الفهرس 
Normal anatomy of bowel loopsOnly 14 pages are availabe for public view
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Abstract
SUMMARY AND CONCLUSION
Mesenteric ischemia is an emergency disorder. Arterial embolism accounts for approximately one third of acute cases of AMI. Emboli to the mesenteric arteries are usually from a dislodged cardiac thrombus. The SMA is most commonly affected while the IMA rarely affected due to its small caliber. Arterial thrombosis accounts for approximately one third of acute cases of AMI. It is usually due to acute worsening of ischemia in patients who have preexisting atherosclerosis of the mesenteric arteries.
Findings of AMI included mesenteric arterial or venous thrombus, mesenteric venous gas, pneumatosis intestinalis, bowel-wall thickening, increased or decreased enhancement of the bowel wall, bowel dilatation, mesenteric or perienteric fat stranding, ascites, pneumoperitoneum, and solid organ infarction are easily detected by MSCT.
Non occlusive etiology accounts for approximately one third of acute cases of AMI. The primary mechanism is severe and prolonged intestinal vasoconstriction. The most common setting is severe systemic illness with systemic shock usually secondary to reduced cardiac output.
Chronic mesenteric ischemia usually results from long-standing atherosclerotic disease of 2 or more mesenteric vessels. Symptoms are caused by the gradual reduction in blood flow to the intestine that occurs during eating since total blood flow to the intestine can increase by 15% during meals.
MSCT and 3-dimensional imaging provide a detailed examination of small bowel and the mesenteric vessels and is a valuable tool for the evaluation of mesenteric ischemia.
MSCT technology with the faster scanning speed increases volume coverage during a single breath-hold. Moreover, with the better spatial resolution, allows reconstruction of high-resolution three-dimensional images. Postprossing and reconstruction techniques such as VR, MIP, SSD is capable of displaying the visceral vasculature from any external point. MSCTA not only delineates vessels but also shows the anatomical relationship to adjacent structures. MSCTA also has become an emerging tool for the pre- and post interventional assessment of vascular anatomy.
Mesenteric MSCT angiography is a non-invasive tool for visualizing normal vascular anatomy, its variants and vascular pathology. It has an important role in diagnosis of suspected cases of acute and chronic mesenteric ischemia.
MSCT is also more helpful than DSA in ruling out extrinsic causes of vessel obstruction e.g., vessel encasement or compression by lesions.
CONCLUSION
Computed tomography angiography (CTA) of the abdomen with multiple detector-row computed tomography (MSCT) is an effective technique for minimally invasive imaging of the visceral vasculature. Mesenteric CTA is a useful tool for visualizing normal vascular anatomy and its variants. Vascular pathology, e.g. atherosclerotic disease or aneurysms of the visceral arteries