481 VEIXS OP THE HEAD AND NECK. 



The anterior occipital or transverse sinus (sinns basilaris) is 

 placed at the fore part of the basilar process of the occipital bone, so as 

 to establish a transverse commimication between the two inferior 

 petrosal sinuses. 



OPHTHALMIC VEIN. 



The ophthalmic vein opens into the cavernous sinus. Its branches 

 are distributed in the different structures contained within the orbit, in 

 company Avith the branches of the ophthalmic artery : some small rami- 

 fications arise from the eyelids, whilst others communicate with the 

 angular branch of the facial vein ; and those which accompany the 

 supraorbital artery have similar connections with the veins upon 

 the forehead. All these branches, together with others arising 

 from the lachrymal gland, from the different muscles, from the eth- 

 moidal cells, "and from the globe of the eye, severally named 



Fig. 308. 



Pig. 308. — SxETcn of the Ophthalmic Vein, and of its Disteibtttion ahd Com- 

 munication WITH OTHER Veins (altered from Hirschfeld and Leveille. A. T.) 

 The orbit is opened from the outer side and the dissection is similar to that for dis- 

 playing the ophthalmic artery (Fig. 253, p. 376) ; o, the optic nerve before it enters the 

 optic foramen ; b, the superior oblique muscle divided a little way behind its pulley ; 

 c, the lachrymal gland lying upon the eyeball ; d, the insertion of the inferior oblique 

 muscle ; c, foramen rotundum ; /, sinus maxillaris, opened externally : I, the ophthalmic 

 vein joining the cavernous sinus; 1, supraorbital branch; 2, muscular and lachrjTnal 

 branches ; 3, ciliary ; 4, anterior and posterior nasal or ethmoid ; 5, frontal ; 6, infra- 

 orbital ; H, facial vein ; 7, communication with the internal maxillary ; 8, external 

 nasal ; 9, angular, communicating at 10, with the frontal and supraorbital ; HI, ex- 

 ternal jugular vein commencing at the junction of IV, the temporal, and V, the internal 

 maxillary veins ; 11, meningeal branch ; 12, inferior dental ; 13, muscular ; 14, com- 

 munication between the facial, malar and infraorbital ; 15, placed in the spheno-maxillary 

 .fossa above branches coimected with the pterygoid plexus. 



