Histopathological evaluation of the urethra after the Snodgrass operation: an experimental study in rabbits

To investigate the histopathological outcome of the incised urethral plate after tubularized incised-plate urethroplasty (the Snodgrass procedure to repair hypospadias) in a hypospadiac rabbit model, as it can produce meatal and neourethral strictures, and healing with scarring.

The study comprised 10 male New Zealand White rabbits (2.2-2.4 kg); under general anaesthesia the ventral urethra was completely excised 1 cm from the meatus proximally and a model of hypospadias formed. A full-thickness incision was then made in the distal dorsal urethra and the two sides of the incision marked by Indian ink tattooing. After placing a feeding tube (5 F) as a urethral catheter, both urethral wings were sutured ventrally by a 7/0 polydioxanone running suture, and the penile skin approximated by 5/0 chromic catgut. At 21 days and 3 months after surgery the penises were harvested, assessed histopathologically, and compared with those from control untreated rabbits of the same age and weight.

In the study group the incised area of the dorsal urethra was re-epithelialized; the regional tissue and vascularity were normal.

In this rabbit model the dorsal urethral incisions healed with no scar tissue; only the ventral suture lines had minimal fibrosis and inflammatory reaction.