Proximal urethral reconstruction using a distally based ventral bladder tube flap. An experimental study

Area of Science:

• Veterinary Surgery
• Urology
• Regenerative Medicine

Background:

• Total prostatectomy and urethral resection can lead to significant proximal urethral defects in dogs.
• Reconstructing these defects is crucial for maintaining urinary function and quality of life.
• Existing techniques may have limitations in achieving tension-free anastomosis and functional recovery.

Purpose of the Study:

• To evaluate the efficacy of a distally based ventral bladder tube flap for proximal urethral reconstruction in dogs.
• To assess the surgical technique's feasibility, vascular integrity, and functional outcomes.
• To determine the potential for urodynamic recovery after this reconstructive procedure.

Main Methods:

• Twelve clinically normal dogs underwent total prostatectomy and 2 cm membranous urethral resection.
• A distally based tube flap was mobilized from the ventral bladder wall for urethral reconstruction.
• Postoperative evaluation included assessment of flap vascularity, urinary continence, dysuria, and urethral closure pressure profilometry.

Main Results:

• Tension-free anastomosis to the membranous urethra was achieved in all cases.
• Vascular integrity of the flaps was maintained throughout the study.
• Postoperative urinary incontinence (7/10 dogs) and dysuria (8/10 dogs) were observed, primarily transient, with most resolving by 6-12 weeks.
• Urethral closure pressure profilometry revealed decreased membranous urethral tone in long-term survivors.

Conclusions:

• Ventral bladder tube flap reconstruction is a viable surgical option for proximal urethral defects in dogs.
• The technique facilitates tension-free anastomosis and maintains flap vascularity.
• While temporary functional deficits like incontinence and dysuria may occur, the potential for functional urodynamic recovery exists.