It started four years ago, the lower part of my right eyeball turns red , it lasts about three weeks. I go to the eye doctor and he tells me to go for an Xray for the back of my eye, everything is normal. One year later this happens again, I go back to the doctor, he tells me he doesn't know why it happens. Six months later it happens again, this time my face around my eye hurts,its all red on the lower half of my eyeball, for around four weeks. It now happens every three months, only now the pain hurts more. My vision is never affected by this, nor is there any swelling.Do you have any idea what this is? I have seen two doctors already, no one knows what is wrong. They tell me every once in awhile someone comes in with this problem, and they just don't know what it is.BTW these are MD and F.A.A.O F.A C.S.Do you have any ideas...Thanks.