reducing bacterial adherence on ureteral stent surfaces than either alone.

Comparison Between Tamsulosin and Oxybutynin in Relieving Ureteral Stent Related Symptoms

One handred cases with unilateral ureteral stent insertion were randomized into four groups; given placebo (25 patients), Oxybutynin 5mg once daily (25 patients), Tamsulosin 0.4mg once daily (25 patients) or combination respectively. All patients received the drugs for three weeks and completed the symptom questionnaire and quality of life questionnaire one week after stent insertion and one week after stent removal. There was no significant difference in the efficacy between Tamsulosin and Oxybutynin in relieving urgency (9 patients, 9 patients respectively), frequency (7 patients, 9 patients respectively) and dysuria (11 patients, 9 patients respectively) with the superiority of combination therapy (12 patients, 16 patients, 17 patients respectively)( P-values: 0.01, 0.001, 0.001 respectively). For relieving abdominal pain, Tamsulosin was more efficacious than Oxybutynin (8 patients versus 5 patients) with the superiority of the combination therapy (12 patients) (P-value: 0.001). For relieving hematuria, Tamsulosin and combination therapy were comparable and both superior to Oxybutynin with a P-value 0.001. For improving quality of life, both Tamsulosin and Oxybutynin were comparable (9 patients, 9 patients) with superiority of combination therapy (15 patients) with a P-value 0.001.

The Consecutive 200 Cases of Endoscopic-Combined Intrarenal Surgery: Comparison between Standard and Miniature Surgeries.

Background and Objectives: Percutaneous nephrolithotomy (PCNL) is still the gold-standard treatment for large and/or complex renal stones. Endoscopic combined intrarenal surgery (ECIRS) was developed with the goal of minimizing the number of access tracts of PCNL while simultaneously improving the one-step stone-free rate (SFR). The aim of this study was to share the experience of the consecutive 200 cases of ECIRS in one institute and analyze surgical outcomes of mini-ECIRS and standard ECIRS. Materials and Methods: We performed ECIRS for 200 adult patients between July 2017 and January 2020. An ECIRS was performed with the patient under general anesthesia in the intermediate-supine position. Surgeries were finished using a tubeless technique with a simple ureteral stent insertion. Results: There were significant differences in the mean maximal stone length (MSL), the variation coefficient of stone density (VCSD), the linear calculus density (LCD), the Seoul National University Renal Stone Complexity (S-ReSC), and the modified S-ReSC scores in stone characteristics, and estimated blood loss (EBL) and operation time in peri-operative outcomes between conventional and mini-ECIRS. After propensity-score matching, there was only a difference in EBL between the two groups. In logistic regression models, MSL [odds ratio (OR) 0.953; 95% confidence interval (CI) 0.926-0.979; p < 0.001], LCD (OR 4.702; 95% CI 1.613-18.655; p = 0.013) were significant factors for the success rate after ECIRS. Conclusions: In patients who underwent a mini-ECIRS, the stones were relatively smaller and less complex, and the operation time was shorter. However, if the size of stones was similar, there was no difference in the success rate, but EBL was lower in mini-ECIRS than in standard surgery.

The optimal stent pusher position to achieve successful ureteral stent insertion under fluoroscopic guidance

To examine factors to predict the optimal stent pusher position when inserting ureteral stents under fluoroscopy. We retrospectively reviewed 327 patients who underwent ureteral stent insertion. We considered the pubic bone as a useful anatomical landmark to insert ureteral stents under fluoroscopic guidance. Thus, we categorized patients into three groups (proximal, middle, and distal groups) according to the position of the radiopaque tip of the push catheter when inserting the ureteral stent. Success was defined as a completely curled ureteral stent tail. We compared stent insertion success rates among the three groups. A multivariate analysis was performed to identify the factors affecting stent insertion success. In men, 36 (63.2%) cases were deemed successful in the proximal group compared with 40 (80.0%) cases in the middle group and 12 (20.7%) cases in the distal group (p<0.001). In women, 26 (45.6%) cases were deemed successful in the proximal group compared with 54 (98.2%) cases in the middle group and 38 (76.0%) cases in the distal group (p<0.001). With the multivariate analysis, the stent pusher position was the most significant factor influencing successful stent insertion (men: odds ratio 6.00, 95% confidence interval 2.66-13.51, p<0.001; women: odds ratio 37.80, 95% confidence interval 4.94-289.22, p<0.001). The position of the stent pusher affects stent insertion success. The middle of the pubic symphysis is the optimal position for the radiopaque tip of the pusher when inserting ureteral stents under fluoroscopic guidance.