Fortunately, cataract surgery seems to work pretty good. I found only this link on research (mostly human but still pertinent):
http://www.opt.indiana.edu/optlib/cataract/opt.htm
I truly would contact this guy:
https://pro.osu.edu/profiles/chandler.111/
I believe some supplements help, but I like research and usually feel if it really worked, there would usually be research to support it. On bilberries and eyes only found this, which suggests because humans who are NOT predominately carnivores may benefit, some may assume dogs have same dietary lack and could benefit:
Ocular Nutritional Supplements
Nutritional supplements may be a beneficial alternative to those who can not consume adequate nutrients directly from fresh fruits & vegetables. Researchers are investigating the claims that certain nutrients are beneficial to eye health. For instance:
1. Bilberry Extract: European studies have suggested that bilberry may be associated with improving night vision and dark adaptation.
No research found on Cineraria for humans or dogs for eye issues, except here which gives a bit alarming other info. Not sure if exactly the same:
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Smoke from the leaves is suggested for eye troubles, but the fruit is said to be indigestible, inducing biliousness, and destroying nails and hair.
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I looked up cineraria, btw, because another forum of it I plant around my mail box (dusty miller is what we call it in the south, but real name is senecio cineraria).
Please note it is listed as TOXIC (just as cineraria) by aspca:
http://www.vspn.org/library/misc/vspn_m01235.htm