THINNNED ZONE STABILIZED TORIC LENSES

Hydrogel toric lenses may be prevented 
from rotating by thinning the top and 
bottom portion of the lens instead of 
using prism.  The thin portions of the 
lens stay under the lid margins.  If the 
lens rotates such that the thin zones 
are horizontal, when the patient blinks 
the lid will hit the 
thicker portion on 
the side where the 
lens has rotated up 
and will push it back 
down to keep the 
lens aligned.

Thin zones can be 
used in place of 
prism.