THE LYMPH VESSELS OF HEAD AND NECK. 1003 



and the levator scapulae and the scalene muscles, and several of them are in close 

 relation with the accessory, nerve (Fig. 801). 



The superior deep cervical glands are connected by afferent vessels with the 

 various groups of glands which lie in the regions of the pharynx, the face, and the 

 upper part of the neck. They receive lymph, therefore, from the nose, the mouth, 

 the tongue, the upper parts of the pharynx and .larynx, the tonsil, the upper part 

 of the thyreoid gland, the submaxillary, sublingual, and parotid salivary glands, and 

 from the .interior of the cranium. Their efferents pass either to the inferior deep 

 cervical glands or to the jugular lymph trunk. In some cases the medial and 

 lateral members of the superior group are connected with the corresponding 

 members of the lower group only, but in other cases the medial or lateral 

 members of the superior group may be connected with both the medial and the 

 lateral members of the inferior glands. 



The inferior deep cervical lymph glands (Figs. 800, 801), which are also termed 

 the supra-clavicular glands, are situated below the level of the omo-hyoid muscle. 

 (1) The members of the medial group lie in relation with the lower part of the 

 internal jugular vein, opposite the interval between the sternal and the clavicular 

 heads of the sterno-mastoid. They receive afferents from the members of the 

 upper medial group and from the pretracheal and the paratraeheal glands and from 

 the upper part of the thorax. Their efferents unite with some of the efferents of the 

 upper medial group and pass with them to the jugular lymph trunk. 



(2) The members of the lateral group of inferior deep cervical glands lie in 

 the subclavian triangle, in the fatty tissue superficial to the lower part of the 

 brachial plexus and the third part of the subclavian artery. They receive lymph 

 from the lower parts of the neck, from the upper part of the thorax, and from 

 the upper lateral glands. They receive lymph also from the deep parts of the 

 mammary gland, and they are in communication with the axillary glands. Their 

 efferents join the jugular lymphatic trunk. 



THE LYMPH VESSELS OF THE HEAD AND NECK. 



The lymph vessels of the head and neck may be separated into two groups, intracranial and 

 extracranial. 



Intracranial Lymph Vessels and Lymph Spaces. The cerebro-spinal fluid which fills the 

 ventricles of the brain, the central canal of the spinal medulla, and the subarachnoid and 

 subdural spaces, differs in chemical constitution from true lymph; nevertheless it plays the 

 part of lymph, to some extent, and there can be little doubt that some of it eventually passes 

 into lymph vessels ; therefore it may be considered as a modified form of lymph. The fluid is 

 secreted by the chorioid plexuses of the cerebral ventricles, and it passes through the medial and 

 lateral foramina of the fourth ventricle into the cerebello - medullary subarachnoid cistern, 

 Part of the fluid transudes through the arachnoideal granulations into the superior sagittal and 

 other cerebral blood sinuses ; and part, probably, passes by osmosis into the subdural space 

 and thence into the meningeal lymphatics, by which it is conveyed to the exterior of the 

 cranium. 



Cerebral Lymph Channels. It appears probable that the so-called peri-vascular and peri- 

 cellular lymph spaces which have so frequently been described in the central nervous system are 

 merely artifacts produced by unsatisfactory methods of preparation. Nevertheless, the fluid 

 which pervades the cerebral substance must have some exit, and it is not unlikely that it passes, 

 with the lymphocytes, through cleft-like intercommunicating spaces in the adventitial coats of 

 the blood vessels, similar to those demonstrated by Bruce in the case of the spinal medulla, and 

 so reaches the pia-mater and subarachnoid space ; that is, it runs along the walls of the arteries, 

 enters the meningeal lymphatics, and passes through them to the exterior of the cranium and 

 where it enters the extracranial lymph vessels. The above statements are based upon Bruce's 

 researches and the fact that the lymph vessels of the nose, the ear, and the deep lymph vessels 

 of the neck have been injected from the subdural space. 



The Superficial Lymph Vessels of the Head. (1) The superficial lymphatics from the 

 frontal and anterior temporal regions of the head accompany the branches of the superficial 

 temporal artery and terminate in anterior auricular glands, from which efferents pass to the 

 parotid, the superficial cervical, and to the medial glands of the superior deep cervical group. 



(2) The lymphatics of the posterior temporal and parietal region run to the posterior auricular 

 glands. It is stated that they sometimes communicate directly with the lateral glands of the 

 superior deep cervical group. 



(3) The lymphatics from the occipital part of the scalp pass along the branches of the occipital 

 artery and terminate in the occipital glands, which transmit the lymph to the lateral superior 

 deep cervical glands. 



