Contex OK® E-System

Contex OK® E-System lenses set the standard for overnight orthokeratology by offering the most advanced topography based fitting as well as empirical, trial or dispensable inventory sets. With no age restrictions, the Contex OK® Lens is the perfect option for active kids and teens that aren’t eligible for refractive surgery.

Features

• "Custom Designed" to Each Individual Cornea
• Reduces 5 Diopters of Myopia
• Proven Overnight Design
• Inventory Set Recommended

Simple Ortho-K, Expert Results

The OK® E-System's versatile, advanced design offers empirical quick and easy fitting for the novice as well as diagnostic and inventory fitting for the expert. Diagnostic and Inventory fitting can increase your first-fit success rate and reduce costly chair time.

Understanding Modern Ortho-K

The advanced OK® E-System proportionate lens design allows you to custom build a lens that will reduce up to five diopters of myopia gently and precisely molding the central epithelium while your patients sleeps.

Inventory Sets

Dispensable Inventory sets allow instant dispensing to most patients by using a simple cross-reference chart or the OK® Lens calculator. Our recommended sets are listed below.

OK® E-System Nomenclature

Example:
CK: 43.00/44.00 Refraction: -5.00 Eccentricity Value = .5

OK® E-System Design Code: 43.00/-5.00(.5e) / 9.06 / 10.6 / +1.00

If the Lens is Tight: Raise the e-value
OK E: 43.00/-5.00(.55e)          .05 loosens the fit by about 11 microns
OK E: 43.00/-5.00(.6e)          .1 loosens the fit by about 22 microns

If the Lens is Loose: Lower the e-value
OK E: 43.00/-5.00(.45e)          .05 tightens the fit by about 11 microns
OK E: 43.00/-5.00(.4e)          .1 tightens the fit by about 22 microns

For Additional Information

Download the Contex OK®-E System Quick Fit Guide. Download PDF

Or please contact one of our knowledgeable consultants.


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