RETROGRADE INTRA RENAL SURGERY FOR RENAL STONES

Introduction and Objectives: Urolithiasis affects 5–15% of the population during their lives. Stone recurrence rate can be as high as 50% during life. The improvement of mininvasive techniques led to an important decrease of the open surgery, nowadays unnecessary in most cases. Extracorporeal shock wave lithotripsy (ESWL) was introduced in the 1980s as a revolutionary technique to fragment renal and ureteral calculi. Due to ESWL limits, other mininvasive techniques were performed to treat renal calculi such as percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). Today the boundary between the indications of this three procedures is not well defined, especially considering patients with multiple stone relapses who undergo many sessions of treatment during their lives. The purposes of this study are to evaluate effectiveness and safety of RIRS; to assess its potential use as first line treatment of renal medium-sized stones (10–20mm); to set RIRS in the management of people prone to multi stone recurrences. Material and Methods: This prospective study considered 35 renal stone patients who underwent RIRS in our department. In this study we analysed location, number and diameter of renal calculi using the conventional imaging methods and their composition. We evaluated the different surgical instrumentation necessary to obtain successful result, type and length of the ureteral stenting, number of hospitalization days, intra and post-operative complications of the treatment. RIRS results were evaluated after three months with abdominal ultrasound and plain abdominal x-ray. Results: Stone free rate was achieved in 63% and 80% after single procedure and retreatment respectively. Single calculus were treated more successfully (83%) than multiple stones (41%) (p = 0.002). RIRS results and stone dimension are related with statistic significance (p = 0.004): retrograde intrarenal surgery is able to dissolve with higher success renal calculi smaller than 20 mm. 7% of treatments had post-operative complications. We did not find statistically significant differences in efficacy and safety between patients with renal stone relapse and patients with their first episode of calculi disease. Conclusions: RIRS is an effective and safe procedure to treat renal calculi. It may be considered as the first-line therapy to treat renal stones smaller than 20mm. It may be the first option to manage patients with multiple stone relapses. They are suggested to take an intensive follow up in order to diagnose and treat renal stones when they are still smaller than 20 mm.