Nonocclusive Mesenteric Ischemia

Nonocclusive mesenteric ischemia is an acute syndrome of low superior mesenteric flow in the absence of a fixed obstruction. It is seen most commonly in ICU patients on vasopressors or digitalis or in patients in septic or cardiogenic shock.

Angiography is the gold standard diagnostic modality and demonstrates:

• Slow flow in the superior mesenteric artery
• Diffuse narrowing of the superior mesenteric artery branches with interspersed areas of normal caliber vessels ("string of sausages" sign).
• Poor filling of the vasa recta
• Spasm of the marginal artery of Drummond and other branch points
• Persistence of contrast enhancement of intestinal branches for longer than 2 seconds after injection.

When suspected, vasodilators can be injected to counteract the spasm. And continuous intra-arterial infusion of papaverine, prostaglandin E₁, or nitroglycerine can be used for treatment.

CT will show diffuse severe narrowing of the mesenteric arteries or branches with segmental stenoses and dilations.

References

• Ofer A, Abadi S, Nitecki S, Karram T, Kogan I, Leiderman M, Shmulevsky P, Israelit S, Engel A. Multidetector CT angiography in the evaluation of acute mesenteric ischemia. Eur Radiol. 2009 Jan;19(1):24-30.
• Mitsuyoshi A, Obama K, Shinkura N, Ito T, Zaima M. Survival in nonocclusive mesenteric ischemia: early diagnosis by multidetector row computed tomography and early treatment with continuous intravenous high-dose prostaglandin E(1). Ann Surg. 2007 Aug;246(2):229-35.