Abdomen



Abdomen




4.2 Use of Contrast in Abdominal Imaging Studies


Computed tomography can be performed with or without oral and/or intravenous (IV) contrast. Oral contrast helps the evaluation of the hollow viscera; agents include water, barium, and iodinated contrast. IV contrast is used to better evaluate the solid viscera, lesions, vasculature, and wall of the hollow viscera. Iodinated contrast is injected into a vein, usually an antecubital vein. It goes to the heart, to the lungs, and then to the aorta, which appears white from the contrast. In B, note that contrast has also reached arteries in the renal cortex, which is also white. As time goes by, the contrast is drained by veins in the organs, and everything becomes a little lighter shade of gray (C) compared to a noncontrast study. The contrast is filtered by the kidneys and opacifies the renal collecting systems, which become very bright (white) from the concentrated contrast (D).


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4.6 Pancreas Relationships


The pancreas has anatomical relationships that are clinically important and useful in the identification of structures in the abdominal foregut. The head of the pancreas lies in the curve of the duodenum, and its tail courses upward to the spleen. The celiac trunk originates just above the pancreas, and the splenic artery and vein follow the body and tail of the pancreas to the spleen, giving off numerous pancreatic branches along the way. The superior mesenteric artery originates immediately below the celiac trunk posterior to the neck of the pancreas. It appears medial to the head of the pancreas and passes anterior to the uncinate (“hooklike”) process, the most inferior extent of the pancreas. The portal vein is formed behind the pancreas by the union of the splenic and superior mesenteric veins. The common bile duct joins the pancreatic duct in the head of the pancreas to form the ampulla in the second part of the duodenum.


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Jan 10, 2016 | Posted by in RADIOGRAPHIC ANATOMY | Comments Off on Abdomen

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