258 THE DIGESTIVE SYSTEM 



in addition it encroaches to a slight extent upon the right 

 lumbar and the left hypochondriac regions (Fig. 92). 



The superior surface of the liver is in relation to the 

 inferior surface of the diaphragm, which separates it from the 

 right lung and pleural sac, the pericardium, and, to a much 

 lesser extent, from the left lung and pleural sac. Collections 

 of fluid in the right pleural sac or in the pericardium, or 

 enlargement of the right side of the heart (p. 297), may exert a 

 downward pressure on the liver and cause it to project below 

 the right costal margin for some distance. 



A similar downward displacement of the liver may be caused 

 by an infra-peritoneal subphrenic abscess^ situated in the recess 

 of the greater peritoneal sac which extends upwards and back- 

 wards between the upper surface of the liver and the inferior 

 surface of the diaphragm (Fig. 88). When the right lobe of 

 the liver is the site of a tropical abscess^ this peritoneal recess 

 may become obliterated by adhesions. As a result, if the 

 abscess burrows through the upper surface of the liver, it will, 

 in time, perforate the diaphragm and burst into the right pleural 

 sac or even into the lung itself. The latter complication can 

 only occur when the lung is adherent to the diaphragmatic 

 pleura, and the abscess is then evacuated by coughing. 



The anterior surface of the liver is roughly triangular in 

 outline, the apex being directed to the left and the base to the 

 right. The sharp lower margin of the liver, which forms the 

 inferior boundary of this surface, ascends obliquely as it passes 

 from right to left (PI. II.). In the subcostal angle, the anterior 

 surface of the liver is in direct contact with the deep surface of 

 the anterior abdominal wall, and it can therefore be examined 

 in this situation both by percussion and by palpation. 



On the right side, the anterior surface lies under cover of 

 the costal margin. In its upper part it is overlapped by the 

 pleural sac, and it is only in its lower part that it can be 

 approached without meeting with the pleura. On the left 

 side, the inferior border of the liver forms the right boundary 

 of Traube's space (p. 244). 



