Outcomes of a non-randomised audit of single pigtail suture stents in urolithiasis management of Asian patients in Singapore

Objective

Double-J (DJ) ureteric stents are commonly placed perioperatively for semirigid or flexible ureteroscopic renal surgery. It is believed that lesser stent material within the bladder mitigates stent-related symptoms. This study aimed to evaluate the J-Fil ureteral stent, a single pigtail suture stent compared with conventional DJ stent in relation to stent symptoms in an Asian population undergoing ureterorenal intervention.

Methods

Based on internal audit committee recommendation approval, the records of 50 patients retrieved, available data of 41 patients who were prospectively enrolled into two groups (Group 1 [J-Fil stent group], n=21 and Group 2 [DJ stent group], n=20) between August 2020 to January 2021, were analysed. Parameters compared were nature of procedure, stone location and size, ease of deployment or removal, and complications. A modified universal stent symptom questionnaire was used to assess morbidity of stent symptoms within 48 h of insertion and at removal.

Results

Both groups had similar median age, distribution in male to female ratio, and stone size. The overall median universal stent symptom questionnaire score at insertion was similar for bladder pain, flank or loin pain, and quality of life between Group 1 and 2; however, at removal Group 1 fared significantly better than Group 2, especially for flank or loin pain and pain at voiding. Both groups had similar ease in insertion with no hospital readmissions.

Conclusion

Our audit favoured the single pigtail suture stent in Asian ureters in mitigating stent-related issues. It showed a good safety profile with easy deployment and removal. It promises a new standard in stenting.

Comparison Between Holmium:YAG Laser with MOSES Technology vs Thulium Fiber Laser Lithotripsy in Retrograde Intrarenal Surgery for Kidney Stones in Adults: A Propensity Score-matched Analysis From the FLEXible Ureteroscopy Outcomes Registry

PURPOSE

We evaluated stone-free rate and complications after flexible ureteroscopy for renal stones, comparing thulium fiber laser and holmium:YAG laser with MOSES technology.

MATERIALS AND METHODS

Data from adults who underwent flexible ureteroscopy in 20 centers worldwide were retrospectively reviewed (January 2018-August 2021). Patients with ureteral stones, concomitant bilateral procedures, and combined procedures were excluded. One-to-one propensity score matching for age, gender, and stone characteristics was performed. Stone-free rate was defined as absence of fragments >2 mm on imaging within 3 months after surgery. Multivariable logistic regression analysis was performed to evaluate independent predictors of being stone-free.

RESULTS

Of 2,075 included patients, holmium:YAG laser with MOSES technology was used in 508 patients and thulium fiber laser in 1,567 patients. After matching, 284 patients from each group with comparable baseline characteristics were included. Pure dusting was applied in 6.0% of cases in holmium:YAG laser with MOSES technology compared with 26% in thulium fiber laser. There was a higher rate of basket extraction in holmium:YAG laser with MOSES technology (89% vs 43%, P < .001). Total operation time and lasing time were similar. Nine patients had sepsis in thulium fiber laser vs none in holmium:YAG laser with MOSES technology (P = .007). Higher stone-free rate was achieved in thulium fiber laser (85% vs 56%, P < .001). At multivariable analysis, the use of thulium fiber laser and ureteral access sheath ≥8F had significantly higher odds of being stone-free. Lasing time, multiple stones, stone diameter, and use of disposable scopes showed significantly lower odds of being stone-free.

CONCLUSIONS

This real-world study favors the use of thulium fiber laser over holmium:YAG laser with MOSES technology in flexible ureteroscopy for renal stones by way of its higher single-stage stone-free rate.

A Feasibility Study on Clinical Utility, Efficacy and Limitations of 2 Types of Flexible and Navigable Suction Ureteral Access Sheaths in Retrograde Intrarenal Surgery for Renal Stones

OBJECTIVE

To evaluate stone-free rate, device maneuverability, and complications after retrograde intrarenal surgery (RIRS) using 2 different sizes of flexible and navigable suction ureteral access sheaths (FANS).

METHODS

A retrospective analysis was performed for patients who underwent RIRS for renal stones of any size, number, and location between November 2021 and October 2022. Group 1 had FANS of 12 French. Group 2 had FANS of 10 French. Both sheaths have a Y-shaped suction channel. Tip of 10 French FANS has 20% more flexibility. Lithotripsy was achieved using either thulium fiber or high-power holmium lasers. A 5-point Likert scale was used to assess the performance of each sheath.

RESULTS

There were 16 patients in Group 1 and 15 patients in Group 2. Baseline demographics and stone parameters were similar. Four patients in Group 2 had the same session bilateral RIRS. Sheath insertion was successful in all renal units but one. Ten French FANS had a higher percentage of excellent scores for ease of use, manipulation, and visibility. Neither of the sheaths had an average or difficult rating for all evaluation scales. A fornix rupture requiring prolonged stenting occurred in group 2. All patients were discharged within 24 hours of surgery. One patient in each group visited the emergency department (analgesic treatment). There were no infectious complications. At 3 months, a computed tomography scan showed that the absence of residual fragments >2 mm was significantly higher in Group 2 (94.7% vs 68.8%, P = 0.01).

