Vesicostomy in the Rat Model for Low-Pressure Urinary Drainage in Neurogenic Bladder Research

The rat is the primary animal model for preclinical research on spinal cord injury (SCI)-induced neurogenic lower urinary tract dysfunction (nLUTD). Owing to its anatomical and functional similarity to humans, rats closely recapitulate key pathological consequences of SCI. However, a crucial translational gap remains: whereas standard bladder management in humans typically relies on continuous or intermittent catheterization, comparable approaches are not feasible in rodents. The common practice of manual bladder expression generates exceptionally high intravesical pressures, which may introduce methodological bias by independently promoting pathological bladder remodeling after SCI. This protocol describes cutaneous vesicostomy in rats, together with postoperative wound management, to establish continuous low-pressure urinary drainage for preclinical SCI research. Cutaneous vesicostomy-the surgical creation of a stoma between the bladder dome and the lower abdominal wall-enables continuous urinary drainage, thereby maintaining a low-resistance drainage route and bypassing the urethra. In this way, excessive urine retention and high intravesical pressures can be avoided, approximating the concept of continuous low-pressure decompression used clinically during the early post-injury phase with suprapubic or transurethral urinary diversion, while recognizing that normal storage and continence mechanisms are abolished. Therapeutic effects that might otherwise be obscured by repetitive overfilling and high-pressure manual bladder expression may thus be more readily detected. Moreover, vesicostomy offers a conceptual strategy to mitigate sex-related constraints in preclinical SCI research. The considerably greater urethral length in male rodents results in higher outflow resistance, making manual bladder expression substantially more difficult and effectively confining most preclinical studies to female animals, despite the predominance of male patients among clinical SCI cases. As an alternative drainage strategy, vesicostomy has the potential to broaden experimental bladder management paradigms and enhance the translational relevance of future studies, while its feasibility and outcomes in male rats will need to be established in dedicated follow-up work.