52 Surgical Diseases and Surgery of the Dog 



contract and diminish the equator of the eye, and this organ being 

 filled with liquid or semi-liquid, the cornea and retina become 

 separated, thus enabling focussing to take place. This view is sup- 

 ported by Randolph who points out that the dog is not possessed of 

 human visual acuteness, so that few demands are made on the ac- 

 commodative apparatus and consequently loss of the lens is at- 

 tended with comparatively little or no inconvenience. On the other 

 hand, Cocteau and Leroy in a series of experiments found that the 

 lens fibers were reformed in a certain length of time after their re- 

 moval. 



There are two methods of producing removal of a cataract in 

 the dog, viz., by Discission and by Extraction. The best results 

 attend discission, though this method is not adapted to cases of 

 senile or hard cataract. Discission comprehends the laceration of 

 the anterior capsule of the lens with a specially constructed needle, 

 so as to cause the aqueous humor to invade the spaces between 

 the lenticular fibers, which causes the latter to swell and gradually 

 soften and finally undergo absorption. The reparative process is 

 initiated by the surgeon, so to speak, and the rest is left to Nature. It 

 is followed by little or no irritation and an uneventful recovery is 

 the rule. Extraction or immediate removal is not always followed 

 by favorable results; it gives rise to considerable irritation during 

 the healing process and there is an ever-present menace that the 

 animal will irretrievably injure the eye in its efforts to allay this 

 irritation. Still, the operation has several times been performed 

 without untoward results. 



LUXATION OF THE LENS. 



This lesion occurs through traumatism or as a complication of 

 cataract. The congenital form has already been noted. It may be 

 complete or incomplete and take place into either the anterior or 

 posterior chamber. It necessarily causes partial or total abolition of 

 vision. 



Treatment. In anterior luxation the lens may be completely 

 removed by operative measures similar to those for cataract. 



STRABISMUS. 



GMnmonly termed "squint" this is a condition where the visual 



