Less acuity with IOL than with OEM lens

Discussion in 'Optometry Archives' started by Liz, May 9, 2010.

  1. Liz

    Liz Guest

    Today, 12 days after cataract surgery, I tried using birding optics
    with the new eye.
    I looked through my 8x binoculars and 40x spotting scope.
    I saw reasonably well through this eye until 18 months ago, and
    through the other (still unoperated) eye until 9 months ago, so I
    remember how things looked.


    The resolution is poorer than it was through my biological lens.


    Fine details of objects seen through both the binocs and the scope
    never look tack-on sharp; I turn the focus wheel past the right point
    by mistake, looking for focus that doesn't exist.


    Of course, the view is a zillion times better than with the cataract
    (!!). The fact that the doctor was able to get a partly liquified and
    partly hardened lens out of my eye without any serious medical
    problems (AFAIK) is a huge relief, as good as I could hope for.


    Regardless, I still must get a second lens in my other eye, which is
    not such a mess.
    And a lot of what I do is look through microscopes and telescopes at
    small insects and distant birds, trying to see fine detail.


    So it seems reasonable to wonder whether another type of IOL might do
    any better. Mine is the Alcon SA60AT (non-aspheric).


    I wonder if the imperfect resolution is the result of spherical
    aberration (the IOL is about +0.20 um and my cornea before surgery was
    about +0.15).


    Or whether it's because I used to be farsighted and am now nearsighted
    (they targeted -0.5D; I ended up -1 D). Perhaps if I were still
    hyperopic, things magnified would be sharper.


    Or whether acuity inferior to that of the original human eye is common
    to all IOLs, such that another kind would be no different.

    Anyone know?

    cheers,
    Liz
    Indianapolis
     
    Liz, May 9, 2010
    #1
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  2. Liz

    Charles Guest

    It takes a while for the eye to heal. I would not draw any conclusions
    for six to eight weeks about your final acuity.
     
    Charles, May 9, 2010
    #2
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  3. Liz

    Liz Guest

    Today, 12 days after cataract surgery, I tried using birding optics
    Yes, that's what they said about healing too.
    I'm not sure how well the healing process correlates with any changes
    in vision, because I don't know what inside is healing or changing -
    do you know?

    Also, how long until one's focal distance is presumed stable? Mine
    seemed to change a bit during the first several days, but not in the
    past seven.

    (And how do you measure that, anyway? I stood some 2" high letters
    against a wall, and moved forward and back until they were in focus,
    which is at about 3.5 feet. That probably isn't the right way.)

    I'm thinking the poor light yesterday (overcast and stormy) probably
    had something to do with the acuity, and am checking again today in
    bright sun and at dusk.

    Liz D.
     
    Liz, May 10, 2010
    #3
  4. Liz

    Jane Guest

    My vision with aspherical monofocal IOLs is at least as good as my
    best-corrected vision was before cataract development (and slightly
    better at night.)

    If your refractive error is -1, your distance vision will not be
    optimal without glasses. Your computer vision should be pretty good
    without correction.
     
    Jane, May 10, 2010
    #4
  5. Liz

    Dr Judy Guest

    Most likely due to having had surgery only 12 days ago. There is
    still inflammation in the eye.

    Wait until after your final post op check up when you have finished
    all the drops (4-5 weeks from now) before making a judgement about the
    quality of the vision.

    Judy
     
    Dr Judy, May 10, 2010
    #5
  6. Liz

    Liz Guest

    re acuity:
    It was the poor light. I have the telescope focused on some spruce
    branches. The detail I can see on the cones and needles during the
    day melts away as the light starts to die at dusk. Probably loss of
    acuity in dim light is not an earthshaking revelation. *sigh* :)

    best-corrected vision was before cataract development (and slightly
    better at night.)


    Phew - that's good to hear.


    It's not. Last night I got distance glasses, even if temporary, so I
    can see better to drive.


    OK. I'm taking drops of Omnipred (prednisolone) and Xibrom
    (bromfenac) for 4 weeks. I worry that I should be having someone
    check my eye pressure at some point during this.....?

    -1.00. .... your technique is accurate at the 1-diopter point....


    If my scrip for distance is -0.5D spherical, with -0.5D at 55 degrees
    cylindrical........
    then is my "focal distance" -1? or -0.5?


    thanks,
    Liz
     
    Liz, May 12, 2010
    #6
  7. Liz

    Dr Judy Guest

    The eye pressure would have been checked at your 1 day and 1 week post
    op visits.
    Yes. It is -1.00 in one meridian and -0.50 in the other.

    Judy
     
    Dr Judy, May 13, 2010
    #7
  8. Liz

    Liz Guest

    OK.   I'm taking drops of Omnipred (prednisolone) and Xibrom
    It was. It was 22 at the 1 week. This makes me wonder if it needs
    checking again sooner than 3 weeks from now (the one month post-op is
    actually at 5 weeks because of Memorial Day).
    Hmmm. See next post...

    cheers,
    liz
     
    Liz, May 13, 2010
    #8
  9. Liz

    Liz Guest

    If my scrip for distance is -0.5D spherical, with -0.5D at 55 degrees
    I understand.
    OK, I follow this.
    But then, if I want the second eye to match the first one, what target
    distance would be that target? Just -0.75? Should the astigmatism
    in the second eye be part of this calculation? I think it's about
    half a diopter too (not sure).
    (For the sake of the calculation, just assume that they could hit the
    target, even though we know there will be some fudging and error.)

    thanks,
    Liz
     
    Liz, May 13, 2010
    #9
  10. Liz

    Liz Guest

    ... if I want the second eye to match the first one, what target distancewould be that target? Just -0.75? Should the astigmatism in the second eye be part of this calculation?


    I do....


    OK.


    If the right eye already has astigmatism, should be that calculated
    into the target?


    The focus should get more distancy as it heals?


    Is that because you'd rather have the second eye at -0.50, rather than
    having it match the first eye? Or because you think a target of -0.50
    would tend to give a result of -0.75 to -1.00?


    (My own goal is to have them match - god knows I'm confused enough
    without having them different.)


    cheers,
    Liz
     
    Liz, May 14, 2010
    #10
  11. Liz

    Liz Guest

    Am buried and will reply in a few days.

    cheers,
    L.
     
    Liz, May 18, 2010
    #11
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