This comparative study aims to compare and assess the safety, efficacy, outcome, feasibility, intraoperative and postoperative complications of one-shot dilatation versus serial dilatation techniques for access during percutaneous nephrolithotomy for management of renal stone disease in adult patients.

Inclusion Criteria:

• Patients aged between 18 and 70 years.
• Patients with renal stones which their size in maximum diameter is more than 2cm and indicated for percutaneous nephrolithotomy.
• Patients clinically fit for surgery.
• Patients with normal anatomy of urinary tract.
• Patients able to understand the procedure and accept to sign the informed consent.

Exclusion Criteria:

• Patients aged below 18 or above 70 years.
• Patients with renal stones which their size in maximum diameter is less than 2cm or contraindicated for endoscopic management.
• Patients with urinary tract infection, abnormal coagulopathy state or clinically unfit for surgery.
• Patients with nephrostomy tube in situ.
• Patients with more than single access tract.
• Patients undergoing simultaneous bilateral stone procedures.
• Patients with urinary tract abnormalities or history of renal transplantation.
• Renal insufficiency with serum creatinine above 3.0mg/dL
• Patients unable to understand the procedure or refuse to sign the informed consent.