HYDROCEPHALUS ACQUISITUS. 277 



and depression as those of incomplete and gradually-developing anaemia, 

 [f, at the same time, we remember that those portions of the brain 

 bounding the ventricles are destroyed, in acute hydrocephalus, by soft- 

 ening, in the chronic form by atrophy, and that this may induce partial 

 paralysis, we may construct a picture of the disease, either in the acute 

 or chronic form, exactly corresponding with direct observation. 



Sudden and large effusions of serum into the cerebral substance 

 and ventricles lead to a combination of symptoms which, from its re- 

 semblance to the apoplectic attack induced by extravasation of blood, 

 is usually termed apoplexia serosa. 



After what was said above, it is hardly worth mentioning that a 

 distinction between serous and sanguineous apoplexy is not by any 

 means possible in all cases, and that, if a diagnosis be made, it is 

 chiefly from the etiology, which indicates one form rather than another. 



In children, acute hydrocephalus almost always runs its course with 

 the symptoms that we ascribed to high grades of cerebral hyperaemia, 

 and to the first stages of acute meningitis. Severe attacks of convul- 

 sions, with loss of consciousness, are the most frequent and character- 

 istic symptoms. If these attacks occur very often, and last unusually 

 long, they should excite the fear that the hyperaemia has induced con- 

 siderable transudations in the ventricles, and it is to be feared that the 

 transudation will not be absorbed, or, at least, only partly so, and that 

 chronic hydrocephalus will remain. 



The symptoms of chronic hydrocephalus either succeed those of the 

 acute form, or they develop insidiously and gradually. They consist 

 of headache, dizziness, weakness of the special senses, particularly of 

 the eyes, very often of a general paresis, preceded by a tottering gait 

 and trembling of the limbs. Among the constant symptoms are dis- 

 turbances of the intellect, especially its gradual loss, even to idiocy. 

 This is sometimes accompanied by convulsions, and occasional vomit- 

 ing. The patients usually have a slow pulse, are readily chilled, are 

 occasionally ravenous ; they have a puffy look, and varicose vessels on 

 the cheeks. Of course, these symptoms only render the diagnosis of 

 chronic hydrocephalus certain when other cerebral diseases, accompa- 

 nied by similar symptoms, can be excluded, and, consequently, that 

 the diagnosis can rarely be made with absolute certainty. The course 

 of the disease is usually very tedious. If death do not sooner occur 

 from some intercurrent disease, it finally results, sometimes rapidly and 

 unexpectedly, from acute increase of the effusion, sometimes slowly, 

 from its gradual increase, being usually preceded, for some days, by 

 continued deep sopor. 



TREATMENT. The treatment of acute hydrocephalus is the same 

 as that of acute hyperaemia of the brain and acute meningitis. In 



