THE NECK 147 



mouth. They may become infected secondarily from chronic 

 tuberculous disease of the superficial glands, but they are 

 primarily and constantly involved in malignant i disease of 

 the areas which they drain. The efferents from both groups 

 terminate in the upper anterior group of the deep cervical 

 glands (p. 132). 



Good exposure of the region is obtained by a large curved 

 incision similar to that already described for ligature of the 

 second part of the lingual artery (p. 145). This incision is useful 

 when a cold abscess points beneath the skin, because the vitality 

 of the skin immediately over the abscess is not interfered with 

 when the flap is turned up. If a sinus is present, the incision 

 may be made straighter so as to excise it entirely. The skin 

 and platysma are undercut to afford good exposure and to permit 

 the edges to be brought together subsequently. As soon as 

 the deep fascia is cut through, the anterior facial vein is exposed, 

 running downwards and backwards on the surface of the sub- 

 maxillary salivary gland, but it may be displaced or it may be 

 embedded amongst the enlarged lymph glands. It enters the 

 region by piercing the deep fascia at the anterior border of the 

 masseter muscle, just behind the external maxillary (facial) 

 artery, and leaves it, as the common facial vein, by passing 

 superficial to the posterior belly of the digastric. If it is cut, 

 both ends must be ligatured, as they may give rise to severe 

 haemorrhage, especially when the vessel is injured near its 

 junction with the internal jugular vein (p. 118). After the an- 

 terior facial vein has been dealt with, the superficial lymph 

 glands may be removed, but they must be distinguished from 

 the lobules of the salivary gland, which closely resemble them 

 in appearance. 



The removal of the deep lymph glands is complicated by their 

 relation to the external maxillary (facial) artery. Normally, 

 the vessel runs first upwards and then forwards and downwards 

 in a well-marked groove on the deep surface of the salivary 

 gland, but it may be displaced or surrounded by the lymph glands 

 when they are enlarged. The salivary gland is turned upwards 

 and the position of the artery is ascertained, but the vessel is 

 liable to be wounded as it crosses the inferior border of the 

 mandible (p. 174). Thereafter the enlarged lymph glands can 

 be safely taken away. If the glands are malignant, the whole 

 group (i.e. both superficial and deep), together with the salivary 

 gland and the portion of the external maxillary (facial) artery 



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