A model developed in the past 5 years is that of the "Unified Airway." The concept in this model is that the respiratory mucosa from the middle ear, through the nose and sinuses, down the trachea and through the larynx, and into the bronchioles represents a common epithelium that responds to stimuli in a similar manner. Diseases that affect one portion of this epithelium, therefore, will commonly affect one or more other components. This model has...