**4.1 Noninvasive evaluation**

Duplex ultrasonography is a useful tool for the early, noninvasive diagnosis of visceral ischemic syndromes. Color Doppler scanning can be used to assess the flow velocities and resistance index in the splanchnic arteries and their arterial beds, as well to evaluate endorgan vascularity (12).

Computed tomography (CT) is an accurate, noninvasive imaging modality for diagnosing mesenteric ischemia, CTA diagnosed AMI with a sensitivity of 96% and a specificity of 94%.

Magnetic resonance angiography (MRA) is useful for diagnosing mesenteric occlusive disease. Because MRA takes significantly longer to perform than CTA, its role in evaluating patients with AMI is limited.

## **4.2 Invasive evaluation**

Conventional angiography remains the "gold standard" in the diagnosis of mesenteric ischemia. Anteroposterior and lateral views of the visceral aorta as well as selective catheterization of the celiac trunk, SMA, and IMA, provide the most accurate and specific localization of stenotic and occlusive lesions. Therapeutic alternatives such as balloon angioplasty, stenting, and thrombolysis and percutaneous thrombus extraction can all be used to restore luminal visceral blood flow.
