Supine or prone percutaneous nephrolithotomy: do anatomical changes make it worse?

Area of Science:

• Urology
• Medical Imaging
• Surgical Anatomy

Background:

• Percutaneous nephrolithotomy (PCNL) is a key procedure for kidney stones.
• Patient positioning (supine, prone) impacts surgical access and safety.
• Understanding anatomical variations is crucial for minimizing complications.

Purpose of the Study:

• To compare anatomical properties across supine, prone, and prone-flex positions for PCNL.
• To assess the risk of visceral organ injury associated with each position.

Main Methods:

• 30 patients with large renal stones (>2 cm) underwent CT scans in three positions.
• Key measurements included access tract length, subcutaneous tissue, nearest organ distance, access angle, and access field.
• Statistical analysis used paired t-tests and Wilcoxon signed tests.

Main Results:

• Supine position showed longer overall tract and subcutaneous tissue lengths.
• Subcutaneous tissue thickness was the primary determinant of tract length.
• Access field was significantly shorter in the supine position compared to prone positions.
• Nearest organ distance to the access tract was similar across positions.

Conclusions:

• Supine positioning for PCNL does not elevate the risk of visceral organ injury.
• Supine PCNL may offer advantages but poses challenges with longer access tracts and a more limited access field.
• Surgeons must consider these anatomical and technical differences for optimal outcomes.