I50 OPHTHALMOLOGY FOR VETERINARIANS 



cannot be disengaged readily, it may be pushed along, 

 slightly tilting the point of the knife forward, until it 

 again emerges into the anterior chamber, to the op- 

 posite corneal margin at the point of counterpuncture. 

 This accident is usually due to a shallow anterior cham- 

 ber and lack of skill. Always keep the knife-blade in 

 view, in the anterior chamber, between the cornea and 

 the iris. When the iris is punctured or cut, hemorrhage 

 in the chamber is likely to follow. This occludes one's 

 vision, but, as a rule, does no harm, as it is stroked out 

 with the lens or is absorbed soon after the operation is 

 completed. When the iris is cut, an iridectomy will 

 have to be done to get the best visual results. 



Prolapse of the iris sometimes occurs when a large 

 portion of this body passes through the corneal wound. 

 In the majority of cases this can easily be replaced 

 by the shell-spoon or replacer. If it cannot be so replaced, 

 it must be grasped with the iris forceps and cut off near 

 the wound. 



The lens capsule may also be cut in the passage of the 

 knife through the anterior chamber. This weakens the 

 resistance, and pressure of the lids or too much pres- 

 sure upon the eyeball with the fixation forceps may 

 cause the lens to be delivered spontaneously as soon as 

 the corneal section is completed. If no vitreous follows 

 this accident, the operation may be completed in the 

 usual way. If vitreous escapes when the lens is ex- 

 tracted, the speculum should be immediately removed 



