In its ongoing commitment to improving standards and sharing new ideas, Contamac recently invited some of the leading minds in the speciality lens field to a couple of roundtable discussions on current challenges and future opportunities. It was a perfect opportunity for the award‐winning lens materials manufacturer to listen and to learn.
While the conversations proved as passionate, insightful – and often mischievous – as anyone could wish for, education inevitably provided a recurring theme.
Twenty-four experts from ten nations converged on Contamac’s UK headquarters for the two events. An unflinching appraisal of current lens materials gave Contamac the chance to take notes and share details of new products being developed in‐house, while the free‐flowing nature of both discussions also resulted in a thorough airing of everything from lens development to the prospect of automated contact lens fitting.
The discussions soon warm up when the subject of myopia control is raised. All agree that myopia control is going to be a major topic for years to come. Most optometry teaching and research bodies are actively researching the issue, and larger corporations are developing soft lens designs to meet expected demand. Yet, while the industry and professions recognise the phenomenon, and health authorities around the globe are waking-up to the long‐term implications of the effect on their populations and social care institutions, some regulatory authorities are still putting up barriers that will likely delay access to remedial devices for many progressing myopes. One notable exception is Russia, where Dr Myagkov reports that the Soviet health ministry has issued a directive to ophthalmologists, stating that they should actively pursue both ortho-k and soft multifocal remedies to arrest (or at least slow down) the progression of myopia in children.
As the information regarding the myopia epidemic filters down to the general public, demand for products to control myopic progression will increase. At the same time, results from numerous studies already underway around the globe should help in the refinement of both ortho-k and soft multifocal designs.
All our Key Opinion Leaders are actively involved in the fitting of scleral lenses, and so discussion on this one topic is inevitably involved – and lengthy! As they’ve become an essential part of the specialist fitter’s toolbox, so the design of scleral lenses has become more sophisticated over the past few years. Yet many of those present report that fogging is still an issue in the US – although it appears to be less so among European practitioners. Toric peripheries are now being used in the majority of fits, and fitting in closer proximity to the limbus appears to have helped with fogging issues. The more widespread use of OCT in scleral fitting has also improved accuracy.
Tangible Hydra-PEG surface coating has been of great benefit to many scleral wearers. But questions arise as to the durability of the coating, with some practitioners stating that patients are still deriving benefit up to 18 months later, while others report instances of lenses needing to be retreated after 6‐12 months. All agree that the way in which patients handle lenses and follow instructions is particularly important.
This in turn triggers a brief discussion regarding the benefits of using solutions other than normal unpreserved saline for the insertion of scleral lenses. Preserved saline contains none of the essential nutrients found in normal tears. Some speculate that an alternative could possibly be developed that would better aid the metabolism of the cornea for the often 12-plus hours that scleral lenses are on the eye. One European practitioner reports that he regularly uses such a solution, with beneficial results.
At the end of the discussion Langis Michaud points out that, “…for the regular cornea we have plenty of options other than silicone hydrogel. Anything gas permeable, especially in scleral lenses, will beat any kind of soft lens.” All agree that the growth in scleral lens fitting will continue.
According to Ed Bennett, the regular GP market has been somewhat ignored following the advent, and subsequent proliferation, of scleral lens fitting. César Lipener concurs, adding that the corneal GP is still his first choice of lens for most irregular corneas. Most practitioners agree that GPs remain a very viable option for presbyopia.
Hydrogels and Silicone Hydrogels
“Patients talk about comfort, while we talk about eye health,” says Chad Rosen. “Unless they have something wrong, like neovascularisation of the cornea, only then can we show them what’s wrong and why we want to change it”. Many speciality lens wearers continue to wear conventional hydrogel materials despite the added benefits of increased oxygen availability that silicone hydrogels bring. This may be due to the limited choice of silicone hydrogels available to speciality lens manufacturers. There’s also speculation that some current silicone hydrogel designs might be based on old original hydrogel material designs, and so don’t translate well to the different moduli and swell factors present in current silicone‐based materials.
As Greg DeNaeyer points out, “Dk isn’t everything. Handling, stability and comfort are key”. Most also agree that a monthly replacement speciality silicone hydrogel would be desirable, and that the benefits to the patient of such a lens would outweigh any slight reduction in Dk, provided it exceeded that of current hydrogels. A figure of 50Dk is suggested as being acceptable.
