Acid reflux: Backflow of stomach acid into the esophagus and possibly the throat and nose.

Acute sinusitis: A temporary sinus infection that often follows a cold or allergy attack. Usually causes nasal stuffiness, facial pain and discolored nasal discharge.

Allergen: A substance that causes sensitivity and the release of antibodies and histamine typically causing itching and sneezing.

Allergic fungal sinusitis: A severe form of sinusitis usually associated with nasal polyps and often asthma. Cause is probably an immune (not allergic) reaction to mold and fungus that lives in the nasal mucus of most individuals.

Antrum: Maxillary sinus located in the cheek under the eye adjacent to the ethmoid sinus.

Buffered hypertonic saline: A solution that is three to four times saltier than normal saline and contains baking soda to decrease acidity.

Caldwell-Luc: A surgical procedure where the maxillary sinus is entered by making an opening under the upper lip above the teeth. The procedure is performed rarely today only under special circumstances.

Chronic sinusitis: Sinus infection lasting longer than eight weeks. Symptoms often include nasal congestion, headache, nasal discharge, decreased smell and taste, and cough.

Cilia: Microscopic hair-like structures that line the nose and sinuses. Cilia sweep the mucous blanket along, filtering impurities out of our nose and sinuses.

Concha Bullosa: Enlarged air-filled middle turbinates. Anatomical variation may contribute to sinus disease.

CSF (Cerebral Spinal Fluid): The clear fluid that bathes the brain and spinal cord.

CT scan (CAT scan, Computerized Tomography): Computerized x-ray test that produces highly detailed slices or cross sections of the sinuses and their connections.

Ethmoid sinuses: Paired labyrinth of air cells between nose and eyes.

Fiberoptic esophagoscopy & gastroscopy: A non-invasive procedure where a gastroenterologist examines the inside of the esophagus and stomach with a flexible telescope. Performed with mild sedation as an outpatient.

Frontal Sinuses: Paired sinuses in forehead. Maybe asymmetrical and absent in 10% of the population.

Haller Cell: A variation in sinus anatomy where extra ethmoid air cells develop along the orbital wall narrowing the outflow tract of the maxillary sinuses.

Heartburn (Hyperacidity): The most common symptom of acid reflux. Most people describe a burning pain in the center of the chest.

H2 receptor antagonists: Another group of acid inhibitor medications (Tagamet, Pepcid, Axid, Zantac) which suppress about half the acid of proton pump medications.

Image Guided Surgery: Use of 3D interactive computer generated images for surgical guidance that allows surgeons to monitor the position of surgical instruments during a procedure.

Maxillary Sinuses: Maxillary sinus located in the cheek under the eye adjacent to the ethmoid sinus. (see antrum)

MRI (Magnetic resonance imaging): A highly sophisticated computerized imaging system that uses magnetic resonance not x-rays to provide detailed slices or cross sections through the sinuses and head. CAT scan remains the most useful test for sinusitis. An MRI scan is very useful in diagnosing tumors.

Orbital cellulites: Infection or inflammation of soft tissues of the eye including the eyeball, orbital fat and muscles of the eye. Often spreads from adjacent sinuses.

OMU (ostemeatal complex): The narrow outflow tract area connecting the sinuses to the nose. Problems here are often the cause of ongoing sinus problems.

Pansinusitis: Inflammation or infection in all the sinuses. Often a radiologic diagnosis, it may be seen temporarily following the common cold.

Proton pump inhibitors: Also known as acid pump inhibitor, these medications work by preventing acid pumps in the stomach from producing too much acid. These drugs (Prilosec, Prevacid, Aciphex, Nexium, Protonix, Zegerid) are the strongest acid inhibitors available today.

Septum: The wall that separates the right and left nasal cavities. Made of bone and cartilage. Is often congenitally crooked (deviated septum).

Sinuses: Air filled cavities around the nose which produce mucous for nasal filtering. The sinuses drain into the nose through small openings or ostia.

Sphenoid Sinuses: Paired sinuses behind the eyes. Infection in this area can cause pain

Turbinate: Structures on sidewall of nose. Adds surface area for nasal filtration function

VMR (vasomotor rhinitis): A chronic condition where individuals typically have profuse watery nasal discharge and sometimes congestion. Often related to eating certain foods (i.e. hot soup or spicy foods) or going into different weather or environmental conditions (air conditioned room etc.)