382 Veterinary Medicine. 



tense opacity, white or yellow, and some bulging of the mem- 

 brane. 



The pus may be absorbed, or it may escape by rupture and 

 discharge externally, or into the anterior chamber when the re- 

 sistance is least in that direction, and when this takes place, a 

 dangerous internal infective inflammation is the result. 



In the slighter forms of keratitis the inflammation may come 

 early to a standstill, and recede, tenderness and photophobia pass 

 off, the eyelids may be opened, and the corneal opacities gradually 

 disappear. If any portion of the cornea has become vascular, that 

 portion is liable to remain opaque or even pink. 



Lesions. Under the influence of an irritant on the cornea, the 

 vessels in the margin of the sclerotic become actively congested 

 and pour out lymph freely, leucocytes also escape and with the 

 lymph pass through the lymph channels into the substance of the 

 corneal tissue. .Here they undergo active fission and increase, 

 and the normal cells of the corneal tissue multiply in like manner, 

 so that in a short time there is an extraordinary production of 

 embryonic cells. Into the embryonic tissue so formed, blood 

 escapes from forming loops of new vessels, and this goes on ex- 

 tending until the whole cornea may have become vascular. 

 Degenerations in the newly formed structure may result in sup- 

 puration, {hypopyonkerati.tis) or molecular decay and ulceration, 

 {ulcus cornea^ or organization may take place into the fibrous 

 tissue with contraction and permanent opacity, {macula) or a 

 hyperplasia may form in the shape of a staphyloma. 



Among the other complications may be named pus in the 

 anterior chamber (hypopion), prolapsus of the iris, iritis and 

 panophthalmia. 



Treatment. In the milder form of keratitis, antiseptic astrin- 

 gents with atropia sulphate are often effectual : zinc sulphate, 

 boric acid or alum (i : 100). Any direct mechanical cause of 

 the irritation must be removed, and the eye rendered as far as 

 possible antiseptic or aseptic. Derivatives also may be of ser- 

 vice, and Trasbot especially advises bleeding ' from the angular 

 vein of the eye but only in the very earliest stages. Cupping, 

 leeching or setons may be employed. Excessive tension may 

 be relieved by puncture of the cornea near its margin. The 

 remaining opacity after the inflammation has subsided may 



