Did you consult an ENT?  Who interpreted the CT scan for you?

Trish:
What they mean is that they do not see unusal swelling anywhere.
Period.
A CT scan only registers density differences.
They can tell if one of your sinuses is filled with something, or
if they did not up the voltage too high, they can tell how thick the
lining of th sinuses over the bone is..
But I have seen a lot of CT scans without the benchmarks and density
references that
I would normally expect to use to judge the quality of an X-ray.
Especially one that uses FT and image processing software. If the
voltage is too high
everything is black and the ability to distinguish details of soft
tissue goes away.

The gold standard for diagnosis is supposed to be the MRI, because
properly done it can
distinguish tissue from goo.

I have been wondering if a gallium scan could be done of the
sinuses.
Radioactive Gallium sticks to the bugs and inflamation, and lights up
the infected site on an x-ray film,
however I can see that the bones of the skull make it really hard to
get any information about the status
of the sinuses, or maybe not. Worth asking if it can be done.

Some chemical engineers are working on a dye that sticks to the goo
and turns it a bright floresent
pink while not tinting healty tissue, so when the ENTs look though
their endoscope they can tell the biofilm goo eating you, from you.
(though making it glow firefly green is more fun, but the more uptight
type of ENT may call security on you.)