[Fundamentals of echographic diagnosis of acute and chronic sinusitis (author's transl)]

Changes of sound permeability in facial bones are caused by inflammatory or tumorous reaction in the mucosa of the sinuses; echo-orbitography (8-10 MHz) shows in this case extraorbital echo signals if bony walls are thin enough (e.g. Lamina papyracea, anterior and upper wall of the antrum). Further examinations of facial bones show early inflammatory changes of bony tissue in sinusitis without influencing the echographic pattern; the amount of hydroxylapatite remains unchanged.