772 Epilepsy. 



or cortical epilepsy, in which besides loss of consciousness the 

 spasms always aft'ect the same group of muscles, and then pro- 

 ceed to attack the other muscles successively. 



Course. True epilepsy is a chronic affection that causes 

 a continued predisposition to periodically recurring attacks of 

 convulsions. The attacks come on, however, at different inter- 

 vals ; in many animals few attacks are noticed during the whole 

 course of life, but in others seizures may occur weekly, daily 

 or several times a day. Their appearance sometimes seems to 

 depend on external influences, and again they follow in short 

 periods without any apparent cause. It seems as if at first the 

 attacks were less frequent but longer, and later more frequent 

 but of shorter duration. In the most severe cases the attacks 

 follow each other quickly and the condition of the animal be- 

 comes such that consciousness does not return in the intervals 

 (status epilepticus) ; in such cases the convulsions themselves 

 can cause death, whilst ordinarily severe epilepsy may cause 

 the animal to injure itself fatally when collapsing. In some 

 animals the attacks are at times very frequent, then they subside 

 for a long time, even for several months, whereupon several 

 attacks occur at short intervals and then disappear for a longer 

 period. 



Whether true epilepsy in animals is curable, can not be 

 decided by the clinical observations, but a predisposition for 

 further attacks of convulsions appears to persist invariably. 



The course of secondary epilepsy depends on the under- 

 lying disease. 



Diagnosis. For the recogiiition of genuine epilepsy the es- 

 tablishment of the chronicity of the affection appears to be of 

 primary importance, but due weight must be given to whether 

 during the periods between the attack the animal exhibits any 

 organic disease of the brain or other diseased condition which 

 stand in causal relation to them. If investigation in this re- 

 spect leads to a negative result, but the attacks of spasms are 

 always accompanied by loss of consciousness, the nature of 

 the complaint is not hard to recognize. Limited or general 

 tonic-clonic contractions have been observed in acute diseases 

 of the brain, in many infectious affections (distemper), also in 

 certain cases of poisoning. But in these cases symptoms of 

 the underlying disease are present also in the intervals be- 

 tween convulsions, which are usually short, and moreover the 

 diseases always take an acute course. The last mentioned con- 

 dition differentiates also the socalled eclampsia of the bitch 

 from epilepsy, and moreover the close connection of eclampsia 

 with parturition will reveal the nature of the complaint. 



It is much more difficult to differentiate in a given case 

 between true epilepsy and an epileptoid attack (secondary and 

 reflex epilepsy) ; but since prognosis as well as the course of 

 treatment will depend on a clear understanding of this point, 



