Paul

I only have been scoped twice, but I do not think they can look into
your ethmoids. That's why they
do the CT scan (or at least one reason.)

The doctor cannot see into any of the sinus cavities directly via the
endoscope, unless the sinus ducts have already been widened out by
previous sinus surgery.

The sinus ducts are only 2 mm wide, too small to look through and too
small to push the endoscope through without general anesthesia.

The endoscope is used to image the osteomeatal complex, which is the
region that the maxillary, ethmoid and frontal sinus ducts drain into.
The doctor can see what's oozing out of the sinuses but he can't see
inside them.