Thoughts on refraction with phoropter before/after dilation, with added reference to RxLAL adjust.

I've always had my eyeglass prescriptions done by my ophthalmologist, with fully dilated eyes. Is that not usual?

An ophthalmologist doing any kind of eyeglass prescription is unusual. They are surgeons not opticians. When I go to my ophthalmologist any eye tests the tech might do before I see the doctor (line test, auto refractor) are done before any drops. And I can't see for s**t after I've been dilated so again doing a prescription under those conditions doesn't make sense to me. Unless I'm missing something or misunderstanding something.

I've been seeing the same doctor for over 30 years. While he does perform cataract surgery, much of his practice is general ophthalmology.

As one website says: "An ophthalmologist diagnoses and treats all eye diseases, performs eye surgery and prescribes and fits eyeglasses and contact lenses to correct vision problems."

Before and after I had cataract surgery, whenever I saw I my ophthalmologist, the techs did the refraction before they dilated my eyes.

I did read somewhere that with some older adults with small pupils, some ophthalmologists prefer to dilate the eyes before a refraction.

. And I can't see for s**t after I've been dilated so again doing a prescription under those conditions doesn't make sense to me. Unless I'm missing something or misunderstanding something.

Would it make more sense to get refracted thru a pinhole or a highly constricted iris? Of course not. If there is enough light, pretty much all eyes focus well. It makes the focus non-critical.

Dilated eyes would be the opposite of a pinhole. It will make the refraction more critical.

Are you with me on any of that?

In cameras before the automatic sort, you could focus a lens, and you could open or tighten the iris. The iris controls the aperture. If you open the iris to its maximum, you can more readily adjust the focus. If you tighten (stop down) the iris, depth of field increases, and it is harder to chose the best focus.

An eye and a camera have some similarities.

I presume the lighting would be set lower if refracting dilated eyes.

Yes - mine are always done in a darkened room. And FWIW, all my eyeglass prescriptions have provided excellent vision, which is also due, I believe, to the fact that I use an independent optician who has his own lens grinding facility.

Is your thought - using 2 refractions, 1st not dilated and 2nd dilated, before a LAL adjustment will have more exacting results? Technically, should the 2 refractions be the same?

I can offer a theory as to why refraction before dilation is common. Many eye exams are not going to need dilation. So to refract before dilation makes the setup and procedures more consistent from patient to patient--- not needing a change in setup/procedure.

Have you changed your view at all, perhaps "might make some sense"? Responding to lighting changes during an eye exam is not common I think, except when they put that near Jaeger card up. They light that thing pretty brightly.

Got one RxLAL so far with the far eye. Good results, but about -1/4 D residual astigmatism. Much better than could be expected with conventional IOL. Still deciding what to do for the near eye, but it probably still be another LAL. But for a near eye, some kind of multi-focal or EDOF is still under consideration, and the non-operated eye has a milder cataract. I wear no glasses for driving, but readers for closer reading. Even in a dim restaurant for the menu.

The thought that doing the refraction while dilated, vs before being dilated anyway, was more thinking that at the time, before adjustments were made. To me, logic calls for refraction after dilation, and refraction then dilation makes less sense.

"Still deciding what to do for the near eye, but it probably still be another LAL. But for a near eye, some kind of multi-focal or EDOF is still under consideration, and the non-operated eye has a milder cataract."

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My thinking is very similar, except that I have to do the near eye first, because that's where the cataract is. I had a hard time deciding on a near eye lens and I, too, considered LAL, multifocal and EDOF. I finally decided on LAL, partly because people seem to get pretty good EDOF results in near-eye LALs, and I am thinking that is the best compromise - mostly monofocal, but some extra depth of field.

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If (or when) I need an artificial lens for my distance eye, I plan to get a second LAL, same as you, without any attempt at extra depth of focus. Unless something better comes along in the meantime. I figure on the distance eye, it's even more important to get close to zero sphere/cylinder, and the adjustable lens gives the best probability of that outcome.

Another consideration for the near eye is that you can generally adjust the distance for viewing within limits (hold the ingredients label closer or farther)... move your head farther from or closer to the computer monitor.

Yes, I've been doing a lot of that lately, as my near eye has gotten extremely nearsighted due to the cataract. I now need to read fine print at about 6 inches from my eye. I am hoping to minimize such movements with the new lens.

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For the far eye, I will aim for "perfect" vision at infinity, so no EDOF. For the near eye, I think any IOL is a compromise, so I don't mind minor EDOF distortions if I end up with "pretty good" vision at a reasonable range of near and intermediate distances.

Is your thought - using 2 refractions, 1st not dilated and 2nd dilated, before a LAL adjustment will have more exacting results? Technically, should the 2 refractions be the same?

Two refractions sound best to me. If they agree, great. If they do not, I am proposing to use an average. If only one, then after dilation seems best, with the provision that the room and target can have reduced light appropriate to a dilated eye.

Also, in doing a refraction, there are cases where two values give the same acuity. I think in the case of eyeglasses, they routinely choose the lowest absolute value. In the case of an LAL adjustment, I am thinking that might not be best. Instead I propose to use the other as at least a tie breaker.

Now suppose they disagree? That would imply that either the center of the lens has a different refraction than the outer part, or that one of the methods was less sensitive to differences --or both. I think some EDOF lenses do that on purpose-- focus closer in the middle, and farther away from the middle. I think the plan is that you would use a brighter light for reading.

How many refractions does the optometrist do before the LAL adjustment? Is there a standard they follow?

How many refractions does the optometrist do before the LAL adjustment? Is there a standard they follow?

One.