THE ABDOMEN 693 



situated at the right extremity of the stomach. It is directed 

 backwards, and is guarded by the pyloric valve, which will be 

 described in connection with the structure of the stomach. Its 

 position is indicated superficially by the duodeno-pyloric constric- 

 tion already referred to. 



Divisions of the Stomach. — ^The stomach is divided into two parts 

 — cardiac and pyloric — by means of a line connecting the incisura 

 angtilaris on the small curvature with the opposite point on the great 

 curvature. The cardiac part lies to the left of this line, and is of large 

 size. It consists of the fundus and body of the stomach, the separa- 

 tion between these two parts being indicated by a line connecting the 

 cardia with the opposite point on the great curvature. The pyloric 

 part, which is short, is subdivided into two portions — namely, the 

 pyloric canal and the pyloric vestibule — ^by means of the sulcus 

 intermedius on the great curvature. The Pyloric canal adjoins the 

 duodeno-pyloric constriction. It is about i\ inches in length, and 

 is narrow and cylindrical in outline, hke a portion of the small 

 intestine. Its walls are thick, and it is directed backwards. The 

 pyloric vestibule, or antrum pylori, is a dilatation, situated to the 

 left of the pyloric canal, from which it is separated by the sulcus 

 intermedius. Its direction on the great curvature is downwards. 



Position of the Stomach. — When the stomach is empty it is com- 

 paratively small, which is due to the contracted state of its walls 

 during Ufe. It is situated horizontally in the left hypochondrium 

 and the left part of the epigastrium, emd is falciform in outUne. 

 The fundus is directed backwards; the cardiac portion, somewhat 

 saccular, is directed for%vards and sUghtly to the right ; the pyloric 

 portion, tubular in outhne, passes to the right; the pylorus Ues 

 about I inch to the right of the median Hue; the surfaces look 

 upwards and downwards; and the great curvature looks forwards, 

 and the small curvature backwards. 



When the stomach becomes distended, it usually assumes an 

 oblique position, its long axis being directed downwards, forwards, 

 and to the right. The organ increases in length; the pylorus is 

 carried towards the right side, assuming a position from i^ to 

 2 inches on the right side of the median plane; the pyloric canal 

 is bent backwards; the fundus becomes enlarged and directed 

 upwards and towards the left; and the upper surface acquires an 

 inclination forwcirds, and the under surface an inchnation back- 

 wards. The position of the cardia is practically unaltered. The 

 stomach still occupies the left hypochondrium and the epigastrium, 

 but, when much distended, part of it may enter the umbiHcal and 

 left lumbar regions. Occasionally the stomach, when distended, 

 retains the horizontal position occupied by it when empty. 



Topography of the Stomach. — The cardiac orifice, or cardia, is 

 situated to the left of the median Une about i inch below the sternal 

 attachment of the seventh left costal cartilage. It is about 4 inches 

 distant from the anterior abdominal wall, and is on a level with the 

 upper part of the body of the eleventh thoracic vertebra. 



