Gastric wall layer

Fig. 17.4. Preserved gastric wall layers with an echo-intense thickening of the submucosal layer measuring 5.2 mm (crosses) after antibiotic treatment for Helicobacter pylori in a patient with low-grade gastric MALT-NHL...

Lubienski A, Grenacher L, Reith Wet al (2002) MR-imaging of gastric wall layers in vitro correlation to the histologic wall structure. Fortschr Rontgenstr 174 490-494... 

The normal gastric wall is demonstrated as a five-layer structure. The first layer is hyperechoic, and corresponds to the luminal boundary and part of the mucosal layer. The second layer is hypoechoic and includes the remaining part of the mucosa and mucosal muscle layer. The third layer is hyperechoic and corresponds to the submucosal layer. The fourth layer is hypoechoic and corresponds to the proper muscle layer. The fifth layer is hyperechoic and corresponds to the serosa and the extramural boundary. 

Fig. 16.1. Transverse scan of the gastric body. The five-layer structure of the gastric wall and the gastric fold are demonstrated...

Fig. 17.2. Thickening of the submucosa with preserved layers of the gastric wall in a patient with MALT-NHL stage II...

EUS may be useful in detecting lymphoma tissue in deeper layers of the gastric wall not responding to treatment however, EUS is quite inaccurate in demonstrating early response or detecting minimal residual disease (POspSk et al. 2002 BayerdSrffer et al. 1995). EUS. nevertheless, should remain part of... 

Fig. 19.11. a Extramural compression of the gastric wall by the spleen. An elevated area due to compression of spleen is shown, b Endosonographic feature of the extramural compression by a liver cyst (/c). The normal live-layer structure is observed at the elevated area. Ao aorta... 

Within the stomach an acidic environment exists, with a pH between 1.5 and 3.0 (with extremes between 1.0 and 5.0). In addition, digestive enzymes are present. The residence time in the stomach depends on the nutritional status and on the physical form of the medicine and may be highly variable. An active substance in solution, taken on an empty stomach, will pass the stomach quickly, usually within 30 min. A non-disintegrating large tablet, taken after a high-fat meal, may remain in the stomach for several hours. Absorption from the stomach plays a minor role in the total absorption, because of the relatively small surface of the gastric wall in relation to the stomach volume and the thickness of mucus layer and membrane. 

Table 8-2. Distribution of Small and Large Microspheres in the Layers of the Gastric Wall of the Dog s Stomach...

T2 transmural enhancement with focal wall thickening in a single layer pattern, or both abnormal enhancement and abrupt obliteration of middle in three-layered pattern, or outer layers in two-layered pattern. Smooth outer border of thickened gastric wall or few small linear strands of soft tissue extending into fat plane... 

It has shown promising results, especially in tumour staging. Experimental MR studies have shown that depiction of the anatomic layers of the gastric wall is possible, and it is well accepted that endoscopic MR examinations of the stomach may have the potential for visualization of gastric disease (Auh et al. 1994 Oi et al. 1997 Yamada et al. 2001 Lubienski et al. 2002). 

MRI has recently been used for the visualization of gastric tumours. In gastric carcinoma tumourous infiltration of the serosa may be shown by conventional MRI (Matsushita et al. 1994 Oi et al. 1997), but accurate local staging of gastric carcinoma by MRI requires reliable interpretation of the wall layers. This may be achieved by high-spatial-reso-... 

At MRl, a focal thickening together with marked contrast enhancement and disruption of the layered pattern of the gastric wall are suspicious of gastric carcinoma (Matsushita et al. 1994 Chou et al. 1994 Oi et al. 1997). Thus CT and US criteria can be... 

Fig. 7.4. Endoscopic MR imaging of the stomach. The receiver coil (arrowheads) was advanced into the lumen of the stomach and covers an area of 9-10 cm that can be used for imaging. A small early gastric carcinoma (arrow) is located within the gastric wall and has infiltrated the submucosa. The submucosa is represented by the middle, hypointense layer of the gastric wall ( )...

Mucus is produced by the mucus neck cells and by the surface epithelial cells of the stomach wall. A thick layer of mucus adheres to the wall of the stomach, forming the gastric mucosal barrier. The function of this barrier is to protect the gastric mucosa from injury — specifically, from the corrosive actions of HCl and pepsin. Together with bicarbonate ion released into the lumen of the stomach, mucus neutralizes the acid and maintains the mucosal surface at a nearly neutral pH. 

Food is propelled through the stomach by wall contraction in a similar manner to the way blood is pushed through blood vessels. The stomach and intestines contain several layers including the mucosa, submucosa, muscu-laris, and serosa. In the stomach the inner lining is made up of a mucous layer with columnar epithelium that extend into the gastric pits about 1/4 of the thickness of the wall (Figure 3.14). Below the epithelium is the lamina... 

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