Yes, because we are fitting Irregular Corneas with the UltraHealth lenses it is necessary to achieve full clearance under the Vault and Under the Inner Landing Zone. You may use an OCT instrument to measure the clearance as well.
Once you achieve the proper clearance in the vault; observe the Inner Landing Zone to determine skirt curve. Use flattest skirt possible that provides slight clearance in the Inner Landing Zone (ILZ) and that has no wrinkling at the skirt edge.
Once you have the correct fit – over-refract to find your final lens power. Once you have over-refracted one lens your over-refraction will be the same for each lens. Add the over-refraction to the power of the diagnostic lens you wish to order.
Start with 255 Vault lens in UltraHealth FC diagnostic set. Appropriate fit is determined by increasing or decreasing vault, in 100 micron increments, to find first corneal touch under the vault area. Order first lens 50-100 microns over first touch.
Yes, because we are fitting UltraHealth FC lenses on Irregular Corneas, fluorescein is a valuable tool in identifying proper lens/cornea relationship. Desired fluorescein pattern will show 50-100 microns vault clearance with feather touch in the Inner Landing Zone (ILZ). You may use an OCT instrument to measure clearance, as well.
Once you achieve proper clearance in vault; observe the Inner Landing Zone (ILZ). If medium skirt provides slight clearance/feather touch in the ILZ, and the skirt has no wrinkling at the skirt edge, you are ready to order.
All lenses in the UltraHealth FC diagnostic set are calibrated to take same OR. Once you have determined lens vault – simply over-refract to find final lens power. Add the over-refraction to the power of the diagnostic lens you wish to order.
*Note: you cannot use an over-refraction done on an UltraHealth FC lens to calculate a standard UltraHealth lens order, and vice versa.