After taking a thorough history, the diagnosis of colonic volvulus is usually easily included in the differential diagnosis. Abdominal plain x-rays are commonly confirmatory for a volvulus, especially if a
coffee bean sign is seen. These refer to the shape of the air-filled closed loop of the colon, which forms the volvulus. Should the diagnosis be in doubt, a barium enema may demonstrate a "bird's beak" at the point where the segment of proximal bowel and distal bowel rotate to form the volvulus. This area shows an acute and sharp tapering and looks like a bird's beak. If a perforation is suspected, barium should not be used due to its potentially lethal effects when distributed throughout the free intraperitoneal cavity.
Gastrografin, which is safer, can be substituted for barium. The differential diagnosis includes the much more common constricting or obstructing carcinoma. In approximately 80 percent of colonic obstructions, invasive carcinoma is found to be the cause. This is usually easily diagnosed with endoscopic biopsies.
Diverticulitis is a common condition with different presentations. Although diverticulitis may be the source of a colonic obstruction, it more commonly causes an ileus, which appears to be a colonic obstruction. Endoscopic means can be used to secure a diagnosis, although this may cause a perforation of the inflamed diverticular area. CT scanning is the more common method to diagnose diverticulitis. The scan will show mesenteric stranding in the involved segment of edematous colon, which is usually in the sigmoid region. Microperforations with free air may be seen. Ulcerative colitis or
Crohn's disease may cause colonic obstruction. The obstruction may be acute or chronic, and after years of uncontrolled disease, it leads to the formation of strictures and fistulas. The medical history is helpful in that most cases of inflammatory bowel disease are well known to both the patient and doctor. Other rare syndromes, including
Ogilvie's syndrome, chronic constipation, and impaction, may cause a pseudo-obstruction. •
Abdominal x-ray – tire-like shadow arising from the right iliac fossa and passing to the left •
Upper GI series File:Sigmavolvulus - Coffee-bean-sign - LSL.jpg|Coffee bean sign in a person with sigmoid volvulus File:Sigmavolvulus - 91w - CT cor - 001 - Annotation.gif|Coronal view of sigmoid volvulus with "whirlpool sign" File:CT of small bowel volvulus (annotated).jpg|
CT scan of a small bowel volvulus. It shows two juxtaposed segments of narrowing, which is the spot of mesentery rotation. The other signs indicate strangulation. File:Voluculus.PNG|An x-ray of a person with a
small bowel volvulus. File:CecalVolvulusXray.png|Plain X ray of a cecal volvulus File:CecalVolvulus.png|CT scan of a cecal volvulus ==Treatment==