Building lifestyle into the lens
As changing patient lifestyles drive suppliers to source new solutions, OT takes a look at the technology behind three lens solutions meeting the needs of growing patient groups
Patient requirements are at the heart of product innovations across optics and eyewear, and key groups and evolving needs are emerging as important areas of focus for manufacturers seeking to support practices and reach patients with their solutions.
Despite the disruption of the pandemic, innovation has not stopped. In fact, a survey by McKinsey & Company found that, across industries, only pharmaceuticals and medical had increased their focus on innovation during the COVID-19 crisis.
Recent months have seen Hoya introduce its Miyosmart lens for myopia management, with the anticipated rise in myopia over the next 30 years and Essilor its Varilux Comfort Max for the presbyopic market – providing tailored solutions for those key patient groups that are expected to continue growing.
Companies have also highlighted the impact that modern lifestyles are continuing to have on patients and the way spectacle wearers see through their lenses – a lifestyle shift that has only grown during the pandemic – and something Zeiss has explored in its SmartLife portfolio.
With these areas of patient need unlikely to abate any time soon, OT asked the three suppliers about these key areas of development and the technology behind their innovations.
The always-on lifestyle
A key shift that suppliers have noticed in patient behaviour has been the greater use of digital devices, particularly so during the pandemic, with the ever-connected lifestyle leading to changes in patient requirements.
Speaking to OT, Paul Hopkins, optometrist and professional services manager at Zeiss Vision UK and Ireland, shared: “The digital community is growing, and connectivity is increasing regardless of age. More than 50% of the world’s population now carries a portable digital device.”
“This connectivity means that we rarely switch off – neither our devices nor our minds,” Hopkins said, suggesting the same can be said for the eyes: “Over time, the constant need to multitask and change our viewing distances between devices, screens, another person or task means the way our eyes behave has also changed.”
The use of devices has increased over the pandemic, with Zeiss finding in a survey with OnePoll that 61% of respondents use a laptop and another digital device simultaneously, whilst 57% use a smartphone and another device simultaneously.
“Considering the recent changes in working habits due to the global pandemic, of those we surveyed, 60% agree that they multitask more when they’re working from home,” Hopkins noted. It would seem that the public has noticed this difference, with the survey finding that 42% think their eyes are having to multitask throughout the day by looking at screens, while 34% think their eyes have to multitask due to switching between different distances.
The survey also found that 26% of people experienced problems with clarity of vision when switching between different distances.
The company argued that this fast-paced lifestyle and constant connection – even while on the move – can lead to eye strain and the need for wider fields of view.
The change has also led to new patterns of body posture and eye movements, such as a downward-shifted gaze, using central and peripheral vision to navigate, and a downward eye rotation.
Illustrating this, a 2019 study by the Zeiss Vision Science Lab found that regular use of smartphones has led people to look down more than we used to, using more of the lens – particularly the lower part of the lens.
These changes in behaviour occur on top of the changing visual needs that patients already experience through ageing, the company shared, particularly the decrease in the amplitude of accommodation, and a decrease in pupil diameter.
Hopkins shared: “As we live in an ever more connected world, with a heavy reliance on digital devices, now more than ever patients need a lens that can keep up with their busy lifestyles.”
He added that the Zeiss SmartLife lens portfolio is designed to widen a patient’s clear field of view and cater for the changes in accommodation and pupil diameter that occur through ageing.
The lenses in the Zeiss SmartLife portfolio have been developed using Zeiss SmartView Technology, which comprises four “key pillars” including thin and light lenses, precision through the design process, and a consideration of how visual needs evolve, as well as the use of object-space-models and “design fingerprints” (distribution of vision zones) adapted to the visual behaviours of lens wearers.
The object-space-model is used to account for the dynamic visual behaviour of wearers, flattening the distribution of dioptric power in the lens periphery in order to create smoother vision. This is something the company found was needed for the frequent changes in head and eye posture that is observed in the way people interact with their devices.
In order to address the varying needs of the different age groups, the portfolio is made up of three different lens types, which the company suggests can assist wearers as they switch their attention from their devices to their environment.
Meeting the needs of presbyopes and pre-presbyopes
Presbyopia is a key area of focus for the industry, suggests Dr Andy Hepworth, professional relations manager for Essilor, highlighting: “Within the UK, we have an ageing population and figures highlight that in about 2025, a third of the population will be over 55.”
Office for National Statistics data from 2019 suggested one in five people were 65 years of age or older, with predictions that this will increase to one in four by 2050.
Hepworth suggests this shift could mean that multifocal spectacles – varifocals in particular – could become ever more dispensed to the wearer.
Last autumn, Essilor launched its Varilux Comfort Max, a new addition to its varifocal lenses, designed to offer wearers greater flexibility in the postures they can adopt whilst still being able to see sharply.
Launching the lens, Essilor explained that it was created specifically for wearers with busy lifestyles who take part in activities that result in static postures or cause prolonged strain on the eyes.
The lens was designed using Essilor’s Flex Optim technology to increase the ‘useful vision zone’ of the lens by up to 46%, enabling wearers to adopt a broader range of head movements which provides an increased level of comfort.
In particular, this expansion also enables the wearer to adopt up to 495 different body postures when looking at a computer or desktop screen.
Explaining the reason behind this, Hepworth highlighted the impact of increased connectivity on patient lifestyles, commenting that with people now needing to multitask more within the arm’s length area: “It has become quite clear to our research and development (R&D) team and market researchers that members of the public – presbyopic and pre-presbyopes – need correction that satisfies the use of digital devices.”
