RIGID BITORIC LENSES

For patients with high amounts of corneal toricity, over 2 D to 3 D, it is often necessary to fit them with a toric base curve rigid lens to match the toric surface of the cornea.  A spherical base curve lens will not give a good physical fit.  

A spherical base curve lens on a toric 
cornea is like putting a section of a 
basketball (spherical surface) on the 
side of a football (toric surface)-they 
will not match.

Toric base curve RGP lenses will also 
have toric peripheral curves in order 
to maintain a round optical zone and 
give uniform peripheral clearance.  
With a toric base curve the front 
surface will have to be toric in most 
cases to give the patient the proper 
correction.