Agree with caregiver, if you are having frequent sinus infections, see an ENT.
And it's true that sinus infections become encapsulated, good term, and antibiotics can't penetrate the mass. The most effective treatment then is to wash out the mass with saline. Saline rinses and sprays won't work if the problem is in the upper sinuses, but a Sinus Flush works well, which I will recommend only if the antibiotics don't work:
http://www.medhelp.org/user_journals/show/2322
The Flip-Turn Sinus Flush is mildly risky, because you have to bend over to do it, preferably in a shower, but you can also do it outside on soft ground, or you can kneel down and lean over a bathtub with the shower running.
If you are lucky, and there are no physical blockages such as polyps (which is why ENT is recommended) it will end your chronic.