Rectosigmoid colon

Fig. 23.4. Distribution of resin labeled with 111 In after four successive daily (morning) administrations among a cohort of normal volunteers and patients with active colitis. AC, ascending colon DC, distal colon RS, rectosigmoid colon TC, transverse colon.

In terms of size and complexity, the human colon falls between that of carnivores, such as the ferret which have no discemable jrmction between ileum and colon, and herbivores like the rat, which has a voluminous cecum. The cecum, colon ascendens, colon transversale, colon descendens, and rectosigmoid colon make up the colon. It... 

Fig. 1.30a-e. Hirschsprung disease. Supine (a), upright (b) and lateral (c) plain radiographs show distension of the bowel corresponding to a low obstruction, with air-fluid levels in the upright film and absence of gas in the rectum in the lateral film. d,e Contrast enema shows a distended colon and an obvious zone of transition (arrows) in the rectosigmoid junction. The caliber of the rectum is very small... 

Fig. 1.31a,b. Hirschsprung disease. a Contrast enema shows a distended colon and a small rectum and portion of the colon. The rectosigmoid index is abnormal. b Intraoperative photograph demonstrates the transition zone (arrows) with the shape of an inverted cone... 

Fig. 1.32a-d. Total colonic agan-glionosis. a Plain radiograph of the abdomen demonstrates low obstruction. b,c Anteroposterior and lateral views during contrast enema show the shortened colon compared with the normal redundancy of the neonatal colon, with the flexures pulled down and a normal rectosigmoid index, d Intraoperative photograph shows dilated bowel loops with the transition zone at the distal ileum... 

Fig. 1.34. Small left colon syndrome. Isosmolar water-soluble contrast enema in a newborn with low obstruction demonstrates a normal rectum and distal rectosigmoid and a relatively narrow proximal sigmoid and descending colon with a transition to a more dilated colon at the splenic flexure. In 1 week radiographic and clinical signs of obstruction resolved...

The electrical rhythmic adivity in canine stomach [Sarna et al., 1972], canine smaU intestine [Nelson and Becker, 1968 Diamant et al., 1970 Sarna et al., 1971], human smaU intestine [Robertson-Dunn and Linkens, 1974], human colon [Bardalgian and Sarna, 1980], and human rectosigmoid [Linkens et al, 1976] has been modeled by populations of coupled nonlinear osciUators. The interaction between coupled nonlinear osciUators is governed by both intrinsic osdUator properties and coupling mechanisms. 

Ulcerative cohtis involves the rectum and extends proximally to all or different portions of the colon (ulcerative proctitis, sigmoiditis, left-sided cohtis or pancolitis). Rectosigmoid involvement is present in almost all patients at endoscopy, with approximately 40-50%ofpatientshavingdiseaselimitedtotherectum... 

Posterior tumor growth leads to infiltration of the presacral space and sacral bone or of the perirectal space and rectum. Recurrent cervical cancer is associated with rectal infiltration in about 17% of cases. The most common site is the rectosigmoid junction. Laterally, recurrent tumor may extend to the pelvic sidewall. If the recurrent local tumor grows anteriorly along the peritoneal fold, there will be infiltration of the urinary bladder. Advanced recurrent cervical cancer may involve the remaining colon or the small intestine and is typically associated with adhesion of bowel loops and may cause intestinal obstruction. 

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