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Tuesday / August 9.
HomemicontactWhoosh! There Goes the Year

Whoosh! There Goes the Year

Having explored the options for customised CL fitting, Alan Saks says the daily CLs we’re fitting now will be very hard to beat.

The year is flying by! Soon we’ll have knocked the first quarter of 2016 on its head. The usual rash of conferences, CPD events and launches will also be kicking in around now. They’ll keep us busy until October when everyone once again chills out and prepares for the festive season and holidays.

Of late I’ve read increasingly about a group of people who espouse a desired shift to customised, sag-based and eye surface profile related soft contact lens fitting. Frankly I think they’re dreaming.

Yes, it may be a more perfect approach but in real life and the real world we have to live with factors such as practicality, pragmatism and affordability.

…for now, be confident that the top of the range dailies that we’re fitting will be very hard to beat…

I see it as highly unlikely that we’ll be going back to customised soft lenses for individual eyes, as opposed to single use disposable lenses. For the vast majority of patients, single use lenses provide superb results. The latest generations of dailies provide excellent comfort and fitting, with adequate movement, wettable, lubricious surfaces and great vision. The top range si-hy lenses also provide close to no-lens oxygen levels and easily exceed the Holden-Mertz transmissibility levels for oedema free daily wear (DW). Some of the highest Dk si-hy dailies provide around four to six times more oxygen transmissibility than the DW Holden-Mertz target, while some are almost double the extended wear criterion.

So how do the proponents of this customised sag and profile based CL fitting intend to achieve such a radical change in the contact lens supply chain?

The only way I see this happening is to implement the strategy I‘ve suggested in the past, in my idealistic crystal-ball view of the CL world future. In a nutshell, what I’ve proposed in the past would be to obtain aberrometry and refraction details for each patient. This is already achievable and some people are already doing this routinely. We can also now obtain an eye surface profile to control the fit and determine the shape beyond the peripheral cornea, as well as the topography of the cornea. We could then send all this information down a fibre optic line to a local, daily disposable manufacturing facility in each major city. Such a production facility could be fitted into a shipping container. We could then spit out a year’s supply of customised daily disposables. They’d be shaped and sized to each individual eye profile and include optimised aberration controlled optics to give that specific patient the best possible comfort and visual quality.

I do, however, suspect that’s a way off yet… I wonder if CL manufacturers will ever embark on such a project?

Anything’s Possible

Having seen Menicon’s custom spin-casting disposable facility in Singapore it’s certainly possible: Custom designed by the legendary Aussie Steve Newman, his compact manufacturing line for disposables (including spin-casting, curing, quality control and packaging) fits into a space way smaller than a shipping container. It’s what the Miro lens is made on, with superb repeatability and quality. It would be ideally suited to my aforementioned proposal.

No doubt time will tell but, for now, be confident that the top of the range dailies that we’re fitting will be very hard to beat from a cost-per-lens and results point of view.

Another thing that idealists don’t always seem to get is that if we fit a hard lens or soft lens to exactly follow the cornea’s curves we will end up with a lens that is very tight peripherally or gets bound with little or no movement, or tear exchange. A lens does have to ‘land’ somewhere. People who’ve tried this theoretically ideal approach have found this out and have had to compromise and land the lens someplace on the cornea, limbus or sclera.

What they also don’t seem to realise is that we have in fact been making custom fitted soft CLs for decades. In fact I cut my teeth fitting soft lenses in steps of 0.05mm in base curve and diameters in 0.25mm steps. We still do for patients that are out of range of disposables in terms of sphere, cyl, axis, diameter and base curve. So it’s not rocket science and the only real benefits would be a slightly more precise ‘fit’ and aberration controlled optics. Again, however, lenses that would correct higher order aberrations would need to be ‘point to point’ specific and thus rotationally-stable. They’d thus need some form of advanced stabilisation design or prism-ballast, which may be counter to the intended ideal shape, aberration-control or best comfort!

Online

As of 2016, two of the top-rated optometric journals, Clinical and Experimental Optometry (CXO) and Optometry and Vision Science (OVS), are now online only.

Although it’s nice to have a high quality printed journal to read, the online only option makes sense, for such clinical and academic journals. Many prefer to download PDFs of relevant papers and save them to reference managers such as the Papers App: A powerful virtual library that helps with citing, sharing, search, referencing and more.

Online versions also allow for high-quality colour images and better graphs/tables, which can be zoomed for ease of viewing. We’ll also likely see more videos and other interactive content. One can save images and download PowerPoint slides for use in lectures and so on. Many trees will be saved and the carbon-footprint greatly reduced.

Having been involved in publishing since the 1970s – when cut and paste was done with scissors and glue – I retain an enduring love for print, as do many others.

mivision and other magazines with broader scope than the rather dry academic journals, incorporate so much more. They are rich and varied with diverse content and imagery, covering business, fashion, technology, news, people, eyecare and eyewear, to mention just a few.

The design, typography and images are to be enjoyed. One can flip between pages and gain a ‘photo memory’ of something that caught your eye. Days, months or even years later one can pick up a book or magazine and know that a few pages from the back, on the left inside page, you can find what you wanted. I see print and online as synergistic.

I expect British journals like Contact Lens and Interior Eye and Ophthalmic and Physiological Optics will probably remain in print as well as online for some time as the UK can be seen as one of the hearts of printing and academic journals.

For online-only academic publications the cost of subscribing should be significantly reduced, especially for overseas subscribers, but I doubt we’ll see that filter through. One of the other major benefits of this swing to online-only is that the publishers of OVS have now digitised every issue, going back almost a century, to 1926. These editions are thus now available for us nerds to read and review. In its early days OVS was known as the American Journal of Optometry and later on as the American Journal of Optometry and Physiological Optics. The journal was pretty heavy duty. It had a garish yellow cover and we fondly referred to it as the ‘yellow peril’, as it was at times quite daunting to read.

I’ve been enjoying access to some papers from my student days in the late 1970s. I’ve also been able to access, among many others, some Hill and Fatt papers from the 1960s, as part of some research I’ve been doing for an article to be published next month.

Check them out through your subscriptions, institutional access or via open access on the publishers’ website.
It seems to me that most of the archives from 1926 to recent years are now free and open access, which is fantastic.

In time it would be nice to see all archives and past editions of all journals become free and open access, as there are some amazing papers out there.

The future is now, as is the past.

Alan P Saks MCOptom(UK) Dip.Optom(ZA)
FCLS(NZ) FAAO(USA) is a third generation optometrist based in Auckland, New Zealand and columnist for mivsion. He is actively involved in the profession, having served multiple terms as president of Contact Lens Societies and arranged numerous conferences. He has also served on education committees, as examiner in contact lenses and clinical optometry examinations, lectured contact lenses to ophthalmology registrars and written several columns about eye health and the practice of optometry.

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