The residual renal stone.

Area of Science:

• Nephrology
• Radiology
• Urology

Background:

• Preoperative radiography is crucial for diagnosing renal stones.
• Observer error in interpreting radiographs can lead to missed diagnoses.
• Understanding the long-term behavior of renal calculi is essential for patient management.

Purpose of the Study:

• To evaluate observer error in preoperative radiography for renal stones.
• To assess the long-term outcomes of staghorn calculi removal, including stone recurrence and residual stone behavior.

Main Methods:

• Analysis of observer error in preoperative radiographs for stones < 2 mm.
• Radiographic follow-up of 100 patients after staghorn calculi removal (120 calculi).
• Observation period of up to 10 years post-surgery.

Main Results:

• Radiography frequently misses renal stones smaller than 2 mm.
• New calculi formation observed in kidneys previously cleared of stones.
• Residual stones exhibited varied behavior: some grew, some passed spontaneously, and others remained unchanged.

Conclusions:

• Preoperative radiography has limitations in detecting small renal stones.
• Kidneys cleared of staghorn calculi are susceptible to new stone formation.
• The natural history of residual renal stones is variable, necessitating long-term monitoring.