Empyema of the ethmoid cells may be divided into acute and chronic, and the latter usually is followed by the latent.
The mucous membrane of the ethmoid is far more sensitive than that of the nose and consequently more readily succumbs to infection or to any kind of irritant; for that reason we find it so often affected when the nose is supposed to be the actual or natural habitat. Thus the ethmoid is always affected in hay-fever or any infectious disease involving the nose.
It is difficult to speak of ethmoid empyema per se, as such a condition probably never exists, at least it has never been demonstrated, the other sinuses being more or less involved; but it does not follow that treatment directed to the ethmoid will not relieve other contiguous cells as well. Empyema in early childhood is more amenable to treatment than that of the adult