Osteology of the nose (dave's notes) Flashcards
List the paranasal sinuses
Frontal
Maxillary
Ethmoidal
Sphenoidal
Discuss the development of the paranasal sinuses
The frontal is absent at birth, the others are rudimentary, expanding between 6-7 years of age and again at puberty
Where is the maxillary sinus found? What shape is it?
In the maxilla, pyramidal.
Where is the ethmoidal sinus found? What form does it take?
Between the orbit and the nose in the lateral part of the ethmoidal bone, divided up into numerous cells.
Where is the sphenoidal sinus found?
The body of the sphenoid
Discuss the development of the frontal sinus in more detail
The frontal sinus is the only sinus absent at birth, appearing in the second year. These are really anterior ethmoidal air cells that have migrated up.
What is the base and apex of maxillary sinus?
Base is the lateral wall of the nose. The apex is the zygomatic process of the maxilla.
What is the roof and floor of the maxillary sinus?
The roof is the floor of the orbit. The floor is the alveolar part of the maxilla.
Where is the maxillary sinus found relative to the nasal cavity? How does it appear at birth?
The maxillary sinus lies lower than the floor of the nose. It begins as a narrow slit at birth.
Where is the ostium of the maxillary sinus?
High up and well back on the nasal wall.
What is the lateral wall of the ethmoidal sinus?
The medial wall of the orbit. Paper thin.
What is found on the medial wall of the ethmoidal sinus?
The superior and middle nasal conchae
What closes in the ethmoidal sinus?
The orbital part of the frontal bone.
Where is the sphenoidal sinus initially found? Where does it extend as it enlarges?
Initially lies in the pituitary fossa. Extends backwards into the basiocciput as it enlarges.
What are the superior relations to the sphenoidal sinus?
The pituitary fossa and the middle cranial fossa
