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    Aniseikonia issue

    Hi everyone I have a patient with the following Rx:

    OD: -6.50/-4.00x12 VA 6/7.5
    OS: -5.00/-9.25x168.5 VA 6/9

    What is the best thing I can do to keep image size as similar as possible?
    I have already reduced vertex distance and measured vertical and horizontal centration accounting for pantoscopic tilt.

    Thanks in advance

    #2
    Have you tried the Shaw lenses? Amazing results.

    Comment


      #3
      Originally posted by NESDO View Post
      Hi everyone I have a patient with the following Rx:

      OD: -6.50/-4.00x12 VA 6/7.5
      OS: -5.00/-9.25x168.5 VA 6/9

      What is the best thing I can do to keep image size as similar as possible?
      I have already reduced vertex distance and measured vertical and horizontal centration accounting for pantoscopic tilt.

      Thanks in advance
      Consider reducing the Lt cylinder. Losing a few letters on the 6/9 line might be a good compromise, compared to very complex, bulky, and costly lenses that might, or might not perform as well as modifying the Rx.

      Hope this helps,

      Robert Martellaro
      Science is a way of trying not to fool yourself. - Richard P. Feynman

      Experience is the hardest teacher. She gives the test before the lesson.


      Comment


        #4
        I'm not so sure the Shaw lens would be a great option here. There really is no generalized (360) anisometropia in this case, and anything that Shaw controls is in all meridians..., except vertical prism, of course, but that you can do anyway...which is not likely to work anyway, right? because in primary gaze through the optical centers, you need no prism, but you may have a problem when they lookdown. (or up). (sorry for the run-on sentence here.)

        And it seems you are more concerned about how it looks...and the patient will want this too...and how shall I say, Shaw lenses are a bit...fugly.

        You haven't told us the age of this patient, or whether they are presbyopic, or whether they are used to a similar Rx from before.

        I tend to agree with the other poster that just cutting the OS cyl a bit might be your best solution since that eye is a bit more amblyopic anyway...but again, we don't know what the patient is habitually used to.

        I hope some prescriber is not just bumping up that OS cylinder by 2 or 3 diopters...because that will just not work.

        Comment


          #5
          I know this is an old page, but using a different lens index between each eye would help. Use the higher index on the higher prescription. This is what I have to do on my own specs.

          Comment


            #6
            Originally posted by Loki View Post
            I know this is an old page, but using a different lens index between each eye would help. Use the higher index on the higher prescription. This is what I have to do on my own specs.
            This is unreliable information at best. There are number of factors that are going to determine spectacle magnification and the best way to balance between eyes. Index is pretty low on the list of variables. In the case of minus lenses changing index if basically useless when it comes to magnification. In plus lenses is can help slightly, by way of reducing the center thickness of the stronger plus lens. But base curve and thickness are going to be bigger factors.

            Comment


              #7
              Originally posted by Kwill212 View Post

              This is unreliable information at best. There are number of factors that are going to determine spectacle magnification and the best way to balance between eyes. Index is pretty low on the list of variables. In the case of minus lenses changing index if basically useless when it comes to magnification. In plus lenses is can help slightly, by way of reducing the center thickness of the stronger plus lens. But base curve and thickness are going to be bigger factors.

              As I said, i use this in my own specs. It works for me. Not saying it works for everyone, as everyone is different. I've been using this in my own specs for a couple of years now. I get terrible diplopia if I don't.

              Comment

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