Have you considered that you might have nasal fungus/mold in your sinus passages? ENT doctors in my experience don't consider this. After seeing three ENT doctors who all just gave me steroid sprays (which are not good for my glaucoma) which just treat symptoms and not the cause, I then went to a naturopath and she found that I had an intolerance of certain molds by intolerance tests (or you can get an expensive blood test to confirm the existence of molds in your blood). I am now being treated for the molds and am having some good results. I have had bad sinuses and eustachian tube disfunction cause loss of hearing for more than two years.