MAXILLAEY NEEYE. 



775 



NERVUS MAXILLARIS. 



The Maxillary Nerve. This large nerve courses forwards from its origin in 

 the semihmar ganglion through the middle fossa of the skull, in the dura mater, 

 and in relation to the lower part of the cavernous sinus (Fig. 647, p. 771). It 

 passes through the foramen rotundum, traverses the pterygo-palatine fossa, and 

 enters the orbit as the infra-orbital nerve, through the inferior orbital fissure. In 

 the orbit it occupies successively the infra-orbital groove and canal, and it finally 

 appears on the face through the infra-orbital foramen (Fig. 653). 



The branches and communications of this nerve occur (a) in the cavity of the 

 cranium, (Z>) in the pterygo-palatine fossa, (c) in the infra-orbital canal, and (d) 

 on the face. 



Supra-trochlear branch 

 Supra-orbital branch ^-\ 



Lacrimal gland 



Levator palpebrse %' 

 superioris 



Infra-trochlear nerve 

 Obliquus superior 

 muscle 



Anterior ethmoidal 

 nerve 



superiori 

 Frontal nerve 



Jaso- ciliary nerve 

 Lacrimal nerve 



Bectus lateralis ^^g^ ^MBM V Tr^T" ' '" Troclilear nerve 



Superior orbital 



fissure ^^ ^ -^MW., 



Naso-ciliary nerve 



Ophthalmic division jrfHPlT/ ^^^SS^SS^.- Optic nerve 



of trigeminal 



Maxillary division 



of trigeminal 

 Mandibular division 

 of trigeminal 



Semilunar ganglion - 



In the cavity of the cranium the nerve gives off a minute (n. meningeus medius) 

 middle meningeal (O.T. recurrent nerve) to the dura mater of the middle fossa of 

 the skull. 



In the pterygo-palatine fossa the nerve gives off (1) two short thick spheno- 

 palatine nerves, the sensory roots of the spheno-palatine ganglion. 



(2) Posterior superior alveolar nerves, which may be double, descend through the 

 pterygo-maxillary fissure to the lateral side of the maxilla, and proceed forwards 

 along the alveolar arch, in company with the posterior superior alveolar artery. 

 They supply the gum and the upper molar teeth by branches which perforate the 

 bone to reach the alveoli. The nerves form a fine plexus joined by the middle 

 alveolar nerve before finally reaching the teeth. 



(3) A small zygomatic (O.T. orbital) branch enters the orbital cavity through 

 the inferior orbital fissure, and proceeding along the lateral wall, communicates 



Oculo-motor nerve 



Trochlear nerve 



Trigeminal nerve 

 FIG. 651. THE NERVES OF THE ORBIT FROM ABOVE. 



