CEREBRAL ANEMIA. 343 



there may be noticed occlusion of small vessels and alteration 

 of brain-structnre. 



Symptoms. — The indications of general cerebral anaemia 

 which may be observed in the more attractive of the forms 

 are such as are associated with a general weakened condition, 

 in this way forming part of the usual train of symptoms deve- 

 loped in general anemia. Early exhaustion under any work, 

 general pallor of visible mucous membranes, disposition to 

 syncope, impaired vision with constantly dilated pupils, with, 

 more rarely, want of perfect control over movements — such 

 may be noticed in young horses badly dieted, too early put to 

 Avork, and where sanitary conditions are adverse. In partial 

 ansemia the sjinptoms are neither diagnostic nor attractive ; 

 they are usually such as appear in association with plugging 

 of vessels, alteration of structure, and morbid growths, and vary- 

 ing according to the locality in Avhich the condition is situated. 



Treatment. — Only when the diseased condition is general 

 and dependent on general causes may we expect to treat with 

 hope of success. By attention to hygiene, good easily digested 

 food, light work and plenty of fresh air, we may improve the 

 quality and nutritive character of the blood. Of medicinal 

 agents the most approved are tonics, such as preparations of 

 iron combined with vegetable bitters. 



III. Cerebral Embolism and Thrombosis. 



The plugging of minute cerebral vessels with emboli, or as 

 the result of thrombosis, is probably of greatest interest in 

 a pathological point of view as the dkect inducing cause of 

 cerebral softening. Emboli, when occurring in the cerebral 

 vessels, seem to owe their existence mainly to the previous 

 occurrence of morbid depositions in connection with structures 

 acted upon by the blood-stream, as in some aged subjects with 

 warty valvular disease of the heart and some forms of pul- 

 monary thrombosis. Thrombi, again, have probably a more 

 extensive source of origin, chief of which are a diseased state of 

 the inner coat of the vessels, an unhealthy condition of the 

 blood itself, and a disturbance of the relations which in health, 

 ought to subsist between the tissues and the circulating 

 blood. 



As the result of either embolism or thrombosis there is im- 



