The diagnosis of sinusitis is made primarily on the basis of the symptom history and the physical examination. Sometimes it may be necessary to perform one or more procedures to confirm the diagnosis, including:

Nasal endoscopy: A spray is applied to the inside of the nose to numb it. The doctor then painlessly inserts a very small scope into the nasal cavity to evaluate the intranasal anatomy and the presence/absence of infection.

CT Scan: This special type of X-Ray is not routinely performed for the initial diagnosis of sinusitis, but it may be needed in certain situations. If symptoms have failed to respond to medical treatment, if the presenting signs/symptoms are unclear, or if a complication of an infection is suspected, then this test may be necessary.

The San Diego Sinus Center has a CT scanner in the office specifically designed for the sinuses. It emits 82% less radiation than the machines typically found in hospitals and imaging centers and creates much more detailed images than those machines. The sinus scan is completed in 20 seconds.