534 



HUMAN ANATOMY. 



Dyspepsia. 

 Morning Vomltino 

 Hematemesit 



obstructive cause, as do many cases of varicose veins of the lower extremity, and 

 may be very large and extremely tortuous {caput viedustz). 



The mechanism of the production of this form of varicosity by portal obstruc- 

 tion will be more readily understood by reference to Fig. 534, which also explains 

 other phenomena associated with that condition. 



The superficial epigastric vein is often visible. Through its anastomosis with 

 the deep and superior epigastric veins it is connected with the portal and parumbilical 

 veins and may be enlarged as a symptom of hepatic disease (page 1727). 



The area ot redness about the umbilicus seen in some forms of peritonitis 

 is probably due to inflammation extending along the obliterated umbilical vein 

 (page 1757). 



The surface veins above the umbilicus empty into the axilla and those below that 

 level into the groin, but the venous currents may be reversed by disease. . For 

 example, the superficial epigastric and superficial circumflex iliac normally empty 

 into the internal saphenous vein a little below Poupart's ligament. In cases of 

 obstruction of the inferior vena cava the blood-current is reversed (as it is in the 

 corresponding deep veins), they enlarge, and, by anastomosing with the superior 

 epigastric, internal mammary, and thoraco-epigastric veins, carry blood from the 

 lower limbs into the axillary or innominate, and so into the superior vena cava. 



In hepatic obstruction, although the superficial epigastric may become varicose 

 (through its connection with the parumbilical and portal veins), this reversal of the 



blood-current does not occur 

 Fig. 534. in it, as may be shown by 



emptying the vein by press- 

 ure and observing the di- 

 rection of the current as it 

 refills. 



The superficial lymphatics 

 of the abdominal wall below 

 the umbilical level empty into 

 the nodes at the groin, those 

 above that level into the 

 nodes in the axilla. 



6. The nerves of the 

 abdominal wall (page 535) 

 have already been described 

 in their relation to various 

 clinical phenomena (pages 

 1683,1755). In addiiion, it 

 shftuld be said here that the 

 definiteness of the relation 

 in nerve-supply between cu- 

 taneous areas and abdominal organs is often of great value in diagnosis. As the 

 sixth to the twelfth thoracic and the first lumbar spinal segments aid in the nerve- 

 supply to the abdominal viscera, and as the corresponding spinal nerves supply the 

 skin of the abdomen, pain due to visceral disease is often referred (through the com- 

 municating branches with the splanchnic and the sympathetic visceral nerves) to the 

 peripheral terminations on the skin of the abdomen, which may even be sensitive to 

 the touch. 



It is possible to map out approximately on the surface the area of distribution 

 of the cutaneous branches from each of these segments (Fig. 535). 



Head has associated as follows these areas (which are almost identical with the 

 areas of distribution of the corresponding spinal nerves) and the viscera in closest 

 connection with them : 



The sixth, seventh, eighth, and ninth thoracic segments with the stomach ; the 

 ninth, tenth, eleventh, and twelfth thoracic segments with the intestinal tract ; the 

 seventh, eighth, ninth, and tenth thoracic segments with the liver and gall-bladder ; 

 the tenth, eleventh, and twelfth thoracic and the first lumbar segment with the kid- 

 ney and ureter ; the second, third, and fourth sacral with the rectum. 



Hemorrhoid* 



CAPUT 

 MeOUSAC 



Diagram showing anatomical relations of certain clinical phenomena in 

 cirrhosis of liver. [After Hare and Taylor.) 



