Is the Success and Safety of Retrograde Intrarenal Surgery Related to the Opacity Status of Kidney Stones? A Critical Evaluation

Abstract

Aim: This present study aimed to investigate the possible effect of the opacity status of kidney stones on the success and complication rates observed during and after retrograde intrarenal surgery (RIRS). Material and Method: This study analyzed the data of 642 kidney stone cases who underwent flexible ureteroscopy between February 2014 and April 2022. In all patients, non-contrast computed tomography and kidney-ureter-bladder (KUB) radiography were performed preoperatively to evaluate the anatomy of the collecting system and the structure of the kidney stone. The patients were divided into two groups as opaque and non-opaque according to the opacity evaluation based on the preoperative KUB image. While 359 patients had radiopaque stones, 283 patients had non-opaque stones. Both groups were compared in terms of certain preoperative data, postoperative outcomes, and complications. Results: Cases with non-opaque stones were ahead of the other group in terms of the American Society of Anaesthesiologists (ASA) score, diagnosed diabetes mellitus, Charlson Comorbidity Index, and body mass index. In the third postoperative month, there was no statistically significant difference between the two groups in terms of stone-free status (72.1% vs 75.3%, p=0.212). Postoperative infective complications and hospital stays were comparable across the two groups, despite the non-opaque stone group being substantially older and farther along in terms of comorbidities. Conclusion: This study’s results showed that RIRS could be applied with successful outcomes regardless of the opacity status of renal stones.

Keywords

• opaque
• non-opaque
• RIRS
• kidney stones

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