Predictive Factors for Multiple Sessions of Retrograde Intrarenal Surgery to Achieve Stone-Free Status

Area of Science:

• Urology
• Nephrology
• Surgical Innovation

Background:

• Nephrolithiasis, or kidney stones, affects a significant portion of the population.
• Retrograde intrarenal surgery (RIRS) is a minimally invasive treatment option for kidney stones.
• Achieving stone-free status after RIRS is a key outcome measure.

Purpose of the Study:

• To identify predictive factors for requiring multiple RIRS sessions to achieve stone-free status.
• To differentiate patient and stone characteristics associated with single versus multiple RIRS interventions.
• To improve patient selection and treatment planning for RIRS.

Main Methods:

• A descriptive study involving 487 patients who underwent RIRS for renal stones.
• Patients were categorized into two groups: single RIRS session (Group I) and multiple RIRS sessions (Group II).
• Logistic regression analysis was used to identify predictive factors for multiple RIRS sessions.

Main Results:

• Stone location in the lower calyx, presence of hydronephrosis, and higher stone volume were significant predictors for requiring multiple RIRS sessions (p = 0.042, p = 0.018, p = 0.040).
• Patient demographics (gender, age) and other stone characteristics (density, number, size, laterality, operation time) were not predictive.
• These findings highlight specific indicators for potential multi-session treatment needs.

Conclusions:

• Patients with stones located in the lower calyx, hydronephrosis, and a substantial stone burden are less likely to achieve stone-free status in a single RIRS session.
• Conversely, patients without these indicators have a higher probability of successful treatment after one RIRS procedure.
• These factors can guide clinical decisions regarding the anticipated number of RIRS sessions required for effective nephrolithiasis management.