الفهرس 
Introduction
Technological advancement of computedOnly 14 pages are availabe for public view
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Abstract
One of the goals of modern medicine is to achieve an accurate and early diagnosis, as well as determine optimal treatment and achieve reduced mortality in patients with mesenteric ischemia. This is often difficult, however, because of the variable clinical and radiologic-pathologic manifestations of the condition (Weisner et al,. 2003). Therefore, a strongly clinical-radiologic approach must be pursued in the detection, diagnosis, and treatment of this often fatal disease. Indeed, understanding of bowel ischemia and its various causes and pathogenesis and detailed information about the clinical setting of each patient are often important factors in the establishment of an accurate CT diagnosis (Rosow et al., 2005). Traditional angiography is the diagnostic gold standard but is invasive and costly. CT is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of MSCT greatly facilitates the use of CT angiography (CTA) in the clinical setting (Rosow et al., 2005). Due to several distinct advantages over conventional angiography (including minimal invasiveness, lower cost, and lower ionizing radiation exposure for patients and staff), MSCTA has replaced diagnostic conventional angiography in several clinical situations. The recent introduction of MSCT scanners has significantly improved CT angiographic applications, especially in the evaluation of the mesenteric vasculature. Thin-slice collimation protocols associated with powerful postprocessing procedures allow the display of mesenteric circulation with excellent detail (Laghi et al,. 2004). MDCT angiography is an established non-invasive imaging modality to evaluate the mesenteric vasculature (Wildermuth et al., 2004). Mesenteric MSCTA is a useful tool for visualizing normal vascular anatomy, its variants and Vascular pathology (Fleischmann, 2003). It has an important role in diagnostic algorithms for assessment of suspected acute and chronic mesenteric ischemia (Hellinger, 2004). The diagnostic accuracy of MSCT for the prospective diagnosis of acute bowel ischemia was analyzed by Weisner et al., and found that the prospective sensitivity and specificity for the diagnosis of acute bowel ischemia were 79.17 and 98.51%. MSCT reaches a similarly high sensitivity in diagnosing acute bowel as angiography. Furthermore, it has the advantage of being helpful in most of its clinical differential diagnoses and of being less invasive with the consecutive possibility of being used earlier in the diagnostic process with all the resulting positive effects on the patients prognosis. Therefore, nowadays MSCT should probably be used as the first step imaging modality of choice in patients with suspected acute bowel ischemia (Weisner et al,. 2004). The development of MSCT technology has overcome past limitations. First, the faster scanning speed increases volume coverage during a single breath-hold and improves the exploitation of contrast medium. Second, the better spatial resolution results in nearly isotropic voxels allowing reconstruction of high-resolution three-dimensional images with different algorithms. Volume rendering is capable of displaying the visceral vasculature from any external vantage point. Compared to conventional angiography, MSCTA not only delineates vessels but also depicts the anatomical relationship to adjacent structures and allows the evaluation of perfused organs. MSCTA also has become an emerging tool for the pre- and postinterventional assessment of vascular anatomy (Wildermuth et al., 2004).