In Focus Blog

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SynergEyes In Focus Blog

At SynergEyes, we pride ourselves in delivering contact lens products that improve vision and ultimately enhance the quality of everyday life.

This blog is geared towards practitioners to highlight case studies from your peers and covers topics such as fitting & troubleshooting, as well helpful articles on practice management and the handling and care of SynergEyes lenses like Duette and UltraHealth.

A Lens Designed to Fit True Scleral Shape

By Amy Hellem

SynergEyes has long been known as a hybrid specialty contact lens company, but after discovering a truly unique scleral lens designed by the leading contact lens authority in Europe, the company wisely chose to spread its wings and enter the scleral lens space.

Design Origins

The company’s scleral lens, called the SynergEyes VS™, was designed by acclaimed scleral lens authorities at Visser Contact Lens Practice, in association with NKL in the Netherlands. NKL Contact Lens is Europe's leading specialty contact lens manufacturer and is a wholly owned subsidiary of Menicon Co., Ltd., a worldwide leader in the development of lens materials, designs and lens care solutions.

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The Visser name is associated with forward-thinking clinical circles worldwide. In fact, Visser’s groundbreaking work brought the concept of bi-tangential (nonrotationally symmetrical) contact lenses to life and is the basis for the SynergEyes VS lens design.[1] By incorporating a tangential periphery, as suggested by Visser, you can achieve gentle positioning on the scleral surface, increase fitting tolerance, and optimize centration.[2]

In the past, most researchers and clinicians assumed that, like the cornea, the sclera features a curved shape.[3] But, as they looked more closely at maps and molds of the eye, they discovered that, from the peripheral cornea onward, the sclera often continues in a straight line, meaning it’s tangential.[4] Research data also suggests that toricity is more pronounced in the scleral area than in the limbal area, irrespective of the toricity of the cornea.[5]

Recognizing that this has a tremendous impact when designing lenses that are meant to rest on these zones, SynergEyes partnered with NKL to bring this innovative bitangential scleral lens to the United States.

Lens Properties

The SynergEyes VS lens is an innovative scleral lens with a distinctive bi-tangential[6] periphery designed to accommodate a wide variety of corneal conditions. This fully vaulting lens takes into account the curvature of the cornea, limbus and sclera. It is a back surface toric that allows for front-surface cylinder, which can greatly improve vision in patients with residual astigmatism.

The bi-tangential periphery of the SynergEyes VS aligns with the flatter more toric sclera creating ease of landing and stability. Two adjustable landing zones that are 90 degrees apart accommodate the toric sclera and improve centration.[7] The adjustable flat or steep meridian of the bitangential design aims to distribute the lens pressure more equally over the sclera and improve the scleral lens fit, with less risk of air bubble formation behind the lens, or local blanching of the conjunctival scleral vessels.[8]

According to Visser, “the latter disadvantages occur with rotationally symmetrical scleral lenses fitted to toric or irregular anterior scleral surfaces because the edges are locally too flat or too steep.”[9]

SynergEyes VS is available in two materials. Menicon Z has extraordinary levels of oxygen permeability with a hyper-Dk of 163 and higher, resistance to breakage and scratches, and excellent deposit resistance compared to other hyper Dk materials. The lens is also available in Optimum Extreme from Contamac, with a Tangible Hydra-PEG coating option.

Candidacy and Integration

The SynergEyes VS offers a straightforward fitting method that addresses a majority of corneal irregularities and scleral shape. It is recommended for patients with keratoconus, pellucid marginal degeneration, post-keratoplasty, post-refractive surgery, trauma and irregular astigmatism, ocular surface disease, high refractive error and dry eye.

The Journey to Clinical Practice

It may come as a surprise that our knowledge of scleral shape has been looked at for over a decade. In fact, it was described in 2006 by Esther-Simone Visser who, together with NKL, developed the SynergEyes VS Scleral Lens.[10][11][12] Like Visser, SynergEyes recognized that scleral lenses need to do more than vault the cornea; they need to fit the sclera.

Until now, scleral shape has not guided fitting philosophies, which makes many fitters feel like they’re sometimes trying to fit a square peg in a round hole. Even in the best of circumstances, it’s seldom perfect. But the days of trying to work around what science has taught us about scleral anatomy are behind us. Now, with the SynergEyes VS, you can define parameters based on the eye’s true shape.

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Amy Hellem is an independent writer and researcher who specializes in ophthalmology and optometry. Previously, she served as editor-in-chief of Review of Optometry and Review of Cornea & Contact Lenses and directed the custom publishing division for Review of Ophthalmology.

References

[1] Visser ES, Van der Linden B, Otten H, Van der Lelij A, Visser R. Medical applications and outcomes of bitangential scleral lenses. Optometry and Vision Science 2013;90:1078–85.

[2] Visser ES, Van der Linden B, Otten H, Van der Lelij A, Visser R. Medical applications and outcomes of bitangential scleral lenses. Optometry and Vision Science 2013;90:1078–85.

[3] Van der Worp E, Graf T, Caroline P. Exploring beyond the corneal borders. Contact Lens Spectrum 2010;6:26-32.

[4] Van der Worp E, Graf T, Caroline P. Exploring beyond the corneal borders. Contact Lens Spectrum 2010;6:26-32.

[5] Van der Worp E, Graf T, Caroline PJ. Exploring beyond the corneal borders. Contact Lens Spectrum 2010; 25 (6):26–32.


[6] Visser, Medical Applications and Outcomes of Bi-tangential Scleral Lenses. Optometry and Vision Science VOL. 90. NO.10, Oct. 2013

[7] Data on file.

[8] Visser ES, Van der Linden B, Otten H, Van der Lelij A, Visser R. Medical applications and outcomes of bitangential scleral lenses. Optometry and Vision Science 2013;90:1078–85.

[9] Visser ES, Van der Linden B, Otten H, Van der Lelij A, Visser R. Medical applications and outcomes of bitangential scleral lenses. Optometry and Vision Science 2013;90:1078–85.

[10] Visser ES, Visser R, Van Lier HJ. Advantages of toric scleral lenses. Optom Vis Sci 2006;83:233Y6.

[11] Visser ES, Visser R, van Lier HJ, Otten HM. Modern scleral lenses. Part I: clinical features. Eye Contact Lens 2007;33:13Y20.

[12] Visser ES, Visser R, van Lier HJ, Otten HM. Modern scleral lenses. Part II: patient satisfaction. Eye Contact Lens 2007;33:21Y5.