CONCLUSION

The 10 Fr FANS showed a higher stone-free rate. There was no infectious complication using both sheaths.

Improving Outcomes of Same-sitting Bilateral Flexible Ureteroscopy for Renal Stones in Real-world Practice-Lessons Learnt from Global Multicenter Experience of 1250 Patients

Background

Bilateral kidney stones are commonly treated in staged procedures.

Objective

To evaluate outcomes after same-sitting bilateral retrograde intrarenal surgery (SSB-RIRS) for renal stones.

Design setting and participants

Data from adults who underwent bilateral RIRS in 21 centers were retrospectively reviewed (from January 2015 to June 2022). The inclusion criteria were unilateral/bilateral symptomatic bilateral stone(s) of any size/location in both kidneys and bilateral stones on follow-up with symptom/stone progression. Stone-free rate (SFR) was defined as absence of any fragment >3 mm at 3 mo.

Outcome measurements and statistical analysis

Continuous variables are presented as medians and 25-75th percentiles. A multivariable logistic regression analysis was performed to evaluate independent predictors of sepsis and bilateral SFR.

Results and limitations

A total of 1250 patients were included. The median age was 48.0 (36-61) yr. Of the patients, 58.2% were prestented. The median stone diameter was 10 mm on both sides. Multiple stones were present in 45.3% and 47.9% of the left and right kidneys, respectively. Surgery was stopped in 6.8% of cases. The median surgical time was 75.0 (55-90) min. Complications were transient fever (10.7%), fever/infection needing prolonged stay (5.5%), sepsis (2%), and blood transfusion (1.3%). Bilateral and unilateral SFRs were 73.0% and 17.4%, respectively. Female (odds ratio [OR] 2.97, 95% confidence interval [CI] 1.18-7.49, p = 0.02), no antibiotic prophylaxis (OR 5.99, 95% CI 2.28-15.73, p < 0.001), kidney anomalies (OR 5.91, 95% CI 1.96-17.94, p < 0.001), surgical time ≥100 min (OR 2.86, 95% CI 1.12-7.31, p = 0.03) were factors associated with sepsis. Female (OR 1.88, 95% CI 1.35-2.62, p < 0.001), bilateral prestenting (OR 2.16, 95% CI 1.16-7.66, p = 0.04), and the use of high-power holmium:YAG laser (OR 1.63, 95% CI 1.14-2.34, p < 0.01) and thulium fiber laser (OR 2.50, 95% CI 1.32-4.74, p < 0.01) were predictors of bilateral SFR. Limitations were retrospective study and no cost analysis.

Conclusions

SSB-RIRS is an effective treatment with an acceptable complication rate in selected patients with kidney stones.

Patient summary

In this large multicenter study, we looked at outcomes after same-sitting bilateral retrograde intrarenal surgery (SSB-RIRS) for renal stones in a large cohort. We found that SSB-RIRS was associated with acceptable morbidity and good stone clearance after a single session.

Technique, Feasibility, Utility, Limitations, and Future Perspectives of a New Technique of Applying Direct In-Scope Suction to Improve Outcomes of Retrograde Intrarenal Surgery for Stones

Retrograde intrarenal surgery (RIRS) is accepted as a primary modality for the management of renal stones up to 2 cm. The limitations of RIRS in larger volume stones include limited visualization due to the snow-globe effect and persistence of fragments that cannot be removed. We describe a new, simple, cost-effective modification that can be attached to any flexible ureteroscope which allows simultaneous/alternating suction and aspiration during/after laser lithotripsy using the scope as a conduit to remove the fragments or dust from the pelvicalyceal system called direct in-scope suction (DISS) technique. Between September 2020 and September 2021, 30 patients with kidney stones underwent RIRS with the DISS technique. They were compared with 28 patients who underwent RIRS with a 11Fr/13Fr suction ureteral access sheaths (SUASs) in the same period. RIRS and laser lithotripsy were carried out traditionally with a Holmium laser for the SUAS group or a thulium fiber laser for the DISS group. There was no difference in age, gender, and history of renal lithiasis between the two groups. Ten (40%) patients had multiple stones in the DISS groups, whilst there were no patients with multiple stones in the SUAS group. Median stone size was significantly higher in the DISS group [22.0 (18.0−28.8) vs. 13.0 (11.8−15.0) millimeters, p < 0.001]. Median surgical time was significantly longer in the DISS group [80.0 (60.0−100) minutes] as compared to the SUAS group [47.5 (41.5−60.3) minutes, p < 0.001]. Hospital stay was significantly shorter in the DISS group [1.00 (0.667−1.00) vs. 1.00 (1.00−2.00) days, p = 0.02]. Postoperative complications were minor, and there was no significant difference between the two groups. The incidence of residual fragments did not significantly differ between the two groups [10 (33.3%) in the DISS group vs. 10 (35.7%) in the SUAS group, p = 0.99] but 10 (33.3%) patients required a further RIRS for residual fragments in the DISS group, whilst only one (3.6%) patient in the SUAS group required a subsequent shock wave lithotripsy treatment. Our audit study highlighted that RIRS with DISS technique was feasible with an acceptable rate of retreatment as compared to RIRS with SUAS.

