[Construction of a neorectum after rectal excision: colonic pouches]

Rectal excision followed by low anastomosis is associated with high bowel frequency, urgency and faecal incontinence. These functional disorders results from the loss of the rectal pouch and may be also related to the damage of the anal sphincter or the loss of normal anorectal sensation. Formation of a colonic J pouch reduces the severity of the symptoms of the anterior resection syndrome mainly by decreasing bowel frequency. Creation of a J pouch may also improve the healing of coloanal anastomoses. However, there is no evidence of the role of the colonic J pouch in long term functional outcome of coloanal anastomoses. Moreover, the size of the J pouch increases with time and this may induce evacuation difficulties. Finally, the J pouch cannot be used in all patients, because of technical difficulties especially in obese men. Because the results after colonic J pouch are not perfect, new colonic pouches are developed. The caecal pouch is performed by using an ileocoecal interposition graft between the sigmoid and the anus. The transverse coloplasty is similar to that of stricturoplasty. The side-to-end coloanal anastomosis, giving a colonic blind end, is an other type of pouch. The first procedure seems technically complex with no demonstrated advantage. The second procedure is easy to construct and may be performed in all patients; however, there is a potential higher risk of leakage and functional results must be evaluated. The third procedure showed few advantages compared to a straight anastomosis.