One more thought. I had two shots of cortisone injected into L-5 at the end of Nov 2008. My DCR was Jan 12, 2009 when I had cortisone IV and I had another IV cortisone when I had my FESS on Mar 10, 2009. Could that contribute to antibiotics not working?
I am in otherwise good health with no diabetes and no history of an inability to fight infection. Cultures from FESS turned out negative. Are there other causes for the problem?
I suppose that is a remote possibility but these silicone type implants are extremely bio-compatible so overall, I am doubtful. What is more likely is that you have terrible sinusitis, possibily a reduced ability to fight infection (diabetes?) and possible a resistant bacteria.
MJK MD