The Power of Range

When it comes to presbyopia treatment, the RayOne EMV provides uncompromising range and quality of vision

At the 35th Asia-Pacific Association of Cataract and Refractive Surgeons (APACRS 2023) annual meeting in Singapore, top surgeons from around the world presented on trending technologies in treating presbyopia in a Day Two session entitled “TRENDING TECHNOLOGIES – Highway to the Future.”

During the session, Prof. Graham Barrett (Australia) and Dr. Sri Ganesh (India) discussed monovision and capsulotomy-fixated IOLs, respectively. Prof. Barrett also shared the experiences that led to him collaborating with Rayner on developing the RayOne EMV, an FDA-approved, non-diffractive enhanced monovision IOL.

Treating presbyopia for cataract patients has become a key focus in ophthalmology in the last few years, with more choices now available beyond multifocal lenses.

The past decade-plus has seen a rise in the popularity of extended depth-offocus (EDOF) IOLs, which claim to give patients good distance, intermediate and near vision.

One of the newest EDOF offerings is the RayOne EMV lens, an extended range of vision IOL that is nondiffractive and utilizes positive spherical aberration to extend range of vision whilst avoiding issues that arise with diffractive lenses.

What makes the RayOne EMV lens different from other EDoF lenses is its optimization for enhanced monovision and a design that provides a smoother transition between distance and near vision.

A truly non-diffractive IOL

The RayOne EMV is an FDA-approved intraocular lens for presbyopia treatment, which provides an increased range of high-quality distance and intermediate vision and functional near vision with less dependency on glasses.

The EMV concept was developed by Prof. Graham Barrett and brought to market by Rayner, who produced the world’s first IOL in 1949. The RayOne EMV is the first and only lens of its kind, revolutionizing cataract results for patients worldwide.

In his talk at APACRS 2023, Prof. Graham Barrett explained that multifocal, trifocal and diffractive EDoFs often result in a compromise in optical quality including dysphotopsia, halos and glare. He showed how there are many choices for presbyopia and advised surgeons to consider what optical principle they think is likely to provide patients with a solution that allows for unaided near vision, thus giving them higher levels of postoperative satisfaction.

Compared to many other IOLs, the RayOne EMV lens offers several advantages. It provides excellent vision in low light conditions, reduces glare and halos and maintains excellent contrast sensitivity.

The RayOne EMV is a truly nondiffractive IOL that does not use light splitting technology like many IOLs that increase depth of focus. This results in desirably low levels of dysphotopsias similar to standard monofocal lenses.

The art of designing optics

During the session at APACRS 2023, Prof. Barrett said that he designed the EMV to be used with what he terms an enhanced monovision approach.

He and other surgeons have used a monovision approach for many years with regular monofocal IOLs. But now with the RayOne EMV, this monovision effect has been enhanced and true blended vision achieved.

A keen astronomer in his spare time, Prof. Barrett explained to the audience that using a telescope requires perfect quality and related this to mechanisms in the human eye.

“You can tell the quality of a telescope by moving the focus in and out while you focus on a single star. This, of course, reminds me of the adjustable focus of the human eye. But, unfortunately, when you implant an IOL, you no longer have this adjustable focus mechanism,” Prof. Barrett shared.

As an alternative to either a monofocal approach or splitting light into different foci, he presented the enhanced monovision IOL concept — a trending optical strategy in the treatment of presbyopia. In contrast to multifocal IOLs, enhanced monovision lenses create a single elongated focal point by adding a small amount of positive spherical aberration, rather than several foci, to enhance depth of focus.

“It’s really a balance between perfect resolution on the one hand, and adequate depth of focus [on the other]. Finding that elusive balance is the art of designing optics based on this principle,” he noted.

How does the RayOne EMV work?

The RayOne EMV is the only patented aspheric IOL that induces controlled positive spherical aberration. Compared to a lens with zero spherical aberration, the carefully-controlled positive spherical aberration induced by RayOne EMV spreads light along the visual axis, elongating the focal range from far to intermediate with up to 1.5 D of depth of focus with an emmetropic target. The great thing with the EMV lens is that even without the use of monovision, patients achieve excellent distance, intermediate and some near vision.

Most patients implanted bilaterally with this non-diffractive enhanced monofocal intraocular lens targeting micro-monovision ended up with good distance and intermediate vision, and many achieved spectacle independence.

The lens is thus designed to provide a smoother, blended transition between the eyes when compared to monovision with standard monofocals or other EDoFs, maintaining binocular stereoacuity and reducing asthenopia.

Achieving high-quality, spectacle-free distance vision

Dr. Sri Ganesh, chairman and medical director at the Nethradhama Super Specialty Eye Hospital, India, also spoke at the session on the new, innovative capsulotomy fixated IOL technology in the RayOne EMV.

Commenting on Prof Barrett’s talk, he said that as some patients face issues

such as dysphotopsias and night vision concerns with other IOLs, he recommends using the RayOne EMV.

“I started out using diffractive EDoFs… but then you have dysphotopsia and other issues. You always have some kind of compromise. What I find is that, with [the RayOne EMV], patients get the best spectacle independence,” he shared during the question and answer session.

As chair of the symposium, Prof. Barrett also commented that quality of vision is the most important thing and that an extended depth of focus can be achieved without diffraction by using positive spherical aberration.

While each patient’s needs are unique and need to be assessed before selecting an IOL, overall, Both Prof. Barrett and Dr. Ganesh concluded that the RayOne EMV is an excellent choice for patients undergoing cataract surgery, providing clear, high quality visual outcomes and an extended range of vision.