Non-obstructive colonic dilation: radiologic findings in 50 patients following colonoscopic treatment.

Fifty patients with acute onset of colonic dilatation without mechanical obstruction were evaluated before and after colonoscopic decompression. Colonic dilatation, as demonstrated radiographically, was segmental or consistent with mechanical obstruction in 33 (66%). Signs of impending cecal perforation were seen in five (10%) and these patients had colonoscopic decompression, tube cecostomy, or both. Following colonic decompression, cecal diameter may remain unchanged for two to four days, despite decreased abdominal girth and even shortening of the colon radiographically. Improvement in pain, distention, tenderness, fever and leukocytosis may precede radiographic improvement. The radiologist must recognize this entity, look for signs of impending perforation and signs of bowel shortening, with or without decompression after treatment. Barium studies of the colon should be avoided since they can hamper the endoscopic diagnosis and treatment of colonic dilatation.