408 DISEASES OF THE EYES 



or last for weeks. In the latter case we observe the formation of blood 

 vessels at the border of the cornea and the sclerotic membrane. These 

 blood vessels increase in size and the edges become very vascular, and 

 during vascularization of the cornea it is not rare to see hemorrhages 

 in that tissue followed by a number of brownish-black pigment spots, 

 and occasionally the cornea remains permanently opaque and even 

 vascular. Froehner describes a superficial purulent affection of the 

 cornea as an effect of purulent keratitis or as a secondary symptom of 

 distemper; this is indicated by a roughened appearance of the cornea, 

 and a yellowish opacity of the cornea due to pus corpuscles. 



Therapeutics. — The treatment is the same as in inflammation of 

 the conjunctiva — that is, washing and painting with a solution of sul- 

 phate of zinc, corrosive sublimate, alum, or sulphate of copper, boracic 

 acid, or the oxide of mercury salve; where there is great pain and photo- 

 phobia use solutions of cocaine or acoin. Avoid all use of lead solutions 

 in such cases where there is any loss of substance of the cornea, as the 

 lead is deposited in the ulcer and produces black-colored spots which are 

 permanent. If there is any ulceration, we must apply the therapeutic 

 treatment as indicated in ulcerative keratitis, and in cases where the 

 spots on the cornea remain use the treatment given under the same 

 heading. 



Peritomy. — This operation is recommended in pannus, that con- 

 dition where there is vascularization of the cornea, and after massage, 

 stimulating salves and hot-water compresses have been tried and failed. 

 The animal must have a few drops of a 4 per cent, solution of cocaine 

 put into the eye, and the lids held back by an assistant; then the affected 

 surface of the cornea is carefully scarified, or curetted by means of the 

 edge of a sharp knife. Great care must be taken to hold the knife at right 

 angles to the eye, as the slightest slip or struggle on the part of the animal 

 misplacing the position of the knife will cut through the cornea. The 

 surface must be carefully scraped until all of the vessels are removed from 

 the surface of the cornea. Frick recommended making a direct incision 

 in the cornea. He fixes the eye and by means of a very sharp knife, pares 

 off the aljnormal formation, even cutting down half through the body of 

 the cornea, treats it with boric acid solution, and generally has a cure 

 in a few days. 



(2) Keratitis Profunda or Keratitis Parenchymatosa. Deep Paren- 

 chymatous Inflammation of the Cornea. — This affection may be circum- 

 sicribed or diffuse. In the former it is due to some external traumatism 

 directly on the corneal membrane; in the latter, the diffuse condition is 

 due to some infectious disease such as distemper, or, in certain cases, 

 fever is the only other symptom present. The surface of the cornea 

 has an opaque, dull, slightly grooved condition, the color bluish-gray 



