CHAPTER XIII 



OPERATIONS FOR CATARACT 



There are two principal operations for cataract — 

 discission and extraction. The former is employed only 

 in cases of congenital cataract, or when it is acquired 

 in early life, when the cataract is soft and undergoes ab- 

 sorption readily. 



Discission of Cataract. — The ultimate object of this 

 operation is to produce absorption of the lens by break- 

 ing up its substance by the use of a small knife-needle. 

 The eye should be washed with an antiseptic solution of 

 bichlorid of mercury, i : 5000, and the pupil dilated with 

 atropin solution of i per cent. It should then be anes- 

 thetized with cocain of 5 to 10 per cent, solution. The 

 speculum may be used, or an assistant may hold the 

 lids apart. The knife-needle is then passed through the 

 cornea near its margin — never through the center — 

 and pushed diagonally through the lens capsule and into 

 the lens substance. An upward and downward move- 

 ment of the handle causes the lens to be cut and broken. 

 The knife-needle must be withdrawn in the direct line 

 of its entrance. 



If absorption of the lens substance does not readily 



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