The role of local gas composition in pathogenesis of maxillary sinus empyema.

An impaired ostial function may be of importance in the pathogenesis of the maxillary sinus empyema due to changes of the antral gas composition. Oxygen is usually not demonstrable in purulent sinus secretion while carbon dioxide accumulates. In vitro, pneumococci were able to create a similar gas environment, provided that the gas exchange between the medium and the atmospheric air was reduced. It is suggested that heavy antral growth of facultative anaerobes, such as pneumococci, is related to the antral ventilation, which when impeded facilitates bacterial growth.