APPLIED ANATOMY. 



superior thyroid or the ascending pharyngeal may either one be the first given off 

 by the external carotid, or may come off from the common carotid itself just before its 

 bifurcation. 



The superior thyroid artery is given off in the interval between the hyoid 

 bone and upper border of the thyroid cartilage. It gives a small infrahyoid branch 

 to the thyrohyoid membrane, also a superior laryngeal branch to the inside of the 

 larynx. This branch pierces the thyrohyoid membrane in company with the superior 

 laryngeal nerve to reach the interior of the larynx. The sternomastoid branch, to 

 the muscle of that name, comes off at this point and crosses the common carotid artery. 

 It is of some importance on this account because in ligating the common carotid 

 artery above the omohyoid muscle it is likely to be cut and cause bleeding. Another 

 branch of the superior thyroid artery is the cricothyroid. It is small, rests on the 

 cricothyroid membrane, and is the first artery liable to be cut in an incision down the 



Digastric 

 Mylohyoi 



Sublingual gland 

 Geniohyoid 



Submaxillary duct 

 Submaxillary gland 

 Hypoglossal nerve^ \ |f*""' ff jffcyif'y ^ ^ -~ Lingual nerve 



Superior constrictor 

 Styloglossus 

 Parotid gland 

 Hyoglossus 

 Middle constrictor 

 Stylohyoid tendon 

 Digastric tendon 



Thyrohyoid 



Inferior constrictor 

 Omohyoid 

 Sternothyroid 

 Sternohyoid 



FIG. 1 66. Submaxillary region mylohyoid muscle cut away showing the sublingual gland and anterior portion 



of Submaxillary gland. 



median line. Bleeding from it is not apt to be serious. The remainder of the 

 superior thyroid artery supplies the thyroid gland. 



The ascending pharyngeal is a long slender branch that comes from the 

 under side of the main trunk. It lies on the superior and middle constrictors of the 

 pharynx and goes clear to the skull, giving off some meningeal branches. In ligat- 

 ing the external carotid care should be taken not to include this vessel in the ligature. 

 It also gives branches to the soft palate, tonsil, recti capitis antici muscles, and 

 tympanum. 



The lingual is given off just below the greater horn of the hyoid bone, and 

 passes forward beneath the hyoglossus muscle to supply the tongue and sublingual 

 tissues. The hypoglossal nerve lies above the artery and on the hyoglossus muscle. 



The facial comes off just above the lingual artery or often in a common trunk 

 with it. It passes upward and forward in a groove in the under surface of the sub- 

 maxillary gland and passes over the edge of the jaw at the anterior border of the 

 masseter muscle. The facial vein at this point is posterior to it. 



The occipital artery comes off almost opposite the facial. It passes upward 

 and backward between the mastoid process and the transverse process of the atlas, 



