[Urethral reconstruction with buccal mucosa and colonic mucosa onlay grafts: experiment with dogs].
OBJECTIVE
To investigate the possibility of urethral reconstruction with free buccal mucosa and colonic mucosa onlay graft.


METHODS
Twenty male mongrel dogs were randomly divided into 2 groups (n = 10 each). In group A: 4 cm x 0.8 cm segment of perineal urethra was excised and onlay urethroplasty was performed using free buccal mucosa. In group B: 4 cm x 0.8 cm segment of perineal urethra was excised and onlay urethroplasty was performed using free colonic mucosa. Retrograde urethrography was done at week 12. Autopsy specimens were calibrated with a 8Fr catheter. Graft length were measured immediately after scarification in all dogs. Histological study of all autopsy specimens was done.


RESULTS
Urethral structures were diagnosed by radiology and confirmed by calibration in 1 of the 10 dogs (10%) in group A and 2 of the 10 dogs (20%) in group B. Graft shrinkage was less than 20% for buccal mucosa and colonic mucosa. Histological examination revealed that the buccal mucosa and colonic mucosa survived inside the urethral lumen of all dogs. Plicae surface and unilaminar cylindric epithelium of the buccal mucosa and colonic mucosa were not observed and metaplastic transitional epithelium covered a large proportion of the urethral mucosa in all dogs.


CONCLUSIONS
Urethral mucosa can be replaced by colonic mucosa as well as buccal mucosa by using onlay urethroplasty.
Sa
Ying-long
YL
Department of Urology, Sixth People's Hospital, Shanghai Jiaotong University, Shanghai 200233, China.
Xu
Yue-min
YM
Chen
Bin-feng
BF
Liu
Feng
F
Liu
Zhang-shun
ZS
Feng
Chao
C
D000818:Animals; D004285:Dogs; D007413:Intestinal Mucosa / Q000637:transplantation*; D008297:Male; D023421:Models, Animal; D009061:Mouth Mucosa / Q000637:transplantation*; D011897:Random Allocation; D019651:Plastic Surgery Procedures / Q000379:methods; D013524:Surgical Flaps; D014521:Urethra / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods