frontal sinus n.
A hollow formed on either side in the lower part of the squama of the frontal bone, communicating by the ethmoidal infundibulum with the middle meatus of the nasal cavity of the same side.
If the frontal sinus is being operated upon, the nose is carefully packed beforehand.
See these peculiarities in the frontal sinus—in sinciput or occiput!
The muzzle more or less shortened, the frontal sinus enlarged, and the cranium elevated and diminished in capacity.
Suppuration in the frontal sinus will have generally been excluded beforehand.
The orbital recess of the frontal sinus itself may run back in the roof of the orbit nearly as far as the foramen opticum.
The ethmoid should be attended to in all cases of suppuration in the frontal sinus.
In other animals, the measurement is generally commenced at the frontal sinus instead of the cerebrum.
Either the frontal sinus was very large, or his observant faculties were peculiarly developed.
Abscess in the frontal cerebral lobe may arise from operation on the frontal sinus.
If the frontal sinus is opened, air may infiltrate the scalp.