Angelfish Eye Problem (strange!) Question

I just bought a few platinum angels from a LFS yesterday. When I got home and put them in the tank, I noticed that one of the angels has different sized pupils in each eye.

See pictures - tried to take one of each eye, then one of his reflection in the glass so you can actually see both eyes.

He seems healthy otherwise. Has anyone ever seen this in a fish? I don't think it's a disease like popeye or cataracts. Do you think he's blind in that eye?

 

I'm thinking birth defect.

 

He can see as the pupil is still visible, but it is a birth defect that doesn't allow him to have as much vision on that side. It cannot be fixed.