Purdue has an excellent Vet teaching hospital. Your vet might be able to give you a referral there for him to be seen. If it were me I would want to know the level of sights and hearing that he has. It's been a while since Truman was with me and I had forgotten how he would react to me as I would walk. I'd clap my leg and call his name and he would stay right at me heels everywhere I would go.
__________________ “Never argue with a fool, onlookers may not be able to tell the difference.”  Mark Twain |