Comparison Between Two Methods for Renal Stone Treatment Mini Percutaneous Nephrolithotomy and Flexible Ureteroscopy With Suction Sheath

Mini-PCNL involves creating a small tract from the skin on the back directly into the kidney, through which a miniature nephroscope is passed to visualize and remove stones. Flexible Ureteroscopy is performed by passing a thin, flexible scope through the natural urinary passage (urethra and ureter) into the kidney. The specific FURS technique in this study utilizes a specialized scope with integrated suction, which is theorized to improve stone fragment clearance.

• mini-percutaneous nephrolithotomy (Procedure), also known as Mini-PCNL, mPCNL: Under general anesthesia, a 6 Fr ureteral catheter will be placed into the target ureter via cystoscopy, and bladder drainage will be achieved with a 16 Fr Foley catheter. The patient will then be repositioned to the prone position. Percutaneous renal access will be obtained by puncturing the selected calyx with an 18-gauge coaxial needle under fluoroscopic or ultrasound guidance. Tract dilation will be performed using fascial dilators up to 20 Fr then the mini-PCNL sheath (mini-Amplatz sheath) will be inserted and the mini nephroscope 12 to 15 Fr will be used. If multiple nephrostomy tracts are required for stone removal, the same approach will be repeated for each tract. Stone fragmentation will be carried out with a pneumatic lithotripter. At the end of the procedure, a 6 Fr double-J ureteral stent will be inserted for 4 weeks, and whether to place a nephrostomy tube will be determined at the discretion of the operating surgeon.
• Flexible Uerteroscopy with Tip-Bendable Suction Sheath (Procedure), also known as FANS, FURS with Suction Sheath: under general anesthesia with the patient in the lithotomy position. A 6 Fr ureteral catheter will first be placed into the ureter, followed by retrograde pyelography to assess the upper urinary tract. A guidewire will then be advanced into the renal pelvis. either a 12/14 Fr or 11/13 Fr tip-bendable S-UAS will be inserted. If insertion is not possible due to ureteral narrowing, a smaller 10/12 Fr UAS will be attempted. if failed, a double-J stent will be placed and the procedure terminated, with a second session scheduled 4 weeks later. fURS will be performed using digital flexible ureteroscopes either 8.5 Fr or 7.5 Fr according to UAS size; an 8.5-Fr scope for a 12/14 Fr UAS, and a 7.5-Fr scope for an 11/13-Fr or 10/12-Fr UAS. Stone fragmentation will be performed using a holmium laser (Ho: YAG) with a 272-μm fiber and an energy setting below 30 W. Irrigation will be maintained at 50-100 ml/min and suction pressure at 80-120 mmHg. at the end a 6 Fr JJ will be inserted for 4 weeks.

Primary outcomes

• stone free rate [one month postoperative]: The proportion of participants in each treatment arm who are completely free of any stone fragments in the treated kidney, following the initial procedure and without the need for any secondary surgical interventions. Status will be determined by a blinded central radiologist.

Secondary outcomes

• length of hospital stay [From date of surgery until date of hospital discharge for 14 days (measured in days).]: The total duration of inpatient hospitalization following the procedure, calculated from the day of surgery to the day of discharge
• operative time [Measured intraoperatively, from procedure start to end (in minutes).]: The total time from the initiation of the procedure to the final removal of all endoscopic equipment and placement/completion of any necessary stents

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Adult patients aging 18 years old or more.
* Patients with renal stones between 2-3 cm in size confirmed by CT scan.

Exclusion Criteria:

* Patients with previous ureteric injury.
* Patients with uncontrolled diabetes mellitus or hypertension.
* Patients with uncontrolled hepatic dysfunction.
* Patients with uremia or renal failure.
* Pregnant patients.
* patients with active urinary tract infection.
* Patients with bleeding tendency or uncontrolled coagulopathy.
* Patients with congenital anomalies as horse-shoe kidney and pelvi-ureteric junction obstruction.

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• Ahmed M Tawfeek, assistant proffessor, Study chair, Ain Shams University, Department Of Urology
• Ahmed Higazy, lecturer of urology, Study director, Ain Shams University, Department Of Urology
• Ashraf Satour, lecturer of urology, Study director, Ain Shams University, Department Of Urology