الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Peripheral vascular disease is a common cause of morbidity all around the world. The prevalence is increased when sensitive noninvasive tests are used to make the diagnosis of arterial insufficiency in asymptomatic and symptomatic individuals. Until as recently as ten years ago, catheterdirected conventional angiography and digital subtraction angiography were the only angiographic techniques that provided sufficient anatomical details to allow surgical planning for patients with peripheral vascular disease. However it requires arterial puncture with its attendant complications. Furthermore, it can fail to demonstrate eccentric stenosis and patient discomfort associated with these techniques have prompted the need of a less invasive means of assessing the lower extremity arterial system. The purpose of noninvasive studies to provide information that can be combined with the clinical history and physical examination to form the basis for better assessment and making decisions regarding further treatment without making the patient suffering and reduce the hazard of invasive techniques and obtain nearly the same diagnostic results. Experience with CT angiography clearly shows that noninvasive testing can provide information comparable to that obtained by conventional angiography. CT angiography emerges as powerful minimally invasive alternative to catheter angiography for imaging the vessels of the lower extremity. The minimally invasive nature of this method, short examination time, and capability of threedimensional depiction of arteries, all make it and attractive alternative. Computed tomography angiography has been shown to be accurate in the investigation of a number of diseases, but long gantry rotation period and slow table speed limited the performance of CT angiography with singledetector scanners to relatively small anatomical areas. Multidetector row CT scanners (MDCT) allow imaging over craniocaudal lengths exceeding 1.5 meter. Imaging of the entire arterial supply of the lower extremities in a single helical acquisition is possible by MDCT. In clinical applications the advantages derived from MSCT technology ca be summarized in: a) Improved scan speed which allows better coverage in a single breath hold, provides a significant reduction in patient movement artifacts and encourages better use of contrast media. b) Availability of isotropic imaging. It is defined as identical resolution of a structure in all dimensions. This valuable feature is of importance in 3D imaging, where stair step artifacts are virtually eliminated and the anatomical edges are well defined.