If you are like I was as a new graduate optometrist, progressive lenses were a foreign concept. We were all taught how they work, and we all became experts at drawing the hourglass shape and explaining the different zones. However, one thing new graduates in particular are not taught much about, is the science behind progressive lenses and understanding different lens designs.
By understanding lens designs, we can better recommend specific lens types to meet and exceed patient demands. When I became a practice owner, knowledge of progressive lens options and technology was the first I sought to gain.
I had so many questions:
- Why do some patients struggle to adapt to progressive lenses?
- Why do some patients report difficulties at certain working distances?
- What lens options should I be prescribing?
- How do I explain to patients how different designs work?
- How do I ensure my patients are being optimally fit?
After many years of private practice ownership, including fitting, dispensing, and prescribing progressive lenses to my patients, I have acquired the knowledge to answer many of these common concerns.
In my practice, I heavily rely on Varilux® lenses. Varilux lenses are made possible through Essilor’s unique approach to R&D- called “LiveOptics.” This design process uses a combination of digital prototyping, wave front analysis, and clinical trials to ensure theoretical design provides measurable visual improvements for the wearer.
Before we understand what makes Varilux lenses different from other progressive lens options on the market, we need to examine some of the most common challenges associated with wearing progressive lenses.
The Challenges Patients Face When Wearing Progressive Lenses
A progressive lens is one that allows a seamless transition from distance, to intermediate, to near viewing. As we all know, progressives are unlike traditional bifocals in that they offer this intermediate viewing zone.
In my clinical experience, some barriers to patient adaptation included complaints of:
- “Swim” – or when things seem distorted and blurry when making head movements
- Difficulties transitioning from distance to reading, across the intermediate zone
- Poor vision in dim lighting
The Solution: Varilux Lenses
Varilux lenses were the very first progressive lenses.
They were invented in 1959 by engineer Bernard Maitenaz who was not happy with the vision through his father’s traditional bifocal lenses. Since then, Essilor has worked tirelessly, leading the way in research and development to create lenses and utilize technology to provide the clearest, most comfortable vision for our patients.
The Varilux Portfolio of Lenses
There are several Varilux lenses offered in the portfolio including:
1) Varilux® X Series™ Lenses
Historically progressive lenses have only allowed wearers to see at any one distance throughout each specific point in the lens. Modern day presbyopes spend a lot of time working and engaging in tasks within arm’s reach. Older technology oftentimes required patients to move their head around to see optimally. Simply put, modern lifestyles have led to frustrated patients who struggle to find ”just the right spot” for specific viewing tasks.
New Varilux X Series lenses are designed with Xtend™ Technology, which allows the patient to see multiple distances through each point in the lens, extending wearers’ vision within arm’s reach so they no longer have to search for “just the right spot” to see sharply at any distance. This allows for significantly improved vision and comfort at distances within arm’s reach, a critical working zone for most patients.
Varilux X Series lenses are the result of immersing patients in research, testing and measurement from start to finish. Perfected through five years of research and 19 wearer studies with over 2,700 wearers, this lens is so advanced it has 15 new patents pending.
Varilux X Series also contains all of the technologies that made other Varilux lenses so successful:
- W.A.V.E. Technology 2™
Provides sharper vision at all distances, even in low light, by reducing the higher order aberrations found in all progressive lenses.
- SynchronEyes™ Technology
Provides smoother transitions between distance and near zones by calculating the lenses as a matched pair to promote improved binocularity.
- Nanoptix™ Technology
Reduces the “off-balance feeling” common to progressive lenses by controlling magnification between visual zones.
The new Varilux X Series lens are also part of Essilor’s new Ultimate Lens Package for progressive wearers that also includes new Crizal Sapphire® 360o UV lenses and Transitions® Signature® VII lenses for a complete solution in a single lens.
2) Varilux® Physio® W3+ Progressive Lenses
Poor vision in low light is a common occurrence in older progressive lens designs because the pupil naturally dilates in dark conditions. A dilated pupil can cause increased scattering of the light and aberrations when the light enters the eye through the lens.4
To combat this phenomenon, Essilor developed technology to predict how changes in pupil size would affect quality of vision.4
Stemming from this was their patented W.A.V.E. Technology 2: Wavefront Advanced Vision EnhancementTM, which corrects lens aberrations to optimize optical quality and deliver sharp vision in low light conditions.
Varilux Physio W3+ lenses also feature Binocular Booster technology that enables the eyes to work better together as a team. Booster Technology utilizes the prescription data in each eye and calculates a prescription as a pair to allow your eyes to work together more seamlessly.
3) Varilux Comfort® W2+ Progressive Lenses
Varilux Comfort W2+ progressive lenses work to allow for
- Better transition and access to near vision
- Widened distance and near zones for increased visual comfort
- Reduced peripheral blur and increased adaptation
Varilux Comfort progressive lenses also feature W.A.V.E. Technology 2: Wavefront Advanced Vision Enhancement™.
A large part of the success of these lenses is that they allow the user’s eyes to traverse the different lens zones quickly without compromise in vision, which is vital for patients working in visually stimulating environments with multiple devices and/or screens.
Which Varilux Lens Technology is Best for Your Patients?
Patients love the latest in technology whether in their cellphones or progressive lenses. I educate my patients on the many progressive lens options on the market and how what I offer is different.
Many patients report having to turn their heads too much when they look over their shoulders when driving, or having to constantly adjust their chin position on the computer. The goal of a quality progressive lens is for the patient to just put them on and go. Vision should feel real world, not like they are behind lenses. Varilux lenses make this possible.
Tips for Successfully Fitting Progressive Lenses
- Always prescribe the best design technology for your patient’s needs. If a manufacturer is making performance-based claims, ask to see data to back up the claims.
- In the past, it was recommended to drop segment heights by a couple millimeters from the pupil; however, a well-designed progressive lens should provide its best performance when fit to pupil center. If a progressive lens does not perform well when fit to pupil center, consider finding another design!
- Always measure from pupil center to the deepest point of the frame- even if that point is not directly below the pupil. For zyl frames, remember to add some height to account for the bevel.
- Frame selection is still imperative. Always ensure the frame shape will not cut off the reading zone (even if you have satisfied the minimum recommended fitting height, if the nasal portion of the frame sweeps up, you may be cutting off the near zone).
- Most modern designs have progression lengths which automatically vary to provide maximum performance over a range of fitting heights. A practitioner should very rarely need to specify a progression length (again, if a PAL does not perform well in “automatic mode,” consider finding another progressive). For rare instances where progression length must be specified, stay within 8mm and 11mm (<8mm compromises intermediate performance, >11mm compromises near).
- Patient education is vital. Explain the technology behind whatever brand of lens you recommend versus lenses they may find cheaper elsewhere. Patients need to understand the quality difference in what they are getting at your office.
- Bullimore, Mark A., PhD, and Kirk L. Smick, OD. “The Varilux S SeriesTM: SynchronEyes TechnologyTM — A Powerful, Innovative Approach to Binocular in Progressive Addition Lenses.” (2012): Print.
- “The Varilux S SeriesTM: Nanoptix TechnologyTM — A Revolutionary Approach to Fundamental Progressive Addition Lens Structure.” (2012): Print.
- Rice ML, Leske DA, Smestad CE, Holmes JM. “Results of ocular dominance testing depend on assessment method.” J AAPOS. 2008 Aug;12(4):365-9.
- James D. Colgain, OD. Varilux Physio EnhancedTM The First Progressive Lens Design to Use Pupil Size Modeling to Improve Vision in Low Light Conditions” (2010): Print.