Smog's visit to the vet yesterday was notably inconclusive. We know now that: He doesn't have Horner's disease; he doesn't have uveitis; his eye pressure is normal and there was no sign of trauma. He is not blind; doesn't have glaucoma and is in no pain.
What he's got is idiopathic anisocoria which is a clinician's way of saying that his eye has gone all weird and nobody knows why.
He is, however, a lot better today. His eye is slowly returning to normal and he's showing no other symptoms except the tendency to attack unseen foes and run straight up the trunks of trees.