First study I'd seen on effects of defocus in the elderly

Conclusions : In presbyopic subjects, imposed myopic retinal defocus caused thickening of SFCT, while hyperopic defocus caused thinning of SFCT. This implies that uncorrected presbyopia, which is associated with hyperopic retinal defocus for near objects and which is highly prevalent in the developing world, would likely be associated with choroidal thinning and possibly reduced choroidal blood flow with prolonged periods in a near visual environment.

This is what every optician needs to see…

To elaborate: giving people reading/computer glasses may provide health benefits to the eye independent of perfect refraction results.


Elderly? If around 55-60 is considered elderly, I will have to call myself ancient. I only had a quick look at this, the conclusions, and what conjectures we could draw from the conclusions. But since I read the study on how results in a experimental studies are not always repeatable in real life vision, I am hesitant about drawing too many conclusions from this.

What it seems to imply for presbyopes is that they are better off using their reading glasses.

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Compared to all the studies on five year olds and teenagers, we’re all elderly.

Presbyopia is a disease of aging, although it starts at midlife for those of us lucky to live in the modern age.

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It matches the studies done on teens, that defocus caused thickening choroidal tissue, but nobody’s done long term studies on if defocus improves retinal health. We have seen axial length measurements increase in our members in ranges that are consistent with thickening choroidal tissue, but we lack the numbers to say if this prevents retinal detachment down the road.


There is correlation here…

The average choroidal tissue thickness inversely correlates to the level of myopia.
The risk of many eye diseases correlates to the level of myopia.
Is it actual eyeball shape or is it the thin choroidal tissue that causes the elevated risk? Unproven.


I often encounter blue lighting like “clouds” in peripheral vision after myopic defocus.
But even AMD-like distortion near my blind spots seemed to reduce to a minimum after full correction / hyperopic defocus.

If you have pre-existing retinal damage, your visual cortex may not be able to keep up with the changes that come with thickening choroidal tissue.

Don’t confuse full correction of presbyopia (more plus) with full correction of myopia (more minus)

I don’t know whether I have retinal damage. Doctor said at the time of “ligthing” or “distortion” that my retina is OK, except some thinning at peripheral retina.

I don’t confuse, but this is not applicable to presbyopia then.
I wrote about myopic strain, so I get the opposite: myopic defocus seem to be more unhealthy on my retina.