CATARACT. 



73 



operation an instrument termed a cystotome is passed into the 

 anterior chamber at the margin of the cornea in the direction 

 of the lens, which it scratches several times in such a way as 

 to lacerate its capsule. This procedure may have to be re- 

 peated two or three times at intervals of a month or six weeks, 

 the lens itself ultimately undergoing a process of absorption. 

 The second operation consists in the removal of the entire 



Fig. 43. 

 Graefe's cataract knife. 



lens. A special pattern of knife (usually Sichel's or Graefe's) 

 is used in order to puncture the cornea, an entrance being 

 effected on its conjunctival margin, and the point pushed 

 through some distance further along, the intervening portion 

 of cornea, together with a thin slice of the conjunctiva, being 

 incised. The aqueous humour is allowed to escape, and the 

 capsule of the lens is scratched with a cystotome as described 

 above ; gentle pressure with the finger and thumb is put upon 



Fig. 44. 

 Cystotome and curette (Graefe's). 



the eyeball, and by the aid of a cataract spoon or curette the 

 lens is slowly and carefully forced out through the corneal 

 orifice. More antiseptic lotion is then applied, the eyelids 

 being kept closed and covered with an antiseptic pad. 



After-treatment consists in keeping the patient in a 

 darkened kennel, and as quiet as possible for about- a fort- 

 night or so, the antiseptic pad being changed once or twice a 

 day. 



