<unk> es are air-filled spaces, communicating with the nasal cavity, within the bones of the skull and face. Humans possess a number of<unk> es, divided into subgroups that are named according to the bones within which the sinuses lie:
the maxillary sinuses, also called the maxillary antra and the largest of the<unk> es, are under the eyes, in the maxillary bones (cheek bones).
the frontal sinuses, over the eyes, in the frontal bone, which forms the hard part of the forehead.
the ethmoid sinuses, which are formed from several discrete air cells within the ethmoid bone between the nose and the eyes.
the sphenoid sinuses, in the sphenoid bone at the center of the skull base under the pituitary gland.
Paranasal sinus
Outer ear
Lacrimal bone
Ear canal
Nasal cavity
Mastoid process
Cauliflower ear
Carotid sinus