As he approaches the end of his epic ophthalmic journey of retinopexy, cryopexy, vitrectomy and IOL surgery, Professor Nathan Efron rues the fact that he is still partially dependent
on glasses.
Forty-seven years. That’s a big chunk out of anyone’s life. Forty-seven years. For me, it is the number of consecutive years of my life, from age 14 to 61, that I have had to either balance a pair of glasses on my face, or insert contact lenses into my eyes. Forty-seven years.
As challenging as my ophthalmic journey has been, there was always the light at the end of the tunnel of being free from glasses or contact lenses. In fact, it was this tantalising prospect that tipped the balance in favour of going ahead with my vitrectomy procedures in the first place. Getting rid of those horribly annoying floaters was one thing, but ending up with a pair of ‘designer monovision eyes’ – one eye corrected for distance and one for near – and ending up being free of glasses, was equally motivating.
Disappointingly, it hasn’t ended up like that. Rather than rejoicing at being free from optical aids, I now have seven pairs of glasses! Now that might sound like a bit of an over-kill, and I suppose it is. As is the case with all ophthalmic practitioners, being ‘in the trade’, and having private health insurance, gives me access to reduced-cost or no-cost eye wear and accords me the luxury of adopting multiple and sometimes redundant optical solutions.
Rather than rejoicing at being free from optical aids, I now have seven pairs of glasses
So let me explain how and why I have ended up with seven pairs of glasses. They are individually numbered in Figure 1, and throughout this blog I shall refer to each pair of glasses by the corresponding number in square brackets.
Rationale for my Vast Collection
Let’s start with my refraction, which has ended up as R -1.25/-1.00 x 75 L +0.25/-0.50 x 45. For all intents and purposes, my left eye is perfectly emmetropic. This gives me beautiful, crisp vision for distance. Absolutely no complaints there!
However, my right ‘reading eye’ is the problem; although it has the intended best sphere correction of -1.75D, my right eye is encumbered with a pesky 1.00D of astigmatism. Furthermore, my vision in this eye is plagued by a small paramacular blind spot, to which I have been referring throughout this series as my ‘flying angel of death’. While I can sort of read my iPhone and text on my computer screen, near vision out of my right eye is not clear and is much sharper when corrected. It is sharper still when I am binocularly corrected.
My favourite pair of glasses [1] are my look-overs. These have a +2.00 add over the distance prescription. An important part of my work is attending meetings of various kinds – from small group chats with my research team at QUT, to larger boards and committees within and outside the university. More often than not I chair these meetings. As Chair, I like to eyeball my colleagues while matters are being discussed, and I much prefer to do this directly, without looking through a lens or having my eyes circumscribed by a spectacle frame. Interestingly, I found it hard sourcing a look-over frame; they seem to have gone out of fashion.
I tried wearing varifocal lenses [2], but these were a complete disaster, and perhaps I should have anticipated the problem. The idea of varifocals was to afford sharp distance vision for critical viewing, such as at the football or attending a concert or live theatre, as well as good close vision to read the program. Although distance vision with varifocals was good when looking directly ahead through the ‘sweet spot’ of the lens, any eye excursion away from the lens centre resulted in significantly degraded vision.
Now, I had worn varifocal lenses successfully in the past for correcting my 7.00D or thereabouts of myopic astigmatism. The big difference between that experience and now is that, with a high prescription, although off-axis viewing is slightly degraded, it is still far superior than being uncorrected. In that scenario, the off-axis optical degradation was unnoticeable.
With my low prescription, the off-axis aberrations outside of the small non-aberrated optics of the distance portion of the varifocal lenses resulted in vision that was worse than no lenses at all!
After persisting with this for a couple of weeks I gave up, and had the lenses in these frames changed to D-seg bifocals, which work well.
