LYMPHADENITIS. 285 



in that of the eyelids, inflammation leads to very rapid infiltration 

 and very great swelling of the part. 



Injuries to lymphatic trunks. The thoracic duct rises well 

 into the neck on the left side, arching over the apex of the pleural 

 sac and the first part of the left subclavian artery. It is here 

 exposed to injury most frequently from operative procedures at 

 the lower part of the left posterior triangle of the neck. In a 

 fair proportion of cases the duct enters by more than one terminal 

 vessel into the junction of the left internal jugular and left 

 subclavian veins, and it is possible, therefore, for a wound to 

 involve only one division and thus cause but little trouble. In 

 the thorax the duct lies along the front of the bodies of the lower 

 seven thoracic vertebrae and then passes to the left side of the 

 upper five bodies. Here it has numerous communications with 

 the azygos veins, which is another reason why injury to the 

 main trunk in the neck is sometimes followed by a minimum of 

 inconvenience. Fracture of one or more thoracic vertebrae may 

 lead to damage to the duct. Injury to the receptaculum chyli, 

 as it lies upon the front of first and second lumbar vertebrae, 

 may occur during operations at this level of the abdomen, or 

 from gunshot-wounds. 



LYMPHATIC GLANDS. 



All lymphatic vessels either pass to or proceed from lymphatic 

 glands. These structures, therefore, filter lymph received by the 

 afferent vessels and transmit it afterwards through the efferent 

 vessels to the vascular system. Hence the great liability for 

 lymphatic nodes to suffer from the entrance and arrest of 

 improper substances circulating in the lymph stream. 



Lymphadenitis The Upper Extremity. The fingers and 

 hand are provided with a very intricate and delicate reticulum 

 of lymphatic capillaries, so that even a pin prick must neces- 

 sarily open up many lymphatic spaces. Infection, therefore, of 

 the superficial lymphatics is very common, and resulting lympha- 

 denitis is extremely frequent. The lymph is conveyed from 

 the palm and dorsum of the hand by vessels which correspond 



