To diagnose diverticulitis, it is important to do a barium enema X-ray to see the shape of the intestine wall. Diverticula can be seen with a axial tomographie scan (CT scan). It is also possible to prescribe an abdominal radiograph to indicate if there is a perforation. After the acute phase or absence of acute diverticulitis, the doctor can prescribe a colonoscopy to look at the colon and determine the evolution of the disease.