Keratoconus

Fits All Types of Keratoconus

• Aspheric Design
• 3 Point Touch Fit


The AS-20H lens utilizes a high eccentricity value. This allows us to fit a steep base curve so the lens will rest lightly on the cone but it also gives us a light touch in the periphery to balance the pressures. The first lens should be fit about five diopters steeper than flat K. 

These tips should help you achieve a successful fit

1. Light touch on cone.
2. The lens should center between the apex of the cornea and the cone.
3. Peripheral clearance is a must to promote tear exchange to the cone.
4. The lens must display adequate movement on the blink.
5. The best starting overall diameters are 10.0 - 10.2mm.
6. Trial fitting is a must for best success.

If Indicated Lens is Too Tight:
Flatten the Base Curve by ½ diopter

If Indicated Lens is Too Loose:
Steepen the Base Curve by ½ diopter

Example:
CK’s: R: 48.00/52.00          Refraction: -6.00          Eccentricity Value = .72          
        L: 49.50/53.00          Refraction: -7.00          Eccentricity Value = .79

          R: Base Curve: 6.37          Lens Power: -10.62 (w/vertex)
          L: Base Curve: 6.19          Lens Power: -11.50 (w/vertex)

For Additional Information

Download the AS-20H Fitting and Information Sheet. Download PDF

Or please contact one of our knowledgeable consultants.

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