External nose and nasal cavity (dave's notes) Flashcards
What are the constituents of the external nose?
Nasal bone (bridge) and nasal cartilages supported in the midline by the septum
What is the covering of the external nose?
Skin with many sebaceous glands. The skin extends into the vestibule of the nose.
What are the four arteries of blood supply to the external nose?
The dorsal nasal artery (a branch of the ophthalmic artery), the external nasal artery (anterior ethmoidal) and lateral nasal (facial) and septal artery (superior labial)
What landmarks mark the start and end of the nasal cavity?
The nostrils to the posterior end of the nasal septum
What three areas are found within the nasal cavity?
The vestibular area - just inside the nostril
The olfactory area with receptors for smell
Respirartory area
Describe the lining of the respiratory area of the nasal cavity
Respiratory area is lined with respiratory mucous and pseudo stratified ciliated columnar epithelium
What is the floor of the nasal cavity?
The roof of the mouth/hard palate
What creates the lateral wall of the nasal cavity?
The medial wall of the orbit above (with ethmoidal air cells in between) and the medial wall of the maxillary sinus
What is the roof of the nasal cavity?
The roof is very narrow, with the medial and lateral wall very close together
How many nasal conchae are there? Which is the largest?
Three, the lowest is the longest
How are the middle and upper conchae related to one another?
They are joined anteriorly
What spaces are associated with the nasal conchae?
Each has a space beneath it - superior, middle, inferior meatus. The sphenoethmoidal recess is uppermost.
What opens into the sphenoethmoidal recess?
The sphenoidal sinus
What enters the superior recess?
The posterior ethmoidal air cells
What enter the inferior meatus and where?
The nasolacrimal ducts, two centimetres behind the nostril