I noticed yesterday that my husband has a white circle on the white of one of his eyes. It is not on the cornea. He didn't even know it was there. Today, it is still there and he said he said it feels itchy. He has never had a problem with his eyes before.

Any ideas on what this might be and does it need medical attention right away or should we wait a few days to see if it goes away on its own?

Thanks, Julie