Radiomics in Urolithiasis: Systematic Review of Current Applications, Limitations, and Future Directions

Radiomics is increasingly applied to the diagnosis, management, and outcome prediction of various urological conditions. Urolithiasis is a common benign condition with a high incidence and recurrence rate. The purpose of this scoping review is to evaluate the current evidence of the application of radiomics in urolithiasis, especially its utility in diagnostics and therapeutics. An electronic literature search on radiomics in the setting of urolithiasis was conducted on PubMed, EMBASE, and Scopus from inception to 21 March 2022. A total of 7 studies were included. Radiomics has been successfully applied in the field of urolithiasis to differentiate phleboliths from calculi and classify stone types and composition pre-operatively. More importantly, it has also been utilized to predict outcomes and complications after endourological procedures. Although radiomics in urolithiasis is still in its infancy, it has the potential for large-scale implementation. Its greatest potential lies in the correlation with conventional established diagnostic and therapeutic factors.

Renal autotransplantation following long segment iatrogenic ureteric injury

The authors describe a case of iatrogenic right ureteric injury post duodenectomy and right hemi-colectomy. Renal autotransplantation was chosen as the treatment for the upper ureteric injury. This was successfully performed and the renal function of the transplanted kidney was subsequently preserved. The advantages and disadvantages of this approach are discussed.

Correlation of intravesical prostatic protrusion with bladder outlet obstruction

OBJECTIVES

To determine the effect of intravesical protrusion of the prostate (IPP, graded I to III) on lower urinary tract function, by correlating it with the results of a pressure-flow study.

PATIENTS AND METHODS

In a prospective study men (aged> 50 years) with lower urinary tract symptoms were initially evaluated as recommended by the International Consultation on Benign Prostatic Hyperplasia, together with the IPP and prostate volume, as measured by transabdominal ultrasonography. These variables were then correlated with the results from a pressure-flow study.

RESULTS

The IPP was a statistically significant predictor (P < 0.001) of bladder outlet obstruction (BOO) compared with other variables in the initial evaluation. In all, 125 patients had significant BOO, defined as a BOO index of> 40. Of these men, 94 had grade III and 30 had grade I-II IPP. Seventy-five patients had a BOO index of < 40; 69 had grade I-II and six grade III IPP. In patients with BOO confirmed on the pressure-flow study, grade III IPP was associated with a higher BOO index than was grade I-II (P < 0.001).

CONCLUSION

The IPP assessed by transabdominal ultrasonography is a better and more reliable predictor of BOO than the other variables assessed.

Hepatolithiasis--a case series

INTRODUCTION

Hepatolithiasis is an uncommon entity in Singapore. We reviewed the cases presented to our institution (a 1200-bedded restructured hospital) over a 5-year period.

MATERIAL AND METHODS

Twelve cases of hepatolithiasis were treated between December 1995 and July 2000 representing 0.77% of gallstone disease operated on in the same period. The clinical presentation, investigations, treatment and subsequent progress are presented.

RESULTS

The patients' ages ranged from 28 to 82 years. There was a male to female ratio of 5:7. All patients had upper abdominal pain at presentation; 10 patients had clinical evidence of cholangitis. Ultrasound was the commonest first line investigation but additional investigations, such as computed tomographic (CT) scan and various forms of cholangiography, were frequently necessary for complete delineation of the biliary disease. The intrahepatic stones were located predominantly in the left lobe of the liver. Parenchymal atrophy was seen in 83% of patients. Two patients underwent a biliary bypass operation only, 5 had a hepatic resection only, and 5 had combined procedures. Follow-up ranged from 4 to 50 months. Postoperative recovery was generally unremarkable. Complications included subphrenic abscess (1 patient), recurrent stricture (1 patient) and recurrent stones (1 patient). One patient had an elevated serum CA 19-9 preoperatively; a small villous adenoma was noted at the biliary stricture in the resected left lateral segment of the liver. There was no operative mortality.

CONCLUSION

Hepatolithiasis is uncommon in Singapore. Complete diagnosis requires a combination of imaging modalities. Surgery remains the mainstay of definitive treatment. With adequate treatment, good outcome is possible.