DESPERATE chronic sinusitis in 7 year old.

My 7 year old daughter has suffered with chronic sinusitis since she was about 2 years old. She has breathed mostly through her mouth since then and as a result her teeth have suffered. She is permanently congested and has difficulty breathing at night...she snores heavily and sometimes seems to gasp for air. Her nose is constantly blocked and even after she blows out some of the mucous, the heavy congestion is still very audible as it seems it is deep in her sinuses. I took her to an ENT several years ago because her adenoids and tonsils were large but she said she didn't think it was necessary to remove them yet. Needless to say, removing them is not something I am willing to do unless it is an absolute last resort. I have taken her off dairy for a long period and although it did help a bit, it did not resolve the problem. When she goes through a bout of extra heavy congestion, her hearing also suffers significantly, but it seems to return to normal after a couple of weeks. Her voice is very nasal and has been for as long as I can remember. I use a neti pot on her a couple of times a week, but on some days it take a long time to even get a few drips of saline water to go through her sinuses because she is so blocked up. After we do it, she is able to breathe lightly through her nose for a few minutes but you can still hear the gurgle of mucous in her sinuses. I have used homeopathy on her before for other aliments and on occasion we have had a lot of success with it. It breaks my heart to see my daughter struggling to do what most people to with ease: breathe. I am at my wits end and am desperate for help!!!