The Nose Flashcards
What are some of the functions of the nose and the nasal cavity?
Sense of smell (olfaction), provides routes from inspired air, filters inspired air, and moistens and warms the insprid air, and resonating chamber for speech
What are some of the features of the bony framewok of the external nose?
Bony part is the nasal bone and the frontal proccess of the maxillla, and there is the cartilagnous part- which consists of five main cartilages, two lateral, 2 alar, and one septal
Why are the nasal bones suspectible to fracture in facial injuries?
Commonly occur as a result of blunt trauma, and disruption of the nasal septum cartilages may als occur, and you may have to wait until some of the swelling has gone down to try and reset the bone and when injury is from a direct blow, the cribiform plate of the ethmoid bone may also fracture
What are the divisions of the nasal cavity?
Vestibule-the area surrounding the anterior opening of the nasal cavity
Respiratory region- lined by a pseudostratified epithelium, and interspersed with mucus secreting gobelt cells
Olfactory region- located at the apex of the nasal cavity
What are the boundaries of the nasal cavity?
Floor- the hard palate and also the soft palate
The medial wall is formed by the nasal septum
The lateral walls are formed by the maxilla
The roof- posterior end is formed by the hollow body of the spenoid
What are the three main parts of the nasal septum?
The septal cartilage, the perpindicular plate of the ethmoid, the vomer
What is the clincal significance of the crista galli?
A projection of the cribifrom plate, a fracture of the ethmoid can tear through the brains dura dn cause CSF to leak out of the nose, and the olfactory bulb in the the cribiform plate can be damaged irrreversibly, and exposing the brain to the outside environment can increase the risk of mennigits
What is a septal heamotoma?
The cartilagnous part of the septum relies on the overlying perichondrium for the blood supply, and here a blood clooext between the septum and the perichondrium, and the blood supply is stripped away, and pressure can cause ischamia of the cartilage
What are some of the possible affects of a untreated septal haemotoma?
Leads to avascular necrosis of the cartilaginous septum, causing a saddling nasal deformity, and can also develop an infection in the developing heamotoma, and septal abscess formation further increases the likelihood of avascular necrosis of the septum.
What are the two types of epithelium found in the nasal cavity?
There is an olfactory mucus membrane for olfaction, and there is a respirtory mucus membrane which is pseudostratified ciliated columnar epithelium, filters, humidifies and warms
What are the structures that drain into the nasal cavity?
The paranasl sinuses, the nasolacimmal duct and the eustachian tube
What is the nerve that is involved wiht sensation in the nasal cavity?
The trigeminal, with general sesnation to the septum and the lateral walls being devlivered by the nasopalint never which is a branch of the maxillary nerve, and the nasociliary nerve which is a branch of the opthalmic nerve
What are nasal polyps?
Flesy benign swellins arising from the nasal mucosa, