SPHENO-PALATINE GANGLION 403 



palate bone, and a portion of the body of the sphenoid, with the bone 

 forceps, it may be more or less satisfactorily exposed. In the same 

 restricted space will be found the terminal portion of the internal maxillary 

 artery, from which numerous branches are given off. 



Ganglion Spheno-palatinum. This is a small, triangular 

 flattened body, which is lodged in the pterygo- palatine fossa. 

 It is embedded in soft fat, and is surrounded by the ter- 

 minal branches of the internal maxillary artery. Two stout 

 spheno - palatine branches descend from the maxillary nerve 

 and join it from above, but only certain of their fibres 

 are involved in the ganglion ; the remainder are continued 

 directly into the nasal and palatine nerves which proceed 

 from the ganglion. The spheno-palatine branches may be 

 regarded as constituting the sensory roots of the ganglion. 



From the spheno-palatine ganglion branches are given off 

 which radiate in four directions viz., medially to the nose ; 

 downwards to the palate ; posteriorly to establish connections 

 with the facial nerve and carotid plexus, as well as to supply 

 the mucous membrane of the pharynx ; and anteriorly to the 

 orbit. 



Medial branches, . Posterior superior nasal nerves. 

 Anterior palatine. 



Descending branches, 



Posterior branches, 

 Anterior branches, 



Middle palatine. 



Posterior palatine. 



Nerve of pterygoid canal. 



Some lateral posterior superior nasal 



branches. 



Orbital. 



From the internal maxillary artery twigs are given off 

 which accompany these nerves. 



Posterior Superior Nasal Nerves. There are two groups of 

 the posterior superior nasal nerves, a medial and a lateral. 

 The medial branches pass through the spheno-palatine 

 foramen and across the roof of the nasal cavity to the posterior 

 part of the septum. The largest of them, the naso-palatine 

 nerve, runs downwards and anteriorly in a groove on the 

 surface of the vomer (p. 392). Some of the branches of the 

 lateral posterior group also pass through the spheno-palatine 

 foramen and are distributed to the superior meatus, to the 

 superior and middle conchae, and to the posterior ethmoidal 

 air cells. Other branches of the lateral group pass posteriorly, 

 some in the muco-periosteum of the upper and posterior part 

 of the nasal cavity, and one in the pharyngeal canal (O.T. 



ii 26 a 



