Simultaneous bilateral retrograde intrarenal surgery with thulium fiber laser.

Introduction. Urolithiasis is a common disease and up to 15% of patients have multiple kidney stones. Retrograde intrarenal surgery (RIRS) can be used in the surgical treatment of kidney stones because this method is highly effective. Patients with multiple kidney stones often necessitate several surgeries. In this study we our own experience of bilateral RIRS to analyze its effectiveness and safety. Materials and methods. From January 2021 to February 2022 the simultaneous bilateral RIRS were performed to 11 patients (7 man and 4 woman). The maximal size of stone was 21 mm (the average size of the right kidney was 15,0 mm ± 6,0 mm and the left kidney – 11,7 mm ± 4,3 mm). Average stone density was more than 1000 HU. The mean age of the patients was 57±13 years. Bilateral retrograde intrarenal surgery was performed simultaneously by two surgeons using flexible ureteroscopes using a SuperPulsed thulium fiber laser. The following parameters were assessed: surgical intervention time; stone free rate (SFR); degree of ureteral injury according to the post-ureteroscopic lesion scale (PULS); the need for drainage of the ureter in the postoperative period, assessment of the creatinine level, glomerular filtration rate (GFR) and C-reactive protein in the postoperative period; postoperative complications according to the Clavien-Dindo classification. Results and their discussion. The average duration of the surgery was 56±11 minutes. The SFR level was 90,9 %. At the final inspection of the ureters: on the right side injury Grade 0 according to the PULS scale was recorded in 10 patients, Grade 1 – in 2 patients; on the left side Grade 0 – in 9 patients, Grade 1 – in 2 patients. The surgery was completed with the installation of ureteral catheters in 10 and 9 cases on the right and left sides, respectively. Three surgical interventions ended with the installation of ureteral stents on one side or another. The level of creatinine and C-reactive protein in the postoperative period increased on average by 10.2±5.7 μmol/l and 1.8±0.6 mg/l, respectively. The GFR decreased by 7.2 ± 2.6 ml/min. A complication was registered in 1 patient – increased body temperature on the 1st day, stopped by antibiotic therapy (Clavien-Dindo II). Conclusions. Simultaneous bilateral RIRS using single-use flexible ureteroscopes and a SuperPulsed thulium fiber laser is a safe and effective procedure for patients with bilateral nephrolithiasis.