96o HUMAN ANATOMY. 



Swellings of this deep chain of glands — especially of those beneath the sterno- 

 mastoid — may be present without being distinctly palpable, and are apt, in any case 

 severe enough to come to operation, to involve many more nodes than were 

 previously suspected. 



One node of the upper group lies behind the posterior belly of the digastric in 

 the angle between the internal jugular and facial veins. Leaf has suggested that 

 it be called the " jugulo-digastric" node. In some affections of the tonsil and of 

 the base of the tongue, it enlarges and projects in front of the anterior border of the 

 sterno-mastoid, its contents being about half an inch below and somewhat internal to 

 the angle of the jaw. 



Other glands of this group, which are very constant in position, lie over the 

 insertion of the splenius capitis under cover of the upper end of the sterno-mastoid 

 and surround the spinal accessory nerve before it perforates the latter muscle. En- 

 largement of these glands would compress the nerve against the transverse process 

 of the atlas (Leaf). 



The retropharyngeal nodes lie in the space of. that name (page 552), about 

 opposite the axis, on the rectus capitis anticus major and to the inner side of the 

 glosso-pharyngeal nerve where it curves around the lower border of the stylo- 

 pharyngeus. They communicate with the upper gi:oup of the deep nodes. They 

 may be enlarged from infection through the overlying mucosa, as they are in close 

 relation to the buccal portion of the pharynx, which, on account of its many crypts 

 or recesses, the large amount of adenoid tissue present, its relatively direct exposure 

 to mechanical injury and to the current of inspired air (drying it, reducing its 

 temperature, and possibly conveying microbic irritants), is especially susceptible to 

 inflammation. They may also enlarge as a result of caries of the bodies of the 

 cervical vertebrae. In either case, there may be pharyngeal and tonsillar pain, ear- 

 ache, and other evidence of glosso-pharyngeal irritation. If suppuration occurs, a 

 fluctuating swelling appears which pushes the posterior wall of the pharynx forward 

 (the retropharyngeal connective tissue being lax to permit of the free movement of 

 the pharynx during deglutition), depresses the soft palate, and causes dysphagia ; 

 or, if lower, pauses dysphonia and dyspnoea by obstructing the laryngeal opening. 

 Such an abscess may gravitate along the oesophagus into the mediastinum and may 

 even reach the diaphragm ; or it may extend laterally behind the parotid and great 

 vessels to the side of the neck, or, reaching the cords of the brachial plexus, may be 

 conducted by them to the posterior cervical triangle or down into the axilla. Such 

 an abscess should not be left to spontaneous evacuation, on account of the danger 

 of its extension in these directions, or — if the abscess should suddenly burst into the 

 pharynx — of suffocation or of septic pneumonia if the pus entered the air-passages. 

 It may be opened through the mouth, in the mid-line of the pharynx (the head 

 being bent over so that the pus would not run toward the glottis), or externally by 

 an incision along the posterior margin of the sterno-mastoid, the great vessels being 

 pushed forward as the wound is deepened. 



The lower group of deep cervical nodes enlarge most frequently consecutively 

 to infection or disease of the upper group. They also receive the lymphatics from 

 the supraspinous fossa which follow the suprascapular artery, and those from the 

 upper part of the deltoid. Those that lie at the very base of the neck, in the sub- 

 clavian triangle, or on the omo-hyoid muscle, are not uncommonly affected in the latter 

 stages of mammary carcinoma (page 2035). They are continuous with the axillary 

 nodes, while those to their inner side — lying on the levator anguli scapulae and 

 scalenus medius just external to the internal jugular vein — are also often involved in 

 the upward extension of cancer. Both sets communicate with the mediastinal nodes. 

 On the left side they are in close proximity to the thoracic duct. The branches of 

 the cervical plexus pass among the nodes of this deep cervical group. 



In cases of chronic inflammation and enlargement of these nodes they will usually 

 be found adherent to the internal jugular vein, which is in close relation to most of 

 them. As the majority of them lie beneath the sterno-cleido-mastoid, that muscle 

 will often have to be divided either partially or completely in operations for their 

 removal. Certain cysts, in most cases congenital, usually subcutaneous but with deep 

 prolongations into the intermuscular spaces, are found in the neck, and are believed 



