Kidney volume loss following percutaneous nephrolithotomy utilizing 3D planimetry

Area of Science:

• Urology
• Nephrology
• Medical Imaging

Background:

• Parenchymal damage and impaired renal function are concerns after percutaneous nephrolithotomy (PCNL).
• Understanding post-operative renal volume changes is crucial for assessing PCNL outcomes.

Purpose of the Study:

• To evaluate post-operative changes in total kidney volume (TKV) after PCNL.
• To identify factors associated with renal volume loss following PCNL.

Main Methods:

• Retrospective analysis of CT images from 25 patients before and after PCNL.
• Utilized 3D planimetry software for segmentation and measurement of TKV, kidney surface area, and stone characteristics.
• Statistical analysis included Wilcoxon signed-rank test, univariate, and multivariable analyses.

Main Results:

• A statistically significant average decline of 21% in TKV was observed post-PCNL (225.25 cm³ to 178.09 cm³).
• No significant difference in pre- and post-operative serum creatinine levels was found.
• Higher TKV loss correlated with larger kidney stone surface area and a history of previous PCNL. Younger age was protective against TKV loss.

Conclusions:

• PCNL leads to a consistent decrease in TKV.
• Factors such as larger stone burden and prior PCNL procedures exacerbate TKV loss.
• Despite volume reduction, renal function (serum creatinine) appears preserved in the short term.