Arteries of the Head. 



397 



V. ophtlialmica superior 



Ramus pctrosus superficialis 

 A. tyiiipanica 

 superior (from the 

 a. meningeamcdia) 



Sinus eavcruosus 



A. tyiiJpanica 

 posterior(from~ " 

 the a. slylo- 

 mastoidea) 



Rami _- 

 mastoidei 



Cellulae 

 mastoideae 



A. stylomastoidea 



^:^x 



- - Plexus venosus 

 caroticus intemus 



Ramus 

 caroticotympanicus 

 -A. tympanica inferior(from 

 the a. pharyngea ascendens) 



Fossa jugularis 

 M. longus capitis 

 A. tympanica inferior 



A. carotis interna 



A. pharyngea ascendens 



Atlas 



442. A. carotis interna and the middle ear, viewed from the right. 



(The temporal b(jne has been cut open and drawn as in Fig. 1 1 ; the plexus venosus caroticus 

 internus has been introduced after N. Kiidinger. Magnification : 3:2.) 



A. carotis interna (internal carotid artenj) {?,ee a\9,oY\<<:,^ am, i\\, Ai'i im^\.A.A.^), 

 curved slightly like the letter S, runs in front of the mm. longus colli and longus capitis to the 

 base of the skull, bounded medianward by the lateral wall of the pharynx; lateralward and be- 

 hind, it adjoins the v. jugularis interna ; in front and lateralward it adjoins below the a. carotis 

 externa, above the glandula parotis and the mm. styloglossus and stylopharyngeus ; the latter 

 muscles separate it Irom the a. carotis externa. It then enters the canalis caroticus, and passes 

 through it going first upward , then horizontally medianward and forward , rims through the 

 foramen lacerum in a groove of the fibrocartilago basalis, turns upward and goes, slightly curved, 

 in the sulcus caroticus of the body of the sphenoid bone to a position below the processus 

 clinoideus anterior; there it bends sharply backward and upward, medial from the proc. clinoideus 

 anterior and behind the foramen opticum , perforates the dura mater and breaks up into its 

 terminal branches lateral from the chiasma opticuru, below the substantia perforata anterior. Inside 

 the canalis caroticus it is surrounded by the plexus venosus caroticus internus, in the sulcus 

 caroticus by the sinus cavernosus (see also Fig. 482). In tlie neck it gives off" no branches, 

 in the canalis caroticus it gives off the ramus caroticotympanicus , in the sinus cavernosus 

 small branches to the surrounding parts and during its course behind the foramen opticum, 

 from the convexity of its last curve, the a. ophthalmica. 



1. Ramus caroticotympanicns (0. T. tympanic branch), a fine branch which passes 

 through one of the canaliculi caroticotympanici to the mucous membrane of the middle ear. 



2. A. ophthalmica (see Fig. 443), at the lateral inferior surface of then, opticus, goes 

 through the foramen opticum into the orbit, then bends somewhat upward and passes trans- 

 versely over the n. opticus, between it and the m. rectus superior, to the junction of the medial 

 with the upper wall of the orbit; there it passes, below the m. obliquus superior, forward and 

 divides between the trochlea and the ligamentum palpebrale mediale into its terminal branches : 

 aa. palpebrales mediales, dorsalis nasi and frontalis. Branches: 



Spalteholz, Atlas. 26 



