THE PORTAL SYSTEM OF VEINS. 



991 



As it crosses the umbilical fossa, the left branch of the portal vein is joined, 

 anteriorly, by the round ligament of the liver and some small veins, and, posteriorly, 

 by the ligamentum venosum. The round ligament is a fibrous cord which passes 

 from the umbilicus to the left branch of the portal vein. It represents the 

 remains of the left umbilical vein of the foetus. The small veins which accompany 

 it connect the left branch of the portal vein with the superficial veins round the 

 umbilicus. The ligament venosum connects the left branch of the portal vein 

 with the upper part of the inferior vena cava. It is the remains of a foetal blood- 



Lig. venosum 



Vena cava inferior - 

 V. hepatis dextra 

 (systemic and portal blood) 



Liver capillaries - 



V. porta (ramus dextra) 



V. cystica 



V porta 



V. pancreatico duodenal 

 V. mesenterica _ 



superior 

 V. colica media 



V. colica dextra 



V. hepatis sinistra (systemic and portal blood) 

 V. porta (ramus sinister) 

 Liver capillaries 



Vv. oesophageae 



V.coronaria 

 - ~ ventriculi 



gastricse breves 



v. lienales 



V. gastroepi- 

 1 ploica sinistra . 

 V. lienalis 

 V. gastroepiploica dextra 



- -V. mesenteric inferior 



V. colica sinistra 



_Lig. teres hepatis cum 

 vv. umbilicales 



V. liypogastrica dextra ~ 

 V. iliaca externn 



V. htemorrhoidalis media" 



V. hffimorrhoidalis inferior dextra__ 



Umbilicus 

 -Vv. jejunales 



V. sigmoidea 

 V, iliaca communis 

 - .V. hsemorrhoidalis superior 



<V hypogastrica sinistra 



"V.-Hiaca externa 



Vr- ksemorrhoidalis media 



V. hsemorrhoidalis inferior sinistra 



FIG. 796. SCHEMA OF THE PORTAL SYSTEM OF VEINS AND ITS CONNECTIONS WITH THE SYSTEMIC 

 SYSTEM. It must be remembered that systemic blood carried by the hepatic artery also enters the 

 liver capillaries, therefore the hepatic veins contain both portal and systemic blood. 



vessel, the ductus venosus, through which blood, carried from the placenta by the 

 left umbilical vein, passed to the inferior vena cava without going through the liver. 

 The portal vein is accompanied by numerous lymph vessels, and it is surrounded, 

 in the lesser omentum, by filaments of the hepatic plexus of nerves. 



Tributaries. Soon after its formation the portal vein receives the coronary and 

 right gastric veins, and the cystic vein opens into its right branch. 



Vena Coronaria Ventriculi. The coronary vein commences in the lesser omentum 

 by the union of tributaries from both surfaces of the stomach. It runs to the left 



