Please HELP!!! Beagle eye problem?

My dog's iris and pupil in one eye have gone completely gray, I'm guessing from blindness caused by some kind of infection. It's also half rolled back into her head, and mostly you can see the white part. My vet had never seen this before, and he gave eyedrops and antibiotics for her, and it was getting better. Then it spread to the other eye, and he was dumbfounded. This eye, however, still maintained its color, so he told us to put the eydrops in both eyes and to bring her back in a week. Has anyone ever seen this before? I'll take anything related, I don't care, I just want my dog to be able to see when (hopefully) this is over. Thanks in advance.