Glossary of Scleral Lens-related Terms

Contact Lens

The contact lens refer to either a soft or gas permeable lens that rests on the front surface of the eye. Many corneas with conditions such as keratoconus, post-refractive surgical complications, chronic dry eye, corneal dystrophies and disease and many other ocular conditions cannot support this type of lens. In other words, a "contact" lens has contact with the front surface of the eye, the cornea.


The clear front surface of the eye. The cornea is to the eye what a watch crystal is to your wristwatch.

Corneal Transplant Complications

Like all invasive procedures, corneal transplant surgery does have risks. It may take up to a year for the cornea to "seat" properly. In addition during the first year after the corneal transplant surgery is done, the contour and curvature of the cornea may change. Most patients who undergo a corneal transplant will need to wear a specialty contact or scleral lens for vision and ocular comfort purposes.


Post-LASIK Ectasia is a devastating complication of LASIK. This complication can occur weeks to years after the LASIK surgery is done. LASIK surgery thins out the cornea, which is the front surface of the eye. Because of the thinned out cornea, the pressure within the eye against the weakened corneal "wall" can cause the cornea to "buckle" or protrude. In other words vision will become severely compromised and the cornea will become distorted. There is no surgical or medical cure to restore the cornea to it's pre-ectasia condition. The only technology that will permit this eye to see clearly once again is a gas permeable scleral lens.

GVR Scleral lens

A GVR Scleral lens does not have contact with the front surface of the eye ( the cornea). Instead, the lens is supported by the white portion of the eye, known as the sclera. There is a space between the back surface of the scleral lens and the front surface of the eye. This space is filled with pure, unpreserved saline solution. In other words, the cornea is always in a liquid environment. We refer to our unique scleral lens as the GVR (Global Vision Rehabilitation Center) Scleral lens. This is because we design our scleral lens using proprietary software and computer imaging technology. We create the design and tell our laboratory exactly how it is to be made.

Gas Permeable Material

This is the material that our scleral lenses are made from. Oxygen from outside of the eye penetrates the scleral lens and enters to cornea. The cornea is the only tissue in our body that has no blood vessels. For this reason it is important that the correct materials are used to fabricate the lens and to design the lens so that no contact is made with the compromised cornea.


Keratoconus is a protrusion and thinning of the cornea. This can occur in the center or peripheral areas of the cornea. The end result of keratoconus is blurred, distorted vision than is best corrected with a specialty contact or scleral lens. Advanced cases of keratoconus can best be corrected with gas permeable scleral lenses.

Post-Refractive Surgical Complications

This refers to the unexpected loss of vision and ocular comfort that patients who have undergone LASIK, Radial Keratotomy, PRK and other vision altering eye surgeries have experienced. These complications include double vision, glare, halos loss of vision in low light situations, fluctuating vision, vitreous floaters and chronic dry eyes. Many of these conditions can take place years after the surgery was done.


The white portion of the eye.

The Wavefront Scleral Lens

The corneal irregularities created by refractive surgeries, such as LASIK and RK, are responsible for ghosting, halos, starbursting, and loss of contrast sensitivity. These "higher order aberrations" may exist on both the anterior and posterior. With aberrometry, the defects of the entire optical system can now be corrected by a scleral lens.

The Wavefront Scleral Lens

Autologous Serum for Dry Eyes

Dry eye conditions are among the most challenging conditions faced by refractive surgery patients. With autologous serum, blood is spun down to plasma, forming an eye drop that helps rehabilitate the cornea.

Learn More about Autologous Serum

Dr. Boshnick on CBS This Morning

See Dr. Boshnick and Dr. Morris Waxler (former FDA chief research scientist on refractive surgery) talk about bad LASIK

Optimum Infinite Gas Permeable Material

I am happy to announce that our Global Vision Rehabilitation Center will be designing and fitting all of our “high need” patients with the Optimum Infinite gas permeable contact lens material. The Optimum Infinite material is the most oxygen permeable material ever to be approved by the FDA. In addition, this newly FDA approved material includes a UV lens blocker. Now for the first time, with certain patients, wearing a scleral lens made with the Infinite material under extended wear conditions can be considered.

SMAP 3D Scleral Lens Design

NEW: Powerpoint presentation on SMAP 3D

Last year we introduced an exciting piece of technology that has allowed us to custom design a scleral lens much more accurately. It is the SMAP 3D, which is a computer attached to a dedicated camera that allows us to obtain a 3 dimensional image of the entire front surface of the eye, including the cornea and the surrounding white portion of the eye (the sclera). Up until now there has not been any technology that would allow us to measure the ocular curvatures outside the cornea. The SMAP allows us to do this. Read More

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Blurred Vision, Burning Eyes: This Is a Lasik Success?

EyePrint Pro

EyePrintPro technology creates a scleral lens based on a mold of the cornea. The molding is accurate to 1 or 2 microns and fits perfectly because it exactly mirrors the irregularities of the individual corneal surface. The technology is well suited for post-Lasik, Keratoconus, RK, eye injury, and corneal transplant patients. Read More in this PDF about EyePrintPro Scleral Lens Technology

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