eye issues

I have a cat that is 11 years old. I noticed yesterday that one of his eyes was dilated more than the other. I check his eyes with a light to make sure they were reative, and the more dialted eye reacted but slower than the other. He acts fine with no other symptoms. Should I be concerned?

[Savas]

You should definitely get this checked. Uneven dilation could be a sign of a few serious illnesses.

[babbs632]

we have 10 cats in our back yard. six are new kittens  and their eyes are crusty and runny like they have cold in them .what natural  stuff can we use to help clear their eyes up. They are not our cats and we feed them. Also want to find homes for them. Help?