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MANUAL OF EQUINE MEDICINE. 



It is followed by the stage of depression, which is charac- 

 terized by stupor and coma, caused by more serious involve- 

 ment of the true nerve-centres. 



The differences between cerebral and meningeal diseases 

 in the human subject are arranged as follows by Aitken : — 



Cerebral Disease. 



1. From the outset, or from a 

 very early stage of development, 

 there is loss of some one or more 

 of the proper nervous functions, 

 such as paralysis, anaesthesia, loss 

 of memory. 



2. Cerebral disease is not com- 

 monly attended by high-marked 

 exaggeration of function, such as 

 furious delirium, convulsions, in- 

 tense hypersesthesia or tenderness. 



3. Little vascular excitement 

 attends cerebral disease, nor is 

 there frequently any highly - 

 marked general disturbance. 



4. Paralysis and anaesthesia, 

 losses of volition, ideation, per- 

 ception, and the like, characterize 

 cerebral disease. 



Meningeal Disease. 



1. It is not till some time after 

 the detection of signs of disease 

 that diminution or loss of nervous 

 function takes place. 



2. The subsequent diminution 

 or loss of nervous function, which 

 succeeds the prolonged existence 

 of 'head symptoms,' is generally 

 preceded in cases of meningeal 

 disease by extremely severe ex- 

 citement or exaggeration of func- 

 tions, such as pain, tenderness, 

 furious delirium, or convulsions. 



3. In meningeal affections there 

 is usually much local vascular ex- 

 citement, with general distur- 

 bance. 



4. Spasms or convulsions, pain 

 and delirium, are the general 

 features of meningeal disease. 



Morbid Anatomy. — When the membranes of the brain 

 are involved in the inflammation, the pia mater is thickened, 

 opaque, and much congested over a larger or smaller area. 

 The dura mater may be adherent in parts to the cranial 

 bones. 



Inflammation of the brain itself is usually limited to one 

 or more patches, and, as in man, is more commonly met 

 with as the result of injury or disease of the cranial bones. 

 The inflamed brain-substance is sometimes much altered, 

 but may be at first red and congested, afterwards becoming 

 pulpy and disorganized, with congestion and oedema of the 

 surroundino; nerve-tissue. 



