THE LYMPHATICS OF THE THORAX 801 



The lymphatic vessels of the vagina are carried in three directions those, of 

 the upper part to the external iliac nodes, /'hose of the middle part to the internal 

 iliac nodes, and those of the lower part to the common iliac nodes. On the 

 course of those from the middle and lower parts small nodes are situated. Some 

 lymphatics from the lower part of the vagina join those of the vulva and pass to 

 the superficial inguinal nodes. The lymphatics of the vagina anastomose with 

 those of the cervix uteri, vulva, and rectum, but not with those of the bladder. 



THE LYMPHATICS OF THE THORAX. 



The lymph nodes of the thorax may be divided into parietal and visceral the 

 former being situated in the thoracic wall, the latter in relation to the viscera. 



The parietal lymph nodes include the internal mammary, intercostal, and 

 diaphragmatic nodes. 



1. The internal mammary nodes are placed at the anterior extremities of the 

 intercostal spaces, by the side of the internal mammary artery. They derive 

 .afferents from the mammary gland, from the deeper structures of the anterior 

 abdominal wall above the level of the umbilicus, from the upper surface of the 

 liver through a small group of nodes which lie behind the ensiform cartilage, 

 and from the deeper parts of the anterior portion of the thoracic wall. Their 

 eft'erents usually unite to form a single trunk on either side; this may open directly 

 into the junction of the internal jugular and subclavian veins, or that of the right 

 side may join the right subclavian trunk and that of the left the thoracic duct. 



2. The intercostal nodes (lymphoglandulae intercostales) occupy the posterior 

 parts of the intercostal spaces, in relation to the intercostal vessels. They receive 

 the deep lymphatics from the postero-lateral aspect of the thorax; some of these 

 vessels are interrupted by small lateral intercostal nodes. The efferents of the 

 nodes in the lower four or five spaces unite to form a trunk, which descends and 

 opens either into the receptaculum chyli or into the commencement of the thoracic 

 duct. The efferents of the nodes in the upper spaces of the left side terminate 

 in the thoracic duct; those of the corresponding right spaces, in the right lymphatic 

 duct. 



3. The diaphragmatic nodes lie on the thoracic aspect of the Diaphragm, and 

 consist of three sets anterior, middle, and posterior. 



The anterior set consists of (a) two or three small nodes behind the base of 

 the ensiform (xiphisternum), which receive afferents from the convex surface 

 of the liver, and (6) one or two nodes on either side near the junction of the seventh 

 rib with its cartilage, which receive lymphatic vessels from the front part of the 

 Diaphragm. The efferent vessels of the anterior set pass to the chain of internal 

 mammary nodes. 



The middle set consists of two or three nodes on either side close to where the 

 phrenic nerves enter the Diaphragm. On the right side some of the nodes 

 o ( this group lie within the fibrous sac of the pericardium, in front of the inferior 

 vena cava. The afferents of this set are derived from the middle part of the 

 Diaphragm, those on the right side also receiving afferents from the convex 

 surface of the liver. Their efferents pass to the posterior mediastinal nodes. 



The posterior set consists of a few nodes situated on the back of the diaphrag- 

 matic crura, and connected on the one hand with the lumbar nodes and on the 

 other with the posterior mediastinal nodes. 



The superficial lymphatic vessels of the thoracic wall ramify beneath the 

 skin and converge to the axillary nodes. Those over the Trapezius and Latis- 

 simus dorsi run forward and unite to form ten or twelve trunks which end in the 



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