Designing for presbyopes

Artificial intelligence design

EssilorLuxottica launched its Varilux XR series lens in 2023 to meet the needs of presbyopes, with a design that utilises behavioural artificial intelligence (AI) to “respect the natural behaviour of the eye.”

Alan Pitcher, commercial director for wholesale lenses at EssilorLuxottica, explained that through AI digital twin technology, “we were able to study patient’s visual behaviour."

By modelling object positions and visual behaviour in a 3D environment, Pitcher said, “it is possible to define the exact object positions relative to each wearer’s head, according to their behaviour.”

Meena Paur, global medical advisor at EssilorLuxottica, added: “If we know the wearer’s posture and behaviour while reading, it is possible to personalise the design of the progressive lens in accordance with the wearers needs.”

Near Vision Behaviour personalisation can be integrated into the lens for further tailoring.

Pitcher suggested: “Designing a lens that meets the changing needs of this growing cohort of patients means that practices have the best visual solution available to recommend to them at that time.”

“Patients are looking for a solution that can accommodate their visual needs and lifestyle but at the same time provide effortless vision, regardless of the viewing distance. For a practice, this demonstrates they have the latest solutions available to offer their patients and differentiates them from others,” he said.

Designing for astigmats

Rakhee Thakrar, senior professional affairs associate Vision Care, UK and Ireland, highlighted that contact lens wear declines markedly from 45 years of age according to the Vision Needs Monitor (2013).

Discomfort along with poor vision are the main reasons that one in three contact lens wearers over the age of 40 drop out of contact lens wear, she added, pointing to research by Rueff, E.M. and Bailey MD.  

Astigmats make up a large proportion of emerging presbyopes, the Bausch + Lomb team suggested, referencing a paper by Luensmann, D. et al. on ‘Spectacle prescriptions review to determine prevalence of Ametropia and coverage of frequent replacement soft toric contact lenses’ in Contact Lens and Anterior Eye. 

“Presbyopic astigmatic patients are interested in contact lenses just like other presbyopes. Historically, there have not been many readily available soft contact lens options to select from,” Thakrar shared.

“Presbyopic astigmatic patients who only wear spectacles are more likely than other spectacle-only wearers to perceive barriers to contact lens wear, less likely to be aware of multifocal contact lens options, and furthermore, are less likely to report having been recommended a multifocal contact lens by their eye care practitioner.”

To address the needs of this cohort of patients, the company introduced the Bausch + Lomb Ultra Multifocal for Astigmatism. The range has been expanded to 3280 parameters.

“The lens incorporates an advanced lens design, combining the revolutionary comfort of MoistureSeal Technology, the stabilisation geometry of OpticAlign Design and proven 3-Zone Progressive Design for stable, seamless vision at all distances.”

The lenses require two spectacle add powers across the range and feature a 3-Zone Progressive Design for clear vision and transitions across distances.

Discussing the design of the lens, Thakrar shared: “Bausch + Lomb researchers integrated a broader investigational approach and took seven key biometric variables into account, including: refractive error, pupil size, higher order aberrations, corneal curvature, axial length, anterior chamber depth and residual accommodation measured across nine viewing distances ranging between 25cm and 6m.”

The lens also combines the material Samfilcon A, made incorporating the MoistureSeal Technology.

To aid with fitting, Thakrar pointed to the Bausch + Lomb FitBetter app, available through Google Play or the App Store, allowing eye care practitioners to make a lens choice from the company’s entire range based upon the prescription.

“The tool allows us to put a fitting guide in to the hand of every eye care practitioner, giving them access to the fantastic offering of products that Bausch + Lomb can bring to their patients,” she said.

Going virtual

Jai Kudo Lenses, part of the Millmead Optical Group, introduced the Kudos system which utilises virtual reality (VR) technology to create a bespoke lens based on gaze dynamics, and which also offers a programme designed to educate presbyopes on varifocal lenses.

James Conway, CEO of Jai Kudo Lenses, told OT: “Using VR, we are able to capture each individual’s eye movements and use this heat map data to create a progressive lens design for each individual.”

Emphasising that there is no base design for the lens, Conway added: “Each lens design is completely unique and tailored to how each individual uses their eyes. We are using cutting-edge technology to take lens dispensing to new heights in every way.”

Patients are guided through a VR experience with the use of a headset that then captures points and directions of gaze. The data is then analysed into frequency of use maps for near, intermediate and distance visual ranges. A 19-digit code is created and sent to the Jai Kudo Lenses lab to create the lens.

This approach aims to minimise oblique astigmatism, provide a wider range of natural vision, and reduce potential adaptation issues.

The system also features Kudos Coach, a VR simulation that takes patients through an educational experience of using progressive lenses, breaking down misconceptions around varifocals.

Speaking to OT at the UK launch of the device, Conway suggested that Kudos could provide differentiation to independent practices.