I am 47 years old and have a thick stringy mucus that I can make come in my throat . It sees to come from my nasal area but my nose is very clear. My ears are stuffed and the pressure in my head is very uncomfortable. Only small amounts of this mucus will come up at a time and whatever this is it seems to bother my eyesight (although maybe eyesight is just an age issue?). My ENT has done CAT scan an MRI and does not see anything. He just sends me home very frustrated. What might this be and I have read something about a possible parasite. Could this be my issue?