CATARACT 



519 



'Jlie nucleus remains transparent, months or \-ears mav be 

 required for tlie ripening to be completed, it may become 

 stationary at any stage. 



1. The Incipient Stage. 



There are streaks of opacity from the cortex to the centre 

 of the lens where the streaks become narrower. Less 

 rarely there are dots or a general haziness. 



2. The Swelling Stage. 



The lens absorbs fluid, swells, pushes the iris forward 

 and so reduces the depth of the anterior chamber. The 

 cataract becomes stellate in appearance. 



3. The Mature Stage. 



The lens loses most of its fluid, shrinks, is completely 

 opaque, the anterior chamber is normal in depth, the 

 entire lens may be a hard '' black cataract." It is 

 now easily separable from the capsule and is "ripe," 

 ready for removal by extraction. 



4. The Hypercemic Stage. 



The mature stage continues or irregular spots may be 

 apparent. The lens may lose more fluid and mav 

 become a "shrunken" cataract, or soft and milkv, 

 and the nucleus sinks into the fluid which then equals 

 " Morgagnian " cataract. Lime salts (chalky cataract) 

 or cholesterin may be deposited. 



The anterior capsule may become thickened and opaque 

 (capsulo-lenticular cataract). 



TREATMENT. 



Extraction is the only means available, medicinal treatment 

 is useless. Atropine may temporarily assist vision in 

 some cases. 



Removal of both cataracts at the same time should never be 

 carried out. 



Artificial ripening may be resorted to so as to hasten the 

 process by incising the cornea, allowing the aqueous 

 humour to escape and the cornea to fall against the lens, 

 but such procedure is not free from risk. 



When is a Senile Cataract ready for Operation (?). Tests, 

 (i) Examine by focal illumination. 



If the opacity comes forward to the iris, so that the latter throws 

 no shadow on the lens, then the cataract is probablv mature. 

 (2) Cover one eye and throw a strong light suddenly upon the one 

 to be tested; the pupil should then contract. 



3Z 



