142 PRACTICE OF MEDICINE. 



The paralysis following cerebral hemorrhage presents great varie- 

 ties with respect to its seat, and pathological anatomy is far indeed 

 from being always able to assign the cause of such numerous 

 varieties. 



There has not as yet been established any sj^ecial relation be- 

 tween the seat of the effused blood and the paralysis of par- 

 ticular organs. It has been asserted that paralysis of the superior 

 extremities depends on the effusion taking place in the thalami, or 

 in the cerebral substance situated on a level with, and posterior to 

 them ; and that paralysis of the inferior extremities depends on the 

 effusion taking place in the corpora striata^ or in the cerebral sub- 

 stance situated on a level with, or anterior to them. It is certainly 

 true that cases occur in which the relation of the effusion and the 

 paralysis as above stated holds good ; but again, there are numerous 

 cases which fully demonstrate, that paralysis of the extremities has 

 no necessary connexion ivith effusion into these portions of the brain. 



It has also been asserted that loss of speech depends on the effusion 

 occupying the anterior lobes of the brain ; but this observation derives 

 still less support from actual experience than the former, for blood 

 may be effused in the anterior lobes of the brain without giving rise 

 to any modification of speech. 



The best established facts regarding the seat of cerebral hemor- 

 rhage, and the relation which exists between it and paralysis, are the 

 following : — 



1. That the paralysis almost always occupies the side of the body 

 opposite to that of the brain or cerebellum in which the effused blood 

 is situated. 



2. That the paralysis affects only one side of the body when the 

 effused blood is confined to one hemisphere of the brain, or one of 

 the lateral lobes of the cerebellum. 



3. That the paralysis exists on both sides of the body when the 

 hemorrhage has taken place in both hemispheres of the brain, or 

 both lateral lobes of the cerebellum, into the ventricles, the pons 

 Varolii, the medulla oblongata, and on the surface of the brain. 



4. That paralysis of both sides of the body may also take place 

 when the hemorrhage is confined to one hemisphere of the brain or 

 lateral lobe of the cerebellum, but is so extensive as to produce com- 

 pression of the opposite hemisphere or lobe. 



A most remarkable circumstance, connected with cerebral hemor- 

 rhage, has been observed by Andral — viz., hemorrhage of one of 

 the lobes of the cerebellum, like that of one of the hemispheres of 

 the brain, gives rise to paralysis of the opposite side of the body ; 

 but if hemorrhage takes place into the left lobe of the cerebellum, 

 and right hemisphere of the cerebrum, the paralysis is found to 

 exist on that side opposite to the hemisphere of the cerebrum, which 

 is the seat of the effusion, the other side remaining unaffected by the 

 effusion in the cerebellum. 



