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Old 02-15-2013, 01:28 PM   #44
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Re: Post-Vitrectomy Vision & Possibility of Repeat Retinal Detachment

In trying to see how my visual distortions may reduce in the future, I remember you, or, somebody else on another HB thread, writing that if the difference in diopter numbers between the two eyes is more than 2D then it is difficult for the brain to fuse the two images from the two eyes, and can lead to poor stereoscopic vision. In my case, my right eye is 20/20 for distance but +1.5D for near vision, whereas, the left eye (w/ recent vit. sx.) is 20/50 and I don't know its D for near vision. So, when defining the difference in D for above purposes do we need to compare the D (a) for same distance (far or near), that is, apples to apples, or (b) something else, such as, the worst combo?

For example, in my case, 20/20 is 0D (plano), and 20/50 is about -1D to -1.25D, depending on my astigmatism, although there is no such true one-to-one correspondence, I understand. Does it mean the difference in D for me, for the above purposes, is 1.25D max. (0-(-1.25)) for distance vision, which is smaller than 2D, and, hence, okay for distance stereovision? Or, should I be comparing -1.25D for left eye and +1.5D for right eye, which gives a max. difference of 2.75, and which is higher than 2, and, hence, not good? Somehow, the latter does not sound right because I am mixing corrected vision for different distances. In practice, I know, I can presently see good, natural 3d depth at closer distances than farther, and it is slowly getting better and better (at 5+ weeks).