Is There a Role for Prone Computed Tomography Before Percutaneous Nephrolithotomy?

Area of Science:

• Urology
• Medical Imaging
• Surgical Planning

Background:

• Percutaneous nephrolithotomy (PCNL) is commonly performed in the prone position.
• Preoperative CT scans are typically acquired in the supine position.
• This discrepancy may impact surgical planning and patient safety.

Purpose of the Study:

• To evaluate the utility of prone CT scans in preoperative planning for prone PCNL.
• To identify patient groups at higher risk for organ injury and tract length complications.
• To assess the impact of patient positioning on percutaneous tract length estimations.

Main Methods:

• Two-dimensional axial prone and supine percutaneous tract measurements were performed.
• Tract lengths were minimized from target calix to posterior-lateral skin.
• Organ interception rates and tract length differences were recorded and analyzed.

Main Results:

• Female gender and low BMI predicted organ interception on the left.
• Tract lengths could change significantly when repositioning from supine to prone.
• Shorter supine tracts tended to lengthen, and longer supine tracts tended to shorten in prone position.

Conclusions:

• Prone CT may benefit planning for PCNL cases with anticipated exceptionally long tract lengths (>15 cm).
• Prone scans identified more potential organ interceptions, particularly in women with low BMI in the left upper pole.
• Urologists should consider alternate targets or ultrasound guidance if prone CT reveals organ interception.