Conforma-K™ ... the ultimate in GP Keratoconus Lens Design


What is Conforma-K™ ?

The Conforma-K design has an ellipsoidal posterior surface that gradually flattens in all meridians from the optic center to the lens edge. This progressive flattening minimizes localized bearing points resulting in improved alignment and comfort. Improved lens to cornea alignment provides a more uniform tear film and efficient masking of irregular astigmatism. Traditional multicurve Keratoconus designs flatten in multiple steps creating numerous potential pressure points resulting in tear film and comfort obstacles. With Conforma-K these fitting obstacles are minimized.

Conforma-K Lenses provide even distribution of bearing pressure

The aspheric posterior surface of the Conforma-K lens not only enhances the lens to cornea fitting relationship, it also provides a larger functional optic zone reducing flare and ghosting. The aspheric surface also minimizes peripheral aberrations and residual astigmatic error. Conforma-K lenses will normally center over the apex of the cone but the large optical zone area will normally provide ample pupil coverage.

How can one eccentricity fit most corneas ?

Conforma-K corneal lenses are available in a .65 eccentricity (peripheral flattening factor). However, using the same eccentricity value but changing the base curve value also changes the peripheral flattening since the base curve denotes the magnitude or size of the ellipse (hence, a steeper base curve will have a slightly steeper periphery and, conversely, a flatter base curve will have a flatter periphery).


The two ellipses have the same eccentricity and are identical in shape, one is twice the size (linear dimension) of the other. The magnitude of the larger, given by r (base curve radius) is twice that of the smaller. Note how a change in base curve or overall lens size will affect peripheral fit.

Conforma-K lenses with .65 eccentricity allows the ens to be fitted appreciably steeper for better entration while the less curved periphery is directed in a more downward, long, cone-like direction, thus paralleling the anomalous cornea.

Controlled Edge Lift

The Conform-A-Spheric will help the lens fitter control edge lift and tear exchange. There are three edge lift options available, CAS 121, 141, 161. The CAS 121 is the steepest of the 3 and will reduce edge lift and tear exchange. The CAS 141 is a mid range appropriate for the average fit. The CAS 161 is the flattest of the 3 and will increase edge lift and tear exchange.