Unequal presbyopia?

I measured near 6 cm for left eye and 7 cm for right eye without lenses, and the far power is about 1.5 D (67 cm). This means my power of accommodation is about 15.2 D left eye and 12.8 D right eye (16.7 - 1.5 = 15.2, 14.3 - 1.5 = 12.8).

It could be measurement error, but is the 2.4 D difference in each eye a potential issue in the future? Also, it seemed to drop from about 23 D when I was 19 years old (6 years ago), so does the rapid drop mean that presbyopia is a big concern for me, even though the number still seems to be above average for a 25-year-old? Or is it just a normal rapid drop in charts like Figure 1 of this article?

I measure presbyopia using this technique:

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I’m jealous that you have so much amplitude of accommodation!

In general the crystalline lens stiffens and becomes less elastic as you age. I don’t think the difference in accommodation amplitude between your eyes is a big deal. If you want to (you don’t have to) you can train your accommodation using lens flippers.

You can also print out a Hart chart and do “accommodative rock”. You can also do it without any special tools, just get a book or magazine, and an eye chart on the wall, and switch back and forth. Read a line of the magazine, then read wall chart, etc.

There is also a drug in development now that may soften the lens and restore its elasticity, probably hitting the market in 2024.

https://www.nature.com/articles/s41433-020-01391-z

Other than it sucks getting old for everyone, I don’t think you have anything to worry about. I’d do all the EM stuff to preserve your eyes, watch out for smartphones and excessive near work.

My measurement is basically Donder’s push up method. This article (Accommodative Amplitude Determination: Pull-away versus Push-up Method) specifically used the same technique and measured the average amplitude of accommodation in diopters as 16.5, 13.2, and 11.1 for age ranges 7-12, 13-21, and 21-35.

I have more pressing issues to deal with at the moment, but I will have to watch out for presbyopia in the future.

This is probably better than using lens flippers (the video uses the lens flipper to check accommodative facility, which is ability to change accommodation quickly while maintaining fixed convergence). Shifting between real near/far objects will change convergence. I would also expect looking at something 10 cm away and then something far away is easier than looking at something far away and flipping -10 and 0 lenses or something at 40 cm and flipping +2.5 and -7.5 lenses.