530 DISEASES OF THE CORNEA 



facets occurring singly or multiple. This disease has been 

 observed quite often in certain breeds of dogs but is very 

 rare in cats and birds. 



Etiology.— Nothing definite is known in regard to its 

 etiology. Dogs with , prominent eyes are often affected. 

 It has been observed to accompany or follow rheumatic 

 affections. It may be due to injuries, infections, specific or 

 general, or exposure. 



Symptoms.— Cloudiness of the cornea is the earliest symp- 

 tom. This is followed soon by small, opaque, white, gray 

 or yellow spots which penetrate into the parenchyma of the 

 cornea. Ulceration of one or more turbid areas may take 

 place causing small facets to appear. Injection of the- 

 conjunctiva and scleral membranes is a prominent symptom 

 which may gradually disappear as the case becomes chronic. 

 Lacrimation and photophobia are frequently seen. Owing 

 to the disturbance of the cornea it will have a shagreened 

 appearance. 



Prognosis and Course.— The course of the disease is chronic. 

 The symptoms may almost completely disappear only to 

 recur. Some cases show a tendency to become periodic. 

 The prognosis, therefore, should not be made too favorable. 

 Treatment.-- Flush the cornea with boric acid (2 per cent.), 

 chinosol (1-500), or silver nitrate solution (| per cent.). 

 This should be followed immediately with a few drops of a 

 solution of succus cineraria maritima compositus (50 per 

 cent.). This treatment should be continued for several days 

 or weeks to obtain the best results. Some of the ophthalmic 

 ointments may be tried in obstinate cases. 



Parenchymatous Keratitis.— Definition.— An inflammation 

 of the parenchyma of the cornea, characterized by a diffuse 

 infiltration of the interstitial tissue with a vascularization 

 of the sclera. It is accompanied in most cases by irido- 

 cyclitis. Parenchymatous keratitis is a very common 

 affection in dogs but rare in cats and birds. 



Etiology.— Infection is an important factor. In dogs it 

 follows or accompanies distemper. It may be due to a 

 spread of inflammation from the iris (iritis), choroid (choroid- 

 itis), etc. Chronic eczema, mange, etc., when they affect the 



