Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients

Figure 2 The 5-layer structure of the normal gastric wall on ultrasonography. The 5-layer structure of the normal gastric wall is numbered from the luminal side. Layer 1 is the interface echo between the gastric lumen and the mucosa, layer 2 is the rest of the mucosa, layer 3 is the submucosa, layer 4 is the muscularis propria, and layer 5 is the serosa.