Tissue Sensor for Semirigid Thulium Fiber Laser Ureterolithotripsy

Tissue Sensor (TS) is a technology designed to automatically deactivate laser emission when contact between the laser fiber and tissue is detected. It is hypothesized that the use of TS during contact laser ureterolithotripsy may reduce unintended laser exposure of the ureteral mucosa, thereby decreasing the risk of immediate thermal injury to the ureteral wall and subsequent scar-related narrowing. To reduce the influence of baseline risk factors for stricture, the study will enroll a homogeneous population of patients without urinary tract anomalies, previous surgery on the study ureter, or impacted stones. The procedure will be performed according to a standardized protocol using a semirigid ureteroscope, a thulium fiber laser, and predefined technical restrictions. The study is limited to patients with stones in the mid or distal ureter. This approach is intended to minimize the likelihood of stone retropulsion into the kidney, standardize the surgical technique, reduce the need for conversion to flexible ureteroscopy, and maximize comparability between the study groups.