Figure 1c. Drawing of the anatomy of the greater and lesser omenta (a) and axial (b), coronal (c), and sagittal (d) diagrams of the upper abdomen. The greater omentum (GO) is composed of a double layer of peritoneum that extends from the greater curvature of the stomach (S) inferiorly. Its descending and ascending portions usually fuse to form a four-layer vascular fatty apron; the resulting space is contiguous with the lesser sac (LS). The lesser omentum (LO) connects the lesser curvature of the stomach and proximal duodenum with the liver (L) and contains blood vessels, nerves, and lymph nodes. The lesser sac is empty and collapsed so that only parts of its boundaries, such as the posterior gastric wall and pancreatic body, are observed on axial CT scans. Ao = aorta, C = colon, K = kidney, P = pancreas, Sp = spleen, 1 = falciform ligament, 2 = gastrohepatic ligament, 3 = gastrosplenic ligament.