Parameter flexibility and choice are key. Many specialist labs offer the same diameters as moulded lenses, whereas Eef van der Worp says that 20‐25% of patients could benefit from a lens with a customised diameter and base curve.
As mentioned earlier, the consensus is that GPs offer better visual results than soft lenses. Many moulded lenses are available in only spherical form. The reduction in clarity caused by uncorrected astigmatism, plus the poorer image quality associated with a softer material, conspire to produce an overall reduction in acuity. Success then depends on how much of a reduction in acuity the patient is prepared to tolerate.
With an ageing population, the growth in interest in this modality can only increase. Custom soft designs with astigmatic correction and variable centre zone sizes may fulfil a need not met by moulded lenses, but GP designs probably offer the best solution at present. Most emerging presbyopes will currently be using some form of soft lens, and practitioners will naturally assume that they wish to continue in that modality. If it were explained to them, however, that discomfort issues they may have experienced with the GP lenses of their youth are unlikely to be replicated in modern designs and materials, then perhaps the success rates for presbyopes will increase.
Several practitioners mention that they’ve had good results with scleral lens designs, and suggest that the availability of surface coating technology has been helpful for this group of patients also.
Most of those present have had some experience with hybrid lenses. The US practitioners’ experiences are limited to one brand, Synergeyes, whereas some of the European practitioners have used the Eyebrid as well. Most think the advent of the scleral market has overshadowed the need for hybrids and would only use one for replacement purposes. Many of the US practitioners like the idea of a customisable hybrid design, such as Eyebrid, but are limited to the fixed designs offered in their own market. Again, the availability of Hydra-PEG surface coating on this type of product has improved wearer experiences.
Lab consultants are the unsung heroes of the speciality contact lens industry. Their knowledge and experience are invaluable to fitters of all ages and backgrounds. When asked what makes them choose one particular laboratory over another, the relationship with their lab consultants is a key factor for all practitioners.
Dr Tom Arnold, Optometrist and Owner at Today’s Vision in Sugarland, TX.
Joe Barr, former Editor of Contact Lens Spectrum and now Professor emeritus at Ohio State University College of Optometry.
Dr Melissa Barnett, Principal Optometrist at UC Davis Eye Centre.
Dr Ed Bennett, Professor and Assistant Dean at University of Missouri‐St Louis.
Dr Jean Bennett, Optometrist at Bogey Hills Vision.
Dr Antonio Calossi, Optometrist and lecturer at the University of Florence.
Mark Darling, BSc Hons, MCOptom, Optometrist and Owner at Mark Darling Eyecare and Opticians.
Dr Greg DeNaeyer, Clinical Director at Arena Eye Surgeons.
Dr John Gelles, Director, Specialty Contact Lens Division, Cornea and Laser Eye Institute, and CLEI Center for Keratoconus, New Jersey.
Bill Harvey, Clinical Editor at Optician Journal.
Professor Christian Kempgens, Professor of Optometry and Lecturer at the Beuth Hochschule für Technik, Berlin.
Dr Jamie Kuhn, Associate Optometrist at Kokopelli Eye Institute.
Dr Matthew Lampa, Associate Professor at Pacific University College of Optometry (PUCO), Oregon.
Bo Lauenborg, CEO, Danish Contact Lens Institute.
Dr Karen Lee, Clinical Instructor and Director of PROSE clinic, UCSF Department of Ophthalmology, San Francisco.
Professor Langis Michaud, Professor at the University of Montreal, Senior Contact Lens Optometrist and Clinical Researcher, Montreal.
Dr César Lipener, MD, Clínica Dr César Lipener.
Dr Giancarlo Montano, Optometrist and Professor of clinical contact lens application at the University of Salento.
Alexander Myagkov, MD, Director of the Russian Academy of Optometry and Optics.
Dr Chad Rosen, Assistant Professor at the Michigan College of Optometry.
Dr Eef van der Worp, Eye Care Educator and Researcher at Maastricht University, the Netherlands.
Dr Maria Walker, Clinical Professor at the University of Houston College of Optometry.
Dr Stephanie Woo, Optometrist at Havasu Eye Center, and Vice-President of the Scleral Lens Education Society, Arizona.
Dr Michael Wyss, Optometrist and adjunct faculty member at the New England College of Optometry (USA), Hochschule Aalen (Germany), TVCI (Czech Republic) and FHNW Optometry (Switzerland).
Roger Zimmer, Executive Vice President and Publisher at PentaVision LLC, publishers of Contact Lens Spectrum.