Objective: This study aimed to evaluate the feasibility of the fluoroscopy-free single-use flexible ureteroscopy procedure in the treatment of kidney stones with abnormal renal anatomy compared to normal renal anatomy.

Methods: Forty patients with abnormal (Group A) and 80 patients with normal (Group B) renal anatomy who had 10-20 mm renal stones were included. They were treated with LithoVue single-use flexible ureteroscopy (Boston Scientific, Marlborough, MA, USA) after ureteric dilatation by two different size semi-rigid ureteroscopes. This technique was chosen as the aim was to exclude any ureteric pathology (e.g., stone or stricture), confirm the placement of a safe guidewire, avoid balloon dilatation of the ureter, and achieve safe insertion of a 12 Fr, 35/45 cm ureteric access sheath with optical and tactile sign and without fluoroscopy image for guidance.

Results: The mean ages were 43 years and 45 years in Group A and Group B, respectively. The mean stone burden was 14.62 (standard deviation: 5.35) mm³ and 14.79 (standard deviation: 4.58) mm³ in Group A and Group B, respectively. There is no significant difference between both groups according to the mean operative time, hospital stay, or stone-free rate. The stone-free rate was about 93% in both groups when the stone size was between 10 mm and 15 mm, and less than 54% when the stone size was more than 15 mm to 20 mm. In the majority of cases (80.0% in Group A and 92.5% in Group B), we completed the procedure without fluoroscopy. The perioperative complication rates were comparable in the two groups.

Conclusion: Fluoroscopy-free single-use flexible ureteroscopy, when performed by expert urologists, is a feasible treatment for pre-stented patients with kidney calculi of ≤15 mm with abnormal renal anatomy.