Abdomen

the lower of the two cavities into the trunk of the human body is divided the diaphragm. Below, the abdominal cavity continuous with that of the pelvis (q.v.), the between She two being known as the brim. For convenience of reference, the is described as consisting of three an upper, middle, and lower, each zone again divided into three parts, thus forming regions in all. The epigastrium (A) is the region of the zone, having on side the right (B) left (c) hypo chon regions. In the zone is the um- (pb), bounded on side by the right and left (F) lumbar while the lowest presents laterally right (H) and left (1) ABDOMINAL REGIONS. regions, inc lud between them the hy- The liver lies mainly in the right but extends into the epigastrium; spleen is found in the left hypo chondri am; stomach occupies the epigastrium and part of left hypochondrium; and the pancreas is transversely acro the superior zone, lying in the epigastric or middle region, but exinto the lateral regions on either hand. two kidneys are situate in the right and left regions respectively. The cecum or first of the large intestine lies in the right inguinal and the su parts are the ascending 11 Abdominal i a. (7) colon, which pa es upwards through the right lumbar region, the transverse colon, which runs transversely acro the umbilical, the descending colon, which pa es through the left lumbar, and the sigmoid flexure which occupies the left inguinal region; the terminal portion, the rectum, being found in the pelvis. The convolutions of the small intestine occupy mainly the umbilical and hypogastric, but extend into the right and left lumbar regions. The abdomen is lined throughout by a serous membrane, the peritoneum (q.v.), which is reflected over the several viscera, and serves to maintain them in position. One of the chief surgical advances of modern times has been made in connection with ‘the abdomen. The operation of opening the abdominal cavity is now not infrequently undertaken for the relief of certain diseased conditions, and a large number of cases have now been conducted to a succe fyj i ue, which in former days would have been regarded as of too desperate a nature to admit of alleviation or cure.