362 CLINICAL APPLIED ANATOMY. 



The position of the pylorus is best defined by the transpyloric 

 line. This is a horizontal line which bisects the distance between 

 the episternal notch and the top of the pubic symphysis. The 

 pylorus normally lies in this line, being practically mesial if the 

 stomach is empty but lying two or three inches to the right if 

 the viscus is distended. 



The weight of the dilated stomach tends to depress that 

 part of the stomach bed which is formed by the transverse 

 colon and mesocolon. The stomach may thus indirectly exercise 

 enough pressure on the duodeno-jejunal flexure or the terminal 

 portion of the duodenum to obstruct the passage of its own 

 contents. 



Prolapse of the stomach, or gastroptosis, may also be a cause 

 of dilatation, a sharp bend being formed at the superior duodenal 

 flexure through the agency of the peritoneal ligaments attached 

 at this spot. The stomach is normally retained in its position 

 in the stomach bed not only by the support of the muscular 

 walls of the abdomen and the structures which form the bed, but 

 also by strong ligamentous bands. At each end of the lesser 

 curvature vertical and horizontal ligamentous supports are 

 attached. The left support is formed by the firm attachment 

 of the cardiac end to the diaphragm in the neighbourhood of the 

 cesophageal opening, by the adjacent gastro-phrenic omentum 

 which passes vertically, and by the left pancreatico-gastric fold, 

 which is horizontal. The pancreatico-gastric fold is continuous 

 with the gastro-phrenic omentum and conveys the coronary 

 artery to the stomach. The right support is also a double fold ; 

 this is attached not to the stomach but to the first curvature of 

 the duodenum. It consists of the vertical hepato-duodenal 

 ligament, which is the right free edge of the lesser omentum 

 and the horizontal pancreatico-duodenal fold which passes from 

 the region of the head of the pancreas forwards .to join the 

 duodenum at the same point as the hepato-duodenal ligament, 

 the two becoming continuous. The central portion of the lesser 

 omentum is of extreme tenuity and obviously of no importance 

 as a gastric support. The main factors are the strong ligaments 



