Manovolumetric and sensory characteristics of the ileoanal J pouch compared with healthy rectum.

Abstract

Pouch volume, motility, sensory function and integrated pouch-anal mechanisms during graded isobaric distension of the pouch were prospectively studied in 67 patients with a J pouch-anal anastomosis. The findings were related to functional outcome. Thirty-six normal controls were studied for comparison. In contrast with normal rectum, the ileal pouch exhibited pronounced motility, and pouch contractions were frequent even at a high distension pressure. The presence of high pressure motility was associated with a poor functional outcome. The threshold pressure and threshold volume for eliciting first sensation of filling and urge to defaecate were significantly higher in the ileal pouch. The pressure threshold levels were not related to the functional outcome. Sphincter inhibition on pouch distension reappeared in 25 per cent of the patients. The distension pressure required to elicit the inhibition was considerably higher than in the control subjects. The functional result was similar irrespective of whether sphincter inhibition was present or not. The motor and sensory function of this artificial setting appear to be controlled by nervous mechanisms that are different from those in the healthy anorectum.