Can a substitute for the bladder sphincter be attained by free transplants derived from vesical muscle tissue?

Smooth muscle transplants of the intestinal tract have been tested experimentally as a substitute for the bladder sphincter. An attempt was made to apply the proposed technique to the vesical muscle tissue and to achieve a sphincter replacement with freely transplanted autologous bladder tissue. An internal urethrotomy was performed several times in female sheep until a complete urinary incontinence resulted. For the bladder sphincter substitute a strip of vesical tissue was dissected from the anterior wall and following pre-stretching it was sewed circumferentially around the urethra in order to constrict it. The urethral pressure was registered during the operation before and after application of the sphincter 'graft'. For temporary urinary discharge a suprapubic catheter was inserted. The sheep were examined clinically and urodynamically for up to 3 months. Complete urinary continence was not obtained in any of the cases. The urodynamic examination showed a nearly complete loss of the urethral pressure which had been obtained by the operation. The histological studies showed progressing fibrosis of the desired continence zone. By way of freely transplanted autologous vesical muscle a sphincter substitute could not be achieved.