الفهرس 
anatomy of the pancreasOnly 14 pages are availabe for public view
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Abstract
Pancreatic adenocarcinoma is a common gastrointestinal malignancy that has a poor prognosis and for which successful surgical resection is the only method of cure. The role of single slice CT in early detection of the pancreatic cancer was not enough before the ear of MDCT . In detection and staging of pancreatic ductal adenocarcinoma, MDCT had a sensitivity of more than 90% and a positive predictive value in the range of 96% to 100% for determining surgical Unresectability. The major advantage of MSCT over single-detector spiral CT is substantial improvement in the speed of scan acquisition, which permits routine use of very thin collimation covering a large region during single breath-hold to acquire volumetric data sets with high resolution The improvement of resolution is very helpful for generating high quality multiplanar reformations (MPR) and 3D images. An examination protocol should provide maximal differentiation between normal and abnormal tissue. A challenge of pancreatic imaging is that the timing of peak pancreatic enhancement differs from that of other organs in the abdomen, most notably is the liver. Therefore a pancreatic imaging protocol should specify the timing of acquisitions that coincide with the peak enhancement of the organs of interest. In the assessment of pancreatic tumors, there are four basic components: (a) Detection of the pancreatic tumor itself; (b) Assessment of peripancreatic arteries; (c)Assessment of peripancreatic veins; (d) Detection of extra pancreatic metastases (most frequently the liver). The pancreas is supplied by multiple end arteries arising from the celiac axis and the superior mesenteric artery, whereas the liver is supplied predominantly by the portal vein. Although arteries are homogeneously enhanced during the peak of pancreatic enhancement, the peripancreatic venous structures may not be homogeneously enhanced until a time near the peak of hepatic enhancement. Because of this discrepancy in organ/vascular opacification, the use of the dual-phase protocol which incorporates a pancreatic parenchymal phase and a portal venous phase is defiantly the best technique. MDCT examinations have been successfully the most accurate method of early detection and staging of pancreatic cancer with detection of small metastatic lesions. This was of a great value to surgeons to avoid unnecessary maneuvers, which subsequtally decrease death rate.