Functions of the mastoid cell system: auto-regulation oftemperature and gas pressure

摘要

This article presents a new approach to understanding the physiological functions of the mastoid cellsystem. It is suggested that the cell system, in combination with the continuous blood fow through theadjacent large vessels, makes up a compound functional unit that serves to protect the sensitive vestibularpart of the inner ear from inadequate stimulation by external temperature changes. By virtue of the largesurface area of the cell system mucosa with respect to the enclosed gas volume, the mastoid cell systemmay also work as a pressure regulator. Variations of the bi-directional exchange of fuid over the capillarynetwork in the mucosa will change the size of the lumen that is available for the gas in the cell system.Volumes of gas and fuid can thus be exchanged to keep the intratympanic pressure within physiologicallimits. The process is most effective in a cell system with a high area-to-volume ratio.