THE MOUTH AND THROAT. 115 



median line, and on breaking may cause suffocation by passage of the pus into the 

 larynx. If, as is usually the case, the pus involves the tissue around the tonsil, form- 

 ing a peritonsillar abscess, it pushes upward behind the anterior pillar into the supra- 

 tonsillar fossa and bulges forward, stretching the pillar over it. To evacuate this pus 

 an incision should be made directly anteroposteriorly, with the flat side of the blade 

 parallel with the edge of the pillar, or a slender pair of haemostatic forceps may be used. 

 A centimetre and a quarter ( ^ in. ) is deep enough usually to plunge the knife ; the 

 point should not be pointed outwardly but directly backward. The incision should 

 be just above the upper and lateral edge of the anterior pillar (Fig. 143). Some 

 small vessels may bleed, but this will either stop spontaneously or may be controlled 

 by packing. The ascending pharyngeal artery lies beneath the tonsil. The tonsil 

 lies on the pharyngeal aponeurosis and the superior constrictor muscle, while the as- 



Anterior pillar 



Styloglossus 

 Stylopharyngeus 



Stylohyoid 



Internal carotid artery 



Internal jugular vein 



Digastric 



Sternomastoid 



Longus colli 



Rectus capitis anticus major 



FIG. 144. Transverse frozen section passing through the faucial tonsil and showing its relation to the internal 



carotid artery. 



cending pharyngeal artery and external carotid lie outside of them, so that both 

 structures would have to be cut before the vessels would be wounded. The internal 

 carotid artery lies still deeper (2 to 2.5 cm.) behind and external to the tonsil. It is 

 usually well out of harm's way unless dilated (see page 123, Fig. 156), but the pus may 

 burrow into it and cause fatal hemorrhage. Sometimes pus may burrow through the 

 constrictor muscle and enter the tissues of the neck. In severe tonsillitis the deep 

 lymphatics beneath the angle of the jaw become enlarged. 



Hypertrophy of the tonsils is common and is treated by removing them entirely or 

 level with the palatal arches. An instrument called the tonsillotome is used, or it 

 is done with a knife or scissors or ^nare. Fatal bleeding has followed this oper- 

 ation. The blood supply to the tonsil has already been given. If the bleeding is so 

 free as to threaten the life of a patient, the external carotid artery should be ligated 

 as all the vessels supplying the tonsil are derived from it. 