With the increasingly connected environment, Hepworth added that the company has also seen a need to provide additional support to pre-presbyopes, noting: “they are finding they need more visual support within this arms-length area.”
To address this particular need, the company has developed its Eyezen lenses, Hepworth explained “there is a huge help that advanced single vision lenses can bring to these pre-presbyopes.”
The single vision lenses are enhanced to meet the modern visual requirements of wearers, and “to support the visual effort required when using multiple screens,” Hepworth said.
Eyezen Boost lenses feature a power distribution technology, Eyezen Focus, which has been designed to provide a ‘boost’ in the bottom of the lens to support the eye’s accommodation effort when using digital devices. Similarly, Eyezen Start offers Eyezen Dualoptim Technology which takes into account the reference points of distance and near vision, with the lens surface optimised “according to object distance and gaze direction.”
This increased usage of digital devices across both presbyopes and pre-presbyopes has been of particular importance for lens development at the company.
In order to model how wearers behave in their spectacles, as well as the positions they adopt to interact with their environment and devices, Essilor’s R&D teams developed a new simulation process. The LiveOptics process utilises avatar simulations to mathematically model the conditions of an “infinite number of real-life vision tasks,” Hepworth said.
The technology was first touched on in the development of the Varilux X series in 2018, but was more robustly utilised within the framework of the Varilux Comfort Max, he explained.
Describing how the avatars are used to form a prototype ahead of live testing, Hepworth shared: “What these avatars do is tell us what needs to be built into a Varilux design. The R&D teams look at that information, add the features in and then can keep tweaking.”
Meanwhile, the technology can also help to inform future innovation. Hepworth told OT: “The R&D teams can continue using these avatars to try and work out what is going to be happening in the future, and what the Varilux lens needs to have the ability to do.”
Hepworth added that, using these technologies, the team will already be working on the next generation of the lens, and likely also working on the generations to come.
Innovating in myopia
On the other end of the spectrum, Hoya has also been working to meet the needs of a growing patient group with a focus on myopia management.
“Myopia is a significant global public health and socioeconomic problem and has been steadily increasing in recent decades,” Andy Sanders, professional services director at Hoya Lens UK, said.
The company has also seen a shift in patient behaviours due to modern lifestyles. Discussing how changes in patient requirements have led to the need for the technology, Sanders told OT: “When we consider the reasons behind the advancing growth of myopia, studies have shown that indoor lifestyles and the lack of outdoor activities in our digitally-led routines may be a driving factor.”
To address the issue of myopia progression in children, this year Hoya launched its MiyoSmart lens, featuring a patented technology called Defocus Incorporated Multiple Segments (DIMS). The approach utilises hundreds of small defocus islands to create a myopic defocus effect, which the company suggests helps to slow myopia progression and axial elongation in myopic children.
Describing how the concept began, Hoya told OT that Dr Chi-ho To, head of the school of optometry at the Hong Kong Polytechnic University and chair professor of experimental optometry, had been exploring resources which detailed current myopia control methods.
When on a bus, Dr To noticed the dark tinted windows had contra-vision type film which allowed those inside the bus to see out but not vice versa. Sanders explained: “Being a myopic patient himself, he removed his glasses to see through the little holes that the window film had, and to his surprise, he could see clearly with a very acceptable visual acuity.”
The professor reviewed optical alternatives that slow down the progression of myopia, finding nothing about optical defocus, Sanders shared, adding: “From his experience with the window film on the bus, and the findings from his recent literature review, he concluded that a way to control myopia could be in combining two stimuli, one with minus power and another one with plus power.”
Having reviewed data from a contact lens trial that involved simultaneous defocus, the professor worked on a model that would use a defocus incorporated multi-segment spectacle lens design to manage myopia progression.
“This would override the eye movement that we experience while we wear glasses (versus contact lenses), with a stable vision of near and distant vision with myopic defocus,” Sanders said.
Reflecting on what makes the Miyosmart unique, Sanders explained: “The key to the Miyosmart spectacle lens is the honeycomb treatment zone that gives simultaneous distance focus and myopia defocus, the eye experiences this in all directions of gaze.
“Previous lens designs relied on defocus created by an add in the lower part of the lens or a blended aspheric type concept where the periphery becomes more plus, consequently the simultaneous focus/defocus is not achieved.”
The Miyosmart lens hosts a clear central hexagonal area of 9.4mm diameter which provides the patient with the full myopia correction. This area is then surrounded by a treatment zone of 33m which consists of micro-lenslets, each with a +3.50D power and measuring 1.03mm in diameter, distributed exactly 1.5mm centre to centre.
Describing how this approach addresses myopia, Sanders explained: “Unlike standard spectacle lenses, which produce peripheral hypermetropic defocus on the retina, which is hypothesised to drive myopia progression, the Miyosmart lens creates peripheral myopic defocus reducing the progression trigger.”
Likened to a “honeycomb,” the structure of the defocus zone provides an average ratio of myopia correction to defocus of 50:50. Sanders highlighted: “When the patient looks directly through the defocus zone, visual acuity remains almost unchanged.”
While the lenslets have a power of +3.50, Sanders emphasised that this does not perform like a bifocal addition, sharing: “The technology is completely hidden – invisible to both wearer and observer.”
The company has plans to further build on the technology, Sanders confirmed, sharing: “Hoya is already investigating potential improvements and additional lens options to enhance its myopia management offering.”