Predicting calyceal access for percutaneous nephrolithotomy with computed tomography multiplanar reconstruction.

Area of Science:

• Urology
• Medical Imaging
• Nephrology

Background:

• Percutaneous nephrolithotomy (PCNL) is a key procedure for kidney stone removal.
• Predictive parameters for successful calyceal access in PCNL using computed tomography (CT) have not been well-established.
• Improved access planning can enhance PCNL outcomes.

Purpose of the Study:

• To identify objective parameters from preoperative multiplanar reconstructed CT scans that predict renal calyceal access during PCNL.
• To evaluate the utility of CT-derived measurements in guiding PCNL access strategies.

Main Methods:

• Analysis of 284 PCNL procedures performed between January 2009 and April 2011.
• Inclusion of 11 patients with complete staghorn calculi (13 renal units).
• Extraction of five parameters from preoperative CT scans and comparison with surgical outcomes.

Main Results:

• Univariate analysis indicated that the target calyx for access had smaller length, larger angles, and larger infundibula.
• Multivariate analysis identified the angle between the entrance calyx and the target calyx as the sole independent predictor of successful access.
• The angle between calyces was significantly associated with access success (OR 1.15, 95% CI 1.053-1.256, p=0.002).

Conclusions:

• The angle between calyces, as measured by multiplanar CT reconstruction, is a significant predictor of calyceal access during PCNL.
• This CT-derived parameter can aid in preoperative planning for percutaneous nephrolithotomy.
• Further validation of this parameter may optimize surgical approaches for kidney stone management.