A Retrospective Observational Study for Prediction of Stone Free Status after Single-session of Retrograde Intrarenal Surgery for Renal Stones

Abstract

Introduction: Retrograde Intrarenal Surgery (RIRS) is a preferred minimal invasive treatment modality for renal stones with advantages of being effective and having lower morbidity rates. Aim: To predict the Stone Free Rate (SFR) after RIRS with lower pole and non-lower pole stones. Materials and Methods: The records of 85 consecutive patients who underwent unilateral RIRS from September 2016 to July 2019 were retrospectively analysed. The studied parameters included patient demographics, stone characteristics (size, volume, and attenuation, Lower Pole Infundibulopelvic Angle (LP IPA) and operative time, presence of preoperative Double-J Stent (DJS) and Stone Free Status (SFS). Standard statistical tests were applied with level of significance as p45° were stone free. Patients with non-lower pole stones has SFR 2.8 times compared to LP stones (p<0.001). On linear regression analysis, only LP IPA and LP stone location predicts SFS after RIRS. Conclusion: Retrograde Intrarenal Surgery (RIRS) is effective procedure for renal stones. Stone size, stone volume, Lower Pole (LP) stone location and LP IPA effectively predict SFR. However, LP IPA and LP stone location are the most significant predictor of SFS, after single session RIRS for solitary renal stone.

Keywords

• infundibulopelvic angle
• lower pole
• stone location