PRODUCT PROFILE
EDOF: a new lens for presbyopia Presbyopia has been a current topic for years among eyecare academics, practitioners and contact lens manufacturers alike. Why? Studies estimate that 1.8 billion people worldwide will be presbyopic by 20501. But there are already about 340 million people over the age of 45 in need of some degree of correction for near vision in Europe alone1. However, as we all know and experience, instead of increasing sales, we tend to lose our patients when presbyopia comes. For most eyecare professionals, the problems associated with multifocal contact lenses are obvious: reduced contrast sensitivity, undesirable ghosting and diminished low contrast visual acuity2. Those issues are related to the centration, design and near add power of the contact lens – as well as to the patient’s spherical aberrations and pupil size2 (Figure 1). Even identifying all of this, we cannot stop dissatisfied patients from dropping out of the category. The limited choice of options with ‘off the shelf lenses’ means that we have limited options to modify the lens after we have chosen to fit it. At Mark’ennovy we have always believed that not every patient will be successful with mass produced lenses, even if they have a relatively straightforward correction. In our pursuit of excellence, we have teamed up with the Brien Holden Vision Institute (BHVI) to bring to market a new soft contact lens design specifically for presbyopia. This exciting technology is now available in the UK.
BESPOKE BENEFITS FOR PATIENTS EDOF is an individually crafted, monthly replacement, soft silicone hydrogel contact lens in Mark'ennovy's signature range of diameters and base curves. EDOF is powered by the BHVI’s patented extended depth of focus technology. Thanks to the optimisation of higher order aberrations, and having considered different pupil sizes and decentrations, EDOF provides clear vision at all distances, minimising unwelcome visual compromises like
Figure 1 Factors affecting multifocal contact lenses performance
Figure 2 Fictitious 2D and optical design for an EDOF contact lens for presbyopia
ghosting and haloes. This supports a comfortable adjustment to the lens, enhancing the overall wearing experience. The significant benefits of EDOF include: A fast and seamless transition between distances E DOF lenses were designed using deliberate manipulation of higher order aberrations to provide good vision at all viewing distances Removes soft focus T his optical design in conjunction with the optics of wearer’s eye provides an image on the retina of the corrected eye that remains above an acceptable retinal image quality threshold Minimises haloes and ghosting It is different in the way it has been calculated and optimised to make the performance stable over pupil changes, insensitive to centration, and independent of inherent ocular aberrations
Effective in all lighting conditions The optical power is distributed across the optical zone in such a way that it offers an extended depth of focus effect (Figure 2). This results in better visual perception for the patient in general So, why settle for ‘functional’ vision when patients can enjoy EDOF?
REFERENCES 1. Holden et al. Global vision impairment due to uncorrected presbyopia. American Journal of Ophthalmology 2008;126(12):1731-1739. 2. Bakaraj, RC et al. 2018. Extended depth of focus contact lenses vs. two commercial multifocals: Part 2. Visual performance after one week of lens wear. Journal of Optometry 2018;11(1):21-32.
NEG members interested in learning more about EDOF can contact their business development manager or our customer care team on 0800 328 0610. Alternatively, email mkservices@markennovy.com
Article supplied by Mark'ennovy UK. Vision Now December 2021 21
