Making the Diagnosis
Computed tomography (CT) scans usually reveal the extent and location
of infection in the sinuses. For acute sinusitis, usually your doctor will
arrive at a diagnosis based on history (e.g., a recent cold), symptoms, and
an examination. During the examination your doctor may shine a light onto the
roof of your mouth in an effort to see through the translucent wall into the
lower (maxillary) sinuses.
If there's a discharge coming out of the nose, bacteria can be cultured from
it. They can be identified under the microscope. If the first antibiotic used
doesn't work, others can be tested on the cultured bacteria to check effectiveness.