

THE VAGUS NERVE 



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arch of the aorta, and descends behind the root of the left lung, forming there 

 the posterior pulmonary plexus. From this it runs along the anterior surface of the 

 esophagus, where it unites with the nerve of the right side in the esophageal 

 plexus, and is continued to the stomach, distributing branches over its antero- 

 superior surface; some of these extend over the fundus, and others along the lesser 

 curvature. Filaments from these branches enter .the lesser omentum, and join the 

 hepatic plexus. 



The Jugular Ganglion (ganglion jugulare; ganglion of the root) is of a grayish 

 color, spherical in form, about 4 mm. in diameter. 



Branches of Communication. This ganglion is connected by several delicate 

 filaments to the cranial portion of the accessory nerve; it also communicates by 

 a twig with the petrous ganglion of the glossopharyngeal, with the facial nerve 

 by means of its auricular branch, and with the sympathetic by means of an ascend- 

 ing filament from the superior cervical ganglion. 



The Ganglion Nodosum (ganglion of the trunk; inferior ganglion) is cylindrical 

 in form, of a reddish color, and 2.5 cm. in length. Passing through it is the cranial 

 portion of the accessory nerve, which blends with the vagus below the ganglion. 



Branches of Communication. This ganglion is connected with the hypoglossal, 

 the superior cervical ganglion of the sympathetic, and the loop between the first 

 and second cervical nerves. 



Branches of Distribution. The branches of distribution of the vagus are: 



In the Jugular Fossa . 



In the Neck 



In the Thorax .... 

 In the Abdomen . 



Meningeal. 

 Auricular. 

 : Pharyngeal. 

 Superior laryngeal. 

 Recurrent. 

 Superior cardiac. 

 Inferior cardiac. 

 Anterior bronchial. 

 Posterior bronchial. 

 .Esophageal. 

 Gastric. 

 Celiac. 

 Hepatic. 





The Meningeal Branch (ramus meningeus; dural branch) is a recurrent filament 

 given off from the jugular ganglion; it is distributed to the dura mater in the 

 posterior fossa of the base of the skull. 



The Auricular Branch (ramus auricularis; nerve of Arnold) arises from the jugular 

 ganglion, and is joined soon after its origin by a filament from the petrous ganglion 

 of the glossopharyngeal; it passes behind the internal jugular vein, and enters the 

 mastoid canaliculus on the lateral wall of the jugular fossa. Traversing the sub- 

 stance of the temporal bone, it crosses the facial canal about 4 mm. above the stylo- 

 mastoid foramen, and here it gives off an ascending branch which joins the facial 

 nerve. The nerve reaches the surface by passing through the tympanomastoid 

 fissure between the mastoid process and the tympanic part of the temporal bone, 

 and divides into two branches: one joins the posterior auricular nerve, the other 

 is distributed to the skin of the back of the auricula and to the posterior part of 

 the external acoustic meatus. 



The Pharyngeal Branch (ramus pharyngeus), the principal motor nerve of the 

 pharynx, arises from the upper part of the ganglion nodosum, and consists prin- 

 cipally of filaments from the cranial portion of the accessory nerve. It passes 

 across the internal carotid artery to the upper border of the Constrictor pharyngis 



