If I were you I would surely get some colloidal silver, apply it directly to the eye by using drops from an eyedropper and also put some in your dogs drinking water. They love colloidal silver in their water. You may well clear up the eye problem and as an added bonus see your dog regain lost energy and youthfulness.
Try it and come back and tell us all how it worked out. As many in CZ can tell you, colloidal silver works wonders for pets. People too.
The best colloidal silver, imho, is that made by CureZone sponsor Utopia Silver. New buyers can buy-one, get-one free. Any time it is not on sale, CZ members can get 15% off of the silver and any other product they sell by using the discount code LR001.