BRANCHES OF UPPER CERVICAL GANGLION. 3G3 



communicates with the third, the fourth, and the ophthalmic division of the fifth 

 cranial nerves. 



BRANCHES. (a) The filament which joins the third nerve comes into connection 

 with it close to the point of division of that nerve. 



(&) The branch to the fourth nerve, which may be derived from either the 

 cavernous or the carotid plexus, joins the nerve where it lies in the wall of 

 the cavernous sinus. 



(c) The filaments connected with the ophthalmic trunk of the fifth nerve are 

 supplied to its inner surface. 



(d) The sympathetic root of the ciliary ganglion passes from the cavernous 

 plexus into the orbit, either separately, or in connection with the nasal nerve, or, 

 according- to Reichart, with the third nerve (p. 238). 



(e) Minute filaments are furnished to the pituitary body. 



2. PHARYNGEAL NERVES AND PLEXUS. These nerves arise from the fore part of 

 the ganglion, and are directed obliquely inwards to the side of the pharynx. 

 Opposite the middle constrictor muscle they unite with branches of the pneumo- 

 gastric and glosso-pharyngeal nerves ; and by their union with these nerves the 

 pharyngeal plexus is formed. Branches emanating from the plexus are distributed 

 to the muscles and mucous membrane of the pharynx (p. 265). One or two 

 filaments pass from these branches to the superior and external laryngeal nerves 

 (fig. 228). 



3. UPPER CARDIAC NERVE. Each of the cervical ganglia of the sympathetic 

 usually furnishes a cardiac branch, the three being named respectively the upper, 

 middle, and lower cardiac nerves. 



These branches are continued singly, or in connection, to the large prevertebral 

 centre (cardiac plexus) of the thorax. Their size varies considerably, and where 

 one branch is smaller than common, another will be found to be increased in size, 

 as if to compensate for the defect. There are some differences in the disposition of 

 the nerves of the right and left sides. 



The upper or superficial cardiac nerve of the right side proceeds generally 

 from two or more branches of the ganglion, with, in some instances, an offset from 

 the cord connecting the first two ganglia. In its course down the neck the nerve 

 lies in the back of the carotid sheath, along the front of the longus colli muscle ; it 

 crosses either in front of or, less frequently, behind the inferior thyroid artery, and is 

 placed in front of the recurrent laryngeal nerve. Entering the thorax, it passes in 

 some cases before, in others behind, the subclavian artery, and is directed along the 

 innominate artery to the back part of the arch of the aorta, where it ends in 

 the deep cardiac plexus, a few small filaments continuing also to the front of 

 the great vessel. Some branches accompany the inferior thyroid artery to be 

 distributed to the thyroid body. 



In its course downwards this cardiac nerve is repeatedly connected with other 

 branches of the sympathetic, and with the pneumo-gastric nerve. Thus, about the 

 middle of the neck it is joined by one or more filaments from the external laryngeal 

 nerve ; and, rather lower down, by one or two filaments from the trunk of the 

 pneumo-gastric nerve (upper cervical cardiac branches) ; lastly, on entering the 

 chest, it joins with the recurrent laryngeal. 



The upper cardiac nerve of the left side has, while in the neck, the same 

 course and relations as that of the right side. Within the chest it follows the left 

 carotid artery to the arch of the aorta, and usually crosses over that vessel to enter 

 the superficial cardiac plexus. In some cases, however, this nerve ends, either 

 wholly or in part, in the deep cardiac plexus, and it then descends behind the arch 

 of the aorta. 



