sphenoidal sinus n.
Either of a pair of cavities in the body of the sphenoid bone that communicate with the nasal cavity.
The operation for draining the sphenoidal sinus is extended by removing the inner wall of the posterior ethmoidal cells.
Suppuration in the sphenoidal sinus (Fig. 267) is characterised in many cases by the presence of eye symptoms.
If the sphenoidal sinus be suppurating, its orifice will have been enlarged.
The posterior ethmoidal cells (Fig. 267) are frequently affected along with the sphenoidal sinus.
The anterior wall of the sphenoidal sinus can be opened with safety.
It is perhaps more common for reinfection from the sphenoidal sinus to be overlooked.
The sphenoidal sinus should be catheterized, and, if infected, the orifice will require enlarging and the cavity treating.
The mouth of the sphenoidal sinus is often indicated by the muco-pus oozing from it or pulsating in harmony with the pulse.
Attempts to reach the sphenoidal sinus from the naso-pharynx are not practical.
It has been proposed to approach the sphenoidal sinus by first traversing the maxillary antrum.