538 DISEASES OF THE CORNEA 



infiltration or from an ulcer which has not perforated its 

 entire thickness. In keratectasia the iris is not involved as 

 in staphyloma. 



Treatment— Relieve the intra-ocular tension and apply a 

 compress. Iridectomy may be useful in some cases. 



Non-inflammatory Ectasia.— Two forms are recognized: 

 Keratoconus, and keratoglobus. 



Keratoconus.— A cone-shaped protrusion of the cornea 

 which does not become opaque. It results from a weakening 

 of the cornea at its center and an increase in intra-ocular 

 tension. The condition is incurable. 



Keratoglobus.— The entire cornea is enlarged as the result 

 of a general increase in size of the entire eyeball. It is seen 

 in hydrophthalmus. The cornea retains its transparency. 

 The condition is usually congenital and most often observed 

 in young dogs and young cats. 



Treatment.— ~No treatment is of any value. 



TUMORS OF THE CORNEA. 



Tumors of the cornea are rare in animals. Dermoids are 

 occasionally met with in dogs and cats. Sarcomas and 

 carcinomas have been noted. They usually originate either 

 in some other part of the eye or in adjacent tissues. 



Treatment.— Surgical treatment should be attempted as 

 early as possible. No treatment should be attempted in 

 malignant tumors. 



