Non-ablative transurethral laser treatment for collagen remodeling with functional recovery in an in vivo model of stress urinary incontinence

Stress urinary incontinence (SUI) is a common condition characterized by involuntary urine leakage under increased intra-abdominal pressure, such as coughing and physical exertion. The current treatments, including pelvic floor muscle training and surgical interventions such as mid-urethral sling procedures, remain limited by variable efficacy, invasiveness, and potential complications. This study aimed to develop and evaluate a novel, non-ablative transurethral 980 nm laser treatment as a minimally invasive, non-implantable alternative using a vaginal distension (VD)-induced SUI guinea pig model. Twelve female guinea pigs were randomly assigned to control, SUI, and laser treatment (SUI+LASER) groups. The VD model was induced by inserting a 10 Fr catheter into the vagina and expanding it for 1 h. After the VD, the SUI+LASER group received 980 nm irradiation (10 W, 5 s) applied transurethrally. Leak point pressure increased by 65% in the SUI+LASER group from day 0 to day 14. Histological analysis revealed significantly enhanced collagen deposition and muscle thickness in the SUI+LASER group, suggesting improved functional muscle recovery. These findings indicate that transurethral 980 nm laser treatment could effectively promote urethral tissue regeneration in the SUI model. Further studies will validate the long-term safety and efficacy of the proposed treatment for clinical applications.