THE CEREBRAL VEINS 



655 



sinus, running for some distance in its walls. These veins freelj^ communicate with each other, 

 thus differing from the cortical arteries. They also communicate with the inferior cortical 

 veins. They may be roughly divided into (a) frontal; (b) paracentral; (c) ceiitral; (d) occipital. 

 (2) The inferior cerebral veins [vense cerebri inferiores] (fig. 518), ramify on the base of 

 the hemisphere and the lower part of its lateral surface. Those on the inferior surface of the 

 frontal lobe pass, in part into the inferior sagittal sinus, and in part into the cavernous sinus. 

 Those on the temporal lobe enter in part into the superior petrosal sinus, and in part into the 

 transverse sinus, passing into the latter from before backward. A large vein from the occipital 

 lobe winds over the cerebral peduncle and joins the great cerebral vein (of Galen) just before 

 the latter enters the straight sinus. One of the inferior cortical veins is called the middle 

 cerebral vein [v. cerebri media] ; it runs in the lateral fissure (of Sylvius) and ends in the cavernous 

 sinus. This vein is sometimes called the superficial Sylvian vein. Another, the great anasto- 



FiG. 518. — The Veins op the Brain, Inferior Surface. (After Toldt, 

 Anatomy," Rebman, London and New York.) 



'Atlas of Human 



Roots of the superior 

 cerebral veins 



Middle cerebral 

 vein 



Basal vein 



Saperior pe- 

 trosal sinus 



Opeaing of the in- 

 f er i o r cerebral 

 veins into the 

 transverse sinus 



Inferior cerebellar veins 



^i Inferior cere- 

 bral veins 



Anterior external 

 spinal veins 



Opening of the superior sagittal sinus 

 into the right transverse sinus 



Opening of the straight sinus into the 

 left transverse sinus 



Occipital sinus 



mosing vein of Trolard, a branch of the middle cerebral, establishes a communication between 

 the superior sagittal and cavernous sinuses by anastomosing with one of the superior cortical 

 veins. A second anastomotic vein, that of Labb6, is also a tributary of the middle cerebral, 

 and connects the veins over the temporal lobe with the transverse sinus. 



A small inferior cerebral vein, the ophthalmomeningeal vein, establishes a communication 

 between the cerebral veins and those of the orbit. It communicates with the veins of the base 

 and is usually drained by the superior ophthalmic vein. It occasionally opens into the superior 

 petrosal sinus. 



The central or deep (ganglionic) veins return blood from the internal parts of 

 the cerebrum, and converge to the great cerebral vein. 



