Residual fragments after percutaneous nephrolithotomy

Area of Science:

• Urology
• Nephrology
• Medical Imaging

Background:

• Clinically insignificant residual fragments (CIRFs) are stone fragments ≤4 mm remaining after urinary stone treatment.
• The significance of CIRFs is debated due to potential for recurrent stone growth, pain, and infection.

Purpose of the Study:

• To evaluate the clinical implications of CIRFs after urinary stone interventions.
• To discuss optimal assessment and management strategies for CIRFs.

Main Methods:

• Review of current literature on CIRFs after extracorporeal shock wave lithotripsy (ESWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL).
• Discussion of imaging modalities, particularly CT, for CIRF assessment.
• Analysis of treatment options including medical therapy and surgical intervention.

Main Results:

• CIRFs can lead to significant stone-related events, including recurrent stone formation and infections.
• CT is the preferred imaging modality for assessing CIRFs, with optimal timing debated but potentially one month post-procedure.
• Selective medical therapy may reduce stone formation rates.

Conclusions:

• CIRFs pose a risk of future complications and should not be disregarded.
• Retrograde intrarenal surgery (RIRS) is presented as the most effective minimally invasive approach for managing residual fragments.