2yr old Australian Cattle Dog mix. Active, hyper but well trained and exercised frequently.

Is this a concern? How long has it been going on? Are there any other health concerns? Have you discussed this concern with a vet?

Sometimes the retina's of the eye detaches giving the dog dilated pupils. Although this is not a painful thing, it still should be confirmed with a vet. The dog is also basically blind and sometimes this is hard to discover if it's sudden like this because dogs can navigate in the home and yard quite well without vision.

As far as I know, there is no way to reattach the retina. I've seen this in older dogs, but like most diseases, that doesn't mean a younger dog cannot have this problem as well.

Has your dog been walking into things or more cautious?

If this were my dog, even if he's not in pain, I would have it checked out by the vet. It could be something else other than detached retinas.