EDOF in the Light Adjustable Lens and Loss of Contrast Sensitivity

Eye care
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This study put light adjustable lenses in both eyes of a group of patients, adjusting the dominant eye for emmetropia with no extension of the depth of focus and adjusting the non-dominant eye to have extended depth of focus (EDOF) by adding a predetermined amount of negative spherical aberration.

How much EDOF? A lot. 20/20 at distance and intermediate (24 inches) and 20/20 to 20/25 at near (16 inches). Acuity was actually reported in decimal form, but I translated it. They said 1.0 and 0.8 but I translated that to 20/20 and 20/25 .

The goal of the study was to explore the loss of contrast sensitivity due to the spherical aberrations. Result: The EDOF eye had lower contrast sensitivity than the other eye, but binocular contrast sensitivity was normal, even in the presence of glare.

This answers a lot of questions that have come up in recent discussions:
It tells us how much EDOF can be added to the LAL and how they do it.
It tells us the penalty for adding EDOF is not loss of peak acuity, but rather loss of contrast sensitivity.
And it tells us that having good contrast sensitivity in one eye in some sense makes up for lesser contrast sensitivity in the other.

[https://iovs.arvojournals.org/article.aspx?articleid=2331048]

" Contrast sensitivity in patients with aspheric profiles in light-adjustable intraocular lenses"

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Thanks. I was surprised to see the article is from 2015.

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“…adjusting the non-dominant eye to have extended depth of focus (EDOF) by adding a predetermined amount of negative spherical aberration.”

Seems to bias the EDOF CS sensitivity outcome when the spherical aberration always goes into the non-dominant eye of all 20 subjects, assumes eye dominance isn’t an important factor. I suppose that was done with the ethical limitation of research using human subjects.