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00086_Field_86.txt
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1997-10-28
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21 lines
BIFOCAL CONTACT LENSES
SEGMENT DESIGNS
Advantages of segment lenses:
-good distance and near vision
-can get high add powers
Disadvantages of segment lenses:
-patient does not have good near vision in upgaze
-thick lens due to the prism-can cause comfort
and edema problems
-fairly complicated lens to fit
-patient must have the correct ocular anatomy
-only available in RGP designs
(hydrogel lenses do not translate enough)
-expensive