262 DISEASES OF THE BRAIN. 



marasmus and hydreemia which developed toward the end, partly from 

 ntercurrent diseases. 



Treatment is fruitless against this affection ; it can only be of use 

 in combating the more severe symptoms. 



CHAPTER XIII. ^ 



TUMORS OF THE BRAIN AND ITS MEMBRANES. 



UNDER the head of tumors of the brain are included growths and 

 parasites occurring in the skull, and aneurisms of the cerebral arteries. 

 We shall follow this custom, since it is very convenient on account of 

 the great correspondence of the symptoms due to these otherwise dif- 

 ferent diseases. 



ETIOLOGY. The pathogeny and etiology of cerebral tumors is very 

 obscure. This is true not only of carcinoma, sarcoma, glioma, and myx- 

 oma, but also of the rarer tumors, cholesteatoma or pearl tumors, lipoma, 

 and cystoid growths. Cancer of the brain occurs chiefly in advanced 

 age ; it is sometimes primary, and then usually remains the only carci- 

 nomatous disease in the body ; sometimes it is secondary to carcinoma 

 of other organs. The other neoplasia that we mentioned above, also 

 occur chiefly, but not exclusively, in advanced age, and according to 

 statistics are more frequent in males than in females. We know 

 nothing of the morbid predisposition or the exciting causes to which 

 these neoplasia are due. They have been frequently observed after 

 precedent injuries of the head ; but in such cases there is no certainty 

 of a genetic connection between the injury and the growth. We must 

 bear in mind how frequently slight injuries of the head occur, and how 

 carefully they are inquired after, in any patient suffering from symp- 

 toms of brain-disease, and, when found, how strong the inclination is at 

 once to refer the disease to them. 



Tubercles in the brain with rare exceptions occur in children, and 

 chiefly in those over two years old. They are rarely primary ; but 

 almost always form complications of the so-called tuberculosis of the 

 lymphatic glands, and of pulmonary tuberculosis. 



Cysticerci and echinococci of the brain, as of other organs, depend 

 on the emigration of the embryos of these parasites. 



Aneurisms of the cerebral arteries are usually due to degeneration 

 of the arterial walls from endarteritis deformans. 



ANATOMICAL APPEARANCES. Carcinoma of the brain is usually in 

 the form of round or lobulated, generally circumscribed tumors, with 

 tne softness and other peculiarities of medullary cancer ; more rarely 

 they have the firm tissue of scirrhus, and then they usually pass into 

 the neighboring cerebral substance without having any distinct bound 



