IS Case 353: Giant colonic diverticulum

Daniel Ginat, MD, MS

Imaging Sciences URMC


2009 URMC Imaging Sciences
Publication Date: 2009-11-09

History

Patient is a 72-year-old female presenting to the Emergency Department with abdominal pain and rectal bleeding.

Findings

CT scan revealed an encapsulated air-fluid collection adjacent to the sigmoid colon. A subsequent single contrast barium enema confirmed the diagnosis of a giant diverticulum of the sigmoid colon.

Diagnosis

Giant colonic diverticulum

Discussion

Giant diverticula are rare entities that mainly arise from the sigmoid colon. It is postulated that giant diverticula represent a complication of perforated diverticulitis in which there is a one-way-valve phenomenon that allows the cavity to enlarge. Only 13% are true diverticula, in which all the bowel wall components are present. Rather, most of these lesions are either inflammatory or pseudodiverticula, which comprise residual portions of bowel wall and granulation tissue or dense fibrotic tissue.

Giant colonic diverticula can be appreciated on plain film and CT as rounded air, fluid, or stool filled collections. Barium enema is diagnostic, with contrast filling the giant diverticula in about 60% of cases. However, it is believed that barium enema carries a risk of perforation. The main differential considerations include communicating duplication cyst and necrotic colon adenocarcinoma. However, duplication cysts tend to occur on the mesenteric aspect of the colon and necrotic carcinomas tend to have a thickened, nodular wall.

Surgical resection is generally the treatment of choice. While some attempts to perform diverticulectomy or percutaneous CT-guided drainage have been successful, there is a risk of recurrence.

References

  1. Thomas S, Peel RL, Evans LE, Haarer KA. Best cases from the AFIP: Giant colonic diverticulum. Radiographics. 2006 Nov-Dec;26(6):1869-72. PMID: 17102056
  2. Skucas J. Advanced Imaging of the Abdomen. Springer, 2006; 256.
  3. Steenvoorde P, Vogelaar FJ, Oskam J, Tollenaar RA. Giant colonic diverticula. Review of diagnostic and therapeutic options. Dig Surg. 2004;21(1):1-6; discussion 6. PMID: 14631129

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