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This section serves as an introduction to the basic anatomy of the abdomen.
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The human gastrointestinal tract can be divided into upper and lower portions. All structures proximal to the ligament of Treitz can be thought of as the upper GI tract, while structures found distal to it are considered the lower GI tract. We will begin with axial sections depicting the upper abdomen, including the liver and stomach, and work inferiorly toward the pelvis (Figs. 5.1 through 5.9).
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