THE LYMPH NODES OF THE HEAD AND FACE 777 



subclavian trunk; from the right side of the thorax, the right lung, and right side 

 of the heart, and from part of the convex surface of the liver, through the right 

 bronchomediastinal trunk. These three collecting trunks frequently open sepa- 

 rately in the angle of union of the two veins. 



Applied Anatomy. Blockage of the thoracic duct by mature specimens of the minute 

 parasitic worm Microfilaria nocturna gives rise to stasis of the chyle, and to its passage in various 

 abnormal directions on its course past the obstruction. The neighboring abdominal, renal, 

 and pelvic lymphatics become enlarged, varicose, and tortuous, and chyle may make its way 

 into the urine (chyluria), the tunica vaginalis (chylocele), the abdominal cavity (chylous ascites], 

 or the pleura! cavity (chylous pleural effusion), in consequence of rupture of some of these 

 distended lymphatic vessels. 



The thoracic duct may be secondarily infected in intestinal or pulmonary tuberculosis, and 

 may contain either miliary tubercles, caseating tuberculous masses, or even tuberculous ulcers. 

 It is often the seat of secondary carcinomatous deposits in cases of cancer of some abdominal 

 viscus, becoming infiltrated throughout until it becomes a stiff moniliform rod as thick as a 

 pencil, with multiple stenoses and dilatations of its lumen; in such cases the left supraclavicular 

 nodes often become infected and enlarged, while the lungs remain entirely free from secondary 

 growths. 



LYMPHATICS OF THE HEAD, FACE, AND NECK. 



Intracranial lymphatics have not been demonstrated. It is probable, but not 

 yet conclusively demonstrated, that the perivascular spaces around the cerebral 

 arteries are the beginning of a cerebral lymph system, and that these perivascular 

 lymph channels pass out of the cranium with the arteries and the internal jugular 

 veins and terminate in the superior deep cervical nodes. It is also probable 

 that lymph spaces surround the dural bloodvessels and terminate in the superior 

 deep cervical and the internal maxillary nodes. The lymphatics of the nasal 

 fossae can be injected from the subdural and subarachnoid spaces. 



The extracranial lymphatics are divided into superficial and deep, and the two 

 systems freely communicate. All of these vessels run into nodes about the 

 head and neck. The superficial lymphatics take origin in the subcutaneous 

 tissue and superficial muscles. The deep vessels arise in the orbit, mouth, nose, 

 pharynx, oesophagus, tongue, larynx, and the muscular, ligamentous, and osseous 

 structures. 



The Lymph Nodes of the Head and Face. 



The lymphatic nodes of the head and face are as follows: 



1. The Occipital. 



2. The Posterior Auricular. 



3. The Parotid and Subparotid. 



4. The Facial. 



5. The Internal Maxillary. 



6. The Lingual. 



7. The Retropharyngeal. 



The occipital nodes (lymphoglandulae occipitales] (Fig. 556), one to three 

 in number, are situated upon the occipital insertion of the Complexus muscle, 

 at the lateral border of the Trapezius, and beneath the deep fascia. Their 

 afferents drain the occipital region of the scalp, while their efferents pass to the 

 upper deep cervical nodes. 



The posterior auricular or mastoid nodes (lymphoglandulae auricidares 

 posteriores (Fig. 556), usually two in number, are situated upon the mastoid 

 insertion of the Sternomastoid muscle. Their afferents drain the posterior part 

 of the temporoparietal region, the upper part of the internal surface of the pinna, 