As an enthusiastic spectator of sports, critically sharp distance vision is important for me. Although I am very happy with the uncorrected distance vision of 6/4 in my left eye, things look even sharper with both eyes corrected, presumably because our brain is more comfortable with a binocular lock. So, for full-field sports spectating without the restriction of an inferior bifocal segment, I also have a pair of single vision distance glasses [3].
Chained to the Computer
As an academic and author of scientific papers, books, articles and blogs, probably 80 per cent of my typical working day is at the computer, so a good optical solution for computer work is an absolute requirement. I therefore designed myself a special pair of computing glasses [4], which are D-seg bifocals with an intermediate correction (+1.75D) in the top half and an extra add of +0.75D in the near D-segment.
The extra +0.75D add, which results in a near correction of +2.50D in the D-seg, is useful when someone hands me some printed material, or I need to consult a textbook, printed journal article or indeed any document with small print, or to sign papers etc. I found this optical solution so useful that I had a duplicate pair made up [5] – one for the office at QUT and one for my home office.
Now a Sunglasses Addict
When I started going on my long beach walks following my first intra-ocular lens (IOL) replacement operation in my right eye, I found bright light a bit difficult to tolerate and started to wear plano ‘off the shelf’ sunglasses. Following my left eye IOL replacement, the sun glare was even more intense and I needed a good optical solution for this.
I had always worn contact lenses with UV blockers, which provided triple protection against developing pterygium, accelerated crystalline lens yellowing and retinal damage. My new IOLs have a UV blocker, so my retina is still protected. However, without contact lenses, I am at increased risk of developing pterygium. So, wearing sunglasses outdoors would serve three purposes: reducing the strong glare due to more light entering my eye in the absence of yellowing crystalline lenses, minimising my risk of developing pterygium, and sharpening vision via a full binocular optical correction.
I had a nice pair of brown polaroid single vision lenses made up in a designer frame [6]. They are fantastic: great sun glare protection with the polaroid lenses working to great effect on the beach front, enhancing the visual aesthetics of the sun, sea, surf, sand and sky. However, it occurred to me that a near add could be useful… but it is here that I made a costly mistake.
Since I already had brown polaroid sunglasses, I decided to opt for blue polaroid varifocal lenses in a stylish wrap-around frame [7]. Unfortunately, I did this at the same time as ordering my clear varifocal glasses, which as I explained above, ended up being a disaster due to degraded off-axis distance vision. Well, unsurprisingly, the same happened with the varifocal sunglasses, but the problem was exacerbated by the highly curved ‘wrap around’ lens form. I persisted for three weeks with these sunglasses, but found the off-axis visual degradation very disorienting, and eventually gave up and replaced the varifocal lenses with single vision lenses.
Interestingly, I had hardly ever worn sunglasses until now. I never felt I needed then for sun glare protection, or as a fashion accessory. Now I am addicted to them. I wondered, however, if I would ever ‘adapt’ to all this sun glare I was now noticing with my pseudophakic eyes. I put this question to my good friend Professor James Wolffsohn from Aston University in the UK, who happened to be visiting me on the Gold Coast.
Over the past decade, James has conducted extensive research on vision following cataract surgery. He told me that patients generally report that sun glare is especially problematic for the first two or three months following cataract surgery, but they eventually ‘adapt’ after that. Whether this is true physiological adaptation, or just psychologically ‘getting used to it’, is unclear.
I told James that the same seemed to happen to me. After a few months, the glare didn’t seem to bother me as much. Nevertheless, sunglasses still do make a difference both in terms of reducing sun glare and enhancing vision. Indeed, I feel totally relaxed and comfortable wearing sunglasses outdoors – especially at the beach and when driving – so I think sunglasses are going to be a constant feature of my new image from now on.
Professor Nathan Efron AC is a researcher at the Institute of Health and Biomedical Innovation and School of Optometry and Vision Science, Queensland University of Technology. He is currently president of the Australian College of Optometry and vice-president of the International Society for Contact Lens Research.