1240 THE DIGESTIVE SYSTEM. 



vestibule is continued beyond a fold termed the plica gastropancreatica into 

 the true bursa omentalis, which presents two main parts, the recessus superior and 

 recessus inferior. The recessus superior passes from the vestibule upwards behind 

 the porta hepatis to the dorsal surface of the lobus caudatus. Posteriorly it is in 

 contact with the diaphragm and aorta. The recessus inferior extends medially in 

 front of the pa*ncreas, and behind the stomach, and passes to the left towards the 

 spleen as the recessus lienalis. 



The recessus inferior omentalis and the vestibulum bursse omentalis communicate 

 with one another by a rounded orifice, which is constricted by the sickle-shaped 

 forward projecting fold, the plica gastropancreatica. This fold is an elevation of 

 the peritoneum of the posterior wall of the omental bursa, raised up by the 

 arteries of the stomach as they pass forwards to that organ from the posterior wall. 



As the peritoneal wall of the omental bursa is described in two main parts, 

 an anterior and a posterior, it will be necessary to follow each of these separately. 

 Above, the peritoneum forming the anterior wall clothes the caudate lobe ; it then 

 passes down (from the posterior margin of the porta hepatis, and the fossa of 

 the ductus venosus) to the lesser curvature of the stomach and the duodenum 



Small intestine 

 Greater omentum enclosing omental bursa | Mesentery 



Omental bursa 



Great sac 



Ascending colon 



Descending colon 



^^ _ 



Aorta Inferior vena cava 



FIG. 968. TRANSVERSE SECTION OF ABDOMEN THROUGH THE FOURTH LUMBAR VERTEBRAE. 



as the posterior layer of the lesser omentum. Continued on from this, it clothes 

 the posterior (or visceral) surface of the stomach as far as the greater curvature, 

 with the exception of the small "uncovered area" below and to the left of the 

 cardia (Fig. 969), but it does not actually come in contact with the oesophagus 

 itself, the back and right side of which are uncovered. On the left, it is reflected 

 from the back of the stomach to the spleen as the deeper layer of the gastro-splenic 

 ligament. 



From the greater curvature of the stomach it is continued down, forming the 

 posterior layer of the gastro- colic ligament as far as to the transverse colon. In 

 some cases it is not attached to the colon, but is continued onwards as the posterior 

 of the anterior two layers of the omentum, and in such cases at the inferior part 

 of the omentum it meets and becomes continuous with the posterior layer of the 

 omental bursa. 



The peritoneum forming the posterior wall of the bursa omentalis, in passing 

 through the epiploic foramen, clothes the front of the inferior vena cava (Fig. 969) ; 

 beyond this, it covers the coeliac artery, and passes upwards to line the slight 

 depression on the posterior abdominal wall (diaphragm), against which the caudate 

 lobe rests. Then, passing over to the left, it covers the superior surface of the 

 pancreas, the top of the left kidney and suprarenal gland, and the medial part of 

 the gastric surface of the spleen (Fig. 969). From the anterior border of the 



