Radiographic evaluation of spastic colon disease, diverticulosis, and diverticulitis.

Spastic colon disease is a syndrome consisting of abdominal pain and abnormal bowel function associated with thickening of the circular muscle layer of the colon. The condition may be related to changes in intraluminal pressure associated with a lifelong low residue diet. Radiologic features include thickening, crowding, irregularity, and distortion of the interhaustral folds of the sigmoid colon, which in the past have been incorrectly considered to be manifestations of acute diverticulitis. Spastic colon disease leads to diverticulosis which develops because of mucosal herniations through the weakened colonic wall. When a diverticulum perforates, acute diverticulitis ensues. Depending on how the subsequent inflammatory response is contained, a mural abscess, colonic narrowing or obstruction, an intra-abdominal abscess, or a fistula may occur and be demonstrated on barium enema examination.