Clinical Scorecard: Comparative Analysis of Efficacy and Safety Between Flexible and Navigable Suction Ureteral Access Sheath (FANS) and Traditional Access Sheath in Bilateral Same Session Flexible Ureteroscopy: A Prospective Randomized Study

At a Glance

Key Highlights

• Bilateral same-session flexible ureteroscopy reduces operative time, anesthesia exposure, and hospital stay compared to staged procedures.
• Traditional ureteral access sheaths have limitations including retention of stone fragments, prolonging procedure and increasing adverse events.
• FANS device offers enhanced maneuverability with a 270° bending distal segment and suction capability, improving stone-free rates and postoperative outcomes.

Guideline-Based Recommendations

Diagnosis

• Use non-contrast CT (NCCT) to evaluate stone size, location, number, hydronephrosis, and density prior to surgery.
• Perform urine culture preoperatively and treat any infection according to sensitivity.

Management

• Consider bilateral same-session flexible ureteroscopy for eligible patients to reduce overall treatment time and hospital stay.
• Use TUAS or FANS during flexible ureteroscopy based on surgeon preference and patient anatomy.
• Employ Holmium:YAG laser lithotripsy with appropriate energy settings for stone fragmentation.
• Use retrieval baskets as needed for stone extraction.

Monitoring & Follow-up

• Assess stone-free status 1 month postoperatively by NCCT, categorizing residual fragments as Grade A (no fragments), B (≤2 mm), or C (2.1–4 mm).
• Monitor for intraoperative adverse events, especially ureteral injury risks during bilateral procedures.

Risks

• Potential for ureteral injury during bilateral same-session procedures leading to long-term morbidity.
• Increased adverse events associated with retained stone fragments when using traditional access sheaths.

Patient & Prescribing Data

Adults with bilateral renal or upper ureteric stones less than 20 mm, excluding pediatric patients with untreated coagulopathies or stones in calyceal diverticula.

Randomized allocation to TUAS or FANS groups showed FANS may improve stone-free rates and reduce adverse events due to enhanced suction and maneuverability.

Clinical Best Practices

• Preoperative optimization including urine culture and antibiotic treatment if indicated.
• Use of safety guidewire and semi-rigid ureteroscopy for passive ureteric dilation prior to sheath insertion.
• Selection of sheath size based on ureteral dilation and stone location.
• Perform flexible ureteroscopy under general anesthesia with fluoroscopic guidance for sheath placement.
• Prioritize treatment of symptomatic side first or according to stone burden and access difficulty.
• Postoperative imaging follow-up at 1 month to evaluate stone clearance.

References

• Prevalence of bilateral stone disease
• Surgical treatment options for bilateral stone disease
• Advantages of flexible ureteroscopy over PCNL and shock wave therapy
• Benefits of simultaneous bilateral flexible ureteroscopy
• Concerns about intraoperative adverse events in bilateral procedures
• Limitations of traditional ureteral access sheaths
• Development and benefits of FANS device
• Ethical principles and study conduct