Clinical Scorecard: Evaluating the Role of Flexible and Navigable Suction Access Sheath (FANS) in Patients Undergoing Concurrent Flexible Ureteroscopy for Bilateral Kidney Stones: A Global Prospective Multicenter Study by EAU Endourology

At a Glance

Key Highlights

• Bilateral KSD doubles surgical intervention risk and impacts quality of life; single-session bilateral procedures offer cost and resource benefits.
• FANS demonstrated high ease of use, effective suction, and maneuverability within the pelvicalyceal system, contributing to improved surgical vision and outcomes.
• Overall bilateral 100% stone-free rate (zero residual fragments) achieved in 42.6% of patients with low complication rates and minimal need for sheath changes.

Guideline-Based Recommendations

Diagnosis

• Use non-contrast CT scans (NCCT) pre- and post-operatively to assess stone volume and residual fragments.
• Classify residual fragments post-procedure into Grades A-D based on size to guide management.

Management

• Consider same-sitting bilateral RIRS with FANS for suitable adult patients with bilateral renal stones and normal anatomy.
• Treat positive urine cultures preoperatively according to antibiogram.
• Pre-stenting is not mandatory when using FANS.
• Use Holmium or Thulium fiber laser for lithotripsy during FURS.

Monitoring & Follow-up

• Perform 30-day post-operative NCCT to assess stone-free status and residual fragments.
• Inspect ureteral mucosa intraoperatively and document injuries using Traxer-Thomas classification.
• Monitor for perioperative complications including bleeding, ureteric injury, infections, and pain scores.

Risks

• Potential for residual fragments requiring re-intervention, especially if fragments >4 mm (Grade D).
• Low but present risk of ureteral injury and infective complications.
• Need for careful patient selection to avoid anatomical anomalies and ensure follow-up compliance.

Patient & Prescribing Data

115 adult patients with bilateral kidney stones undergoing SSB-RIRS with FANS across 14 centers

FANS was successfully deployed bilaterally in all cases with 98.2% suction success; 42.6% achieved complete bilateral stone-free status at 30 days; majority had bilateral ureteral stents placed postoperatively; low rate (1.7%) of sheath change required.

Clinical Best Practices

• Ensure patient selection excludes those with anomalous pelvicalyceal anatomy, ureteral stones, age under 18, or inability to follow up with NCCT.
• Use a standardized protocol for preoperative assessment including stone volume calculation and urine culture treatment.
• Employ FANS models with proven maneuverability and suction efficacy, rating ease of use on a Likert scale.
• Perform thorough intraoperative inspection and retrograde pyelogram to document ureteral integrity.
• Follow EAU guidelines for residual fragment classification to guide postoperative management and surveillance.

References

• EAU Guidelines on Urolithiasis
• Castellani et al. on bilateral PCNL and RIRS safety
• Randomized controlled trial on FANS efficacy
• Traxer-Thomas classification for ureteral injury