Applied Radiology

Diagnosis

Cecal volvulus

Findings

The initial abdominal films showed an ectopic cecum in the left upper quadrant measuring 12.6 cm in diameter (figure 1). Films taken 36 hours later demonstrated the transverse dimension of the cecum to have increased to 16 cm; 40 hours following admission the cecum had reached 20 cm in diameter. Despite a radiological diagnosis of cecal volvulus, a contrast enema was requested for confirmation. The cecum could not be filled and findings confirmed the suspected plain film diagnosis of cecal volvulus (figure 2). No attempt was made to reduce the volvulus.

At surgery, the cecum was intact but grossly distended with visually apparent infarction. The cecum was resected, and a right hemicolectomy was performed with a distal ileal resection and ileal transverse colonic anastomosis. Pathologic analysis confirmed an infarcted and gangrenous cecum.

Discussion

It has been reported that cecal distention of more than 10 to 12 cm places the patient at high risk for bowl perforation.¹ In this case the cecal distention significantly exceeded this degree of distention and resulted in infarction without perforation.

Colonic volvulus represents 10% of cases of large-bowel obstruction, and cecal volvulus represents approximately 40% of all such cases.^2,3 Cecal volvulus occurs predominantly in patients with poor right colon fixation and affects approximately 10% to 25% of the population.⁴ Such poor fixation leads to excessive cecal mobility and the potential for vascular compromise, which may occur as a result of intestinal dilation and vascular torsion. Torsion of the cecum takes place for a number of reasons: sudden distention of the cecum by trauma, pressure, constipation, or a distal colonic obstruction.^5-7

Cecal volvulus can be diagnosed in 50% of the cases on the basis of abdominal series alone. If the positive diagnosis is not made on review of the abdominal series, follow up-films or contrast enema are required. In this case, the duration of the observation over 40 hours represented a fulminant course which may have accounted for a lack of frank perforation.

Two types of cecal volvulus have been described. Type I cecal volvulus, sometimes called cecal bascule, occurs when the cecum rotates anteriorly to the ascending colon. Type II cecal volvulus occurs when the cecum abnormally rotates into the left upper quadrant. Perret and Kunberger¹ have described a case of Type II cecal volvulus. These authors suggest that a cecal diameter >10 to 12 cm is an ominous sign and may indicate impending perforation.

There are two major scenarios in clinical cecal volvulus. The first, fulminant, with strangulation and the mesenteric torsion causing arterial and venous obstruction, occurs coincidentally with the rotation.⁸ The second form has the prominent feature of the bowel obstruction with vascular compromise occurring gradually due to an increased distention and intraluminal pressure in the cecum that interferes with blood supply to its wall. Perforation occurs in 65% of cases where there is a mechanical distention combined with a vascular compromise. Perforation results in a life-threatening complication associated with a mortality of 20%.⁷ When associated with cecal gangrene, the postoperative mortality is reported to be as high as 45%.⁵ It has been suggested that the duration of the cecal distention is as significant as the absolute size of the cecum.^6,7

This patient demonstrated signs of abdominal compartment syndrome (ACS), which is an organ dysfunction due to increased abdominal pressure with secondary compromised respiratory functions and decreased cardiac output. The syndrome is a life-threatening complication of massive bowel distention.⁹ It is important to note that this clinical condition is associated with decreased cardiac function, poor ventilation and retention of CO₂, as in our patient. That clinical finding can be seen in a number of conditions, including trauma, hemorrhage, pancreatitis, liver transplantation, and other insults resulting in increased pressure in intra-abdominal organs but without the radiological features of the cecal volvulus. In cases of cecal volvulus with these clinical findings, surgical intervention is warranted.

CONCLUSION

In summary, our case confirms that rapid cecal distention is a warning sign of an impending perforation. The radiological findings of distended cecum and the constellation of associated clinical findings are critical in planning therapeutic intervention.

1. Perret R, Kunberger L: Cecal volvulus. AJR Am J Roengenol 171:860-861, 1998.
2. Nelson TG, Bowers WF: Volvulus of the cecum and sigmoid colon: An analysis of nine cases. Arch Surg 72:469-478, 1956.
3. Spiro H: Clinical Gastroenterology, pp 758-759. New York, McMillan, 1983.
4. Rogers RL, Harford FJ: Mobile cecum syndrome. Dis Colon Rect 27:399-402, 1984.
5. Tejler G, Jiborn H: Volvulus of the cecum. Report of 26 cases and review of the literature. Dis Colon Rect 31:445-449, 1988.
6. Smith WR, Goodwin JN: Cecal volvulus. Am J Surg 126:215-222, 1973.
7. Johnson CD, Rice RP, Kelvin FM, et al: The radiological evaluation of gross cecal distention. Emphasis on cecal ileus. AJR Am J Roentgenol 145:1211-1217, 1985.
8. Hinshaw DB, Carter R, Joergenson EJ: Volvulus of the cecum or right colon: A study of fourteen cases. Am J Surg 98:175-183, 1959.
9. Eddy V, Nunn C, Morris JA, Jr: Abdominal compartment syndrome. Surg Clin North Am 77:801-812, 1997.