362 DISEASES OF THE EYES. 



lens and iris may be pushed back into their normal position. In 

 large ulcers the iris is generally forced into the orifice, filling up 

 the opening and causing adhesions. When the fluid of the ante- 

 rior chamber collects again the lens and iris may be pushed back 

 from the cornea into their old position, but the section of the iris 

 which has united at the orifice remains adherent, so that the pupil 

 is pulled forward to the cicatrix of the sclerotic membrane, and the 

 power of vision of the eye is greatly impaired. Externally the 

 iris, which is drawn into the orifice, becomes covered with cicatri- 

 cial tissue, and by its contraction it forms a lobule of the iris. Tliis 

 finally contracts into a peculiar club-shaped body over the anterior 

 surface of the membrane (iris staphyloma). We must not confound 

 this condition with staphyloma pellucidam. By it we mean a 

 change of form in the sclerotic membrane, where it becomes more 

 or less opaque, and is forced outward in the shape of a grape-like 

 body by the dropsical condition of the anterior chamber. When 

 there is great irritation of the sclerotic membrane in some cases 

 we may have a prolapsus of the lens, and the eyeball subsequently 

 collapses, forming an opening in the centre of the eye which finally 

 becomes closed up by a whitish-gray cicatrix. 



Etiology. Besides the causes already mentioned in the forma- 

 tion of abscesses, the following also produce them : cauterization, 

 foreign bodies which adhere to the membrane, wounds in some 

 cases, etc. This disease may appear in the epizootic form with or 

 without distemper, and generally in connection with blennorrhcea 

 of the connective tissue. 



Prognosis and Therapputic Treatment. The prognosis 

 depends to a large extent on the irritation of the ulcer and the 

 rapidity of its progress. Ulcers which are small and located on 

 the borders are easier to treat than those which are larger and 

 located in the centre of the sclerotic membrane. In weak, badly 

 fed young animals and in pugs the prognosis is more unfavorable 

 than in healthy old animals. 



The treatment requires cleanliness and strict antiseptic remedies. 

 The use of a dressing is of great advantage, but few dogs can 

 be made to submit to one. In canine hospitals, as a rule, they 

 use a specially constructed leather cap (seen in Fig. 79). The 

 various antiseptic agents which are used are corrosive sublimate, 

 0.1, or chlorine water (either pure or mixed with two or three 



