THE LIVER 259 



SURFACE MARKING OF THE LIVER. When the outline of 

 the liver is determined by percussion on the anterior aspect 

 of the body, it is the anterior surface of the viscus which is 

 mapped out. Under normal conditions, with the patient in 

 the dorsal decubitus, the upper limit of the liver dulness 

 extends upwards into the fourth intercostal space on the right 

 side, but, owing to the thickness of the lung which intervenes 

 between the liver and the chest wall, it is not always easy to 

 determine the upper border with accuracy. Where the upper 

 surface of the liver is in relation to the heart, the limits of 

 the viscus cannot be determined by percussion. 



During quiet respiration, the upper border of the anterior 

 surface of the liver corresponds to a line drawn from a point 

 half an inch below and medial to the right nipple to a point 

 i inch below and medial to the left nipple. This line passes 

 through the xiphi-sternal junction and shows a slight downward 

 convexity, which corresponds to the lower border of the heart. 



The inferior border of the liver can easily be determined by 

 light percussion, which should be begun at some distance 

 below the costal margin. On the right side, the inferior 

 border coincides with the costal margin or projects a little 

 beyond it in the right lateral line, and, as it is traced to the 

 left, it ascends so as to cut the transpyloric plane in the median 

 plane. It then passes upwards more sharply, and crosses the 

 left costal margin opposite the tip of the eighth costal 

 cartilage (Stiles). 



In rare cases, a part of the right lobe of the liver, lateral to 

 the gall-bladder (p. 261), projects downwards, sometimes as far 

 as the iliac crest. It is termed Eeidel's lobe. The condition 

 is congenital and has no pathological bearing. Consequently, 

 care must be taken to avoid mistaking it for an abdominal 

 tumour. A similar downward projection may, very occasion- 

 ally, be found in connexion with the left lobe of the liver. 



In infants^ the inferior border of the liver usually lies at 

 least half an inch below the costal margin in the right lateral 

 plane. This difference is accounted for partly by the greater 



