What Causes Rashes On Eye Lids And Itching Under Eyes?

I have a rash on my eyelids and under my eyes that is very itchy. This started months ago. It seems to get better and the skin starts flaking off. Then the rash comes back and is itchy again. It has never completely gone away. My ears and behind my ears are also flaky and itchy but I don't think they actually get rashy. What could be causing this?