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 new and innovative technologies in treating presbyopia.
During the session, Prof. Graham Barrett (Australia) shared his insights on the RayOne EMV, an FDA-approved, non-diffractive IOL which he designed for the treatment of presbyopia.
Treating presbyopia for cataract patients is now becoming a key focus in ophthalmology, with more options becoming available today when they previously consisted of monofocal lenses and multifocal lenses that split light.
While monofocal lenses provide focus at one distance only, multifocal lenses allow for vision at a range of distances — correcting near, intermediate, and far distances.
Now, there are extended depth-of-focus (EDoF) IOLs.
In contrast to EDoF lenses are EMV lenses – an enhanced monovision IOL or extended range of vision IOL that is non-diffractive and utilizes positive spherical aberration to uniquely extend vision whilst avoiding issues that can arise with diffractive lenses.
What makes the EMV lenses different from EDOF lenses is that they enhance monovision and are designed to provide 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, intermediate and near vision with less dependency on glasses.
Developed by Rayner, which produced the world’s first IOL in 1949, the RayOne EMV is the first and only lens of its kind, revolutionizing monovision results for patients worldwide.
Where monovision increases your distance, intermediate, and near vision, the RayOne EMV is designed to extend your depth of focus for higher quality, uninterrupted vision throughout the entire intermediate and distance visual range.
Prof. Barrett explained that multifocal, trifocal and diffractive EDoFs often have negative side effects such as dysphotopsia, halos and glare.
Compared to other IOLs, the RayOne EMV toric lens offers several advantages: It provides better vision in low light conditions, reduces glare and halos, and improves contrast sensitivity.
RayOne EMV is a truly non-diffractive IOL that does not use light splitting technology like many IOLs that increase depth of focus, resulting in low levels of dysphotopsia, similar to standard monofocal lenses.
The art of designing optics
During the session at APACRS 2023, Prof. Barrett said that he designed the monovision EMV to be used with a monovision approach.
He and other surgeons have used a monovision approach for years with conventional monofocal IOLs, but now with EMV, the monovision approach is enhanced and true blended vision is acquired.
A keen astronomer in his spare time, Prof. Barrett explained to the audience that using a telescope requires perfect quality.
“You can tell the quality of a telescope by moving the focus in and out while you focus on a single stone. 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.
“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 RayOne EMV work?
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 into intermediate with up to 1.5 D of depth of focus (per lens on the spectacle plane).
Most patients implanted bilaterally with a new non-diffractive enhanced monofocal intraocular lens targeting micro monovision ended up with good distance and intermediate vision, and many achieved spectacle independence.
The RayOne EMV provides up to 1.5 D increased range of focus with an emmetropic target, yet with low levels of contrast sensitivity and dysphotopsia similar to standard monofocal lenses.
It is designed to provide a smoother, blended transition between the eyes when compared to monovision with standard monofocals, 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.
He said that while some patients face issues such as dysphotopsias and night vision concerns with other IOLs, he recommends using the RayOne EMV.
“I started out using refractive 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.
While each patient’s needs are unique and need to be assessed before selecting an IOL, overall, the RayOne EMV toric lens is an excellent choice for patients with cataracts, providing clear and improved visual outcomes.
Editor’s Note: A version of this article was first published in CAKE POST (APACRS 2023 Edition), Issue 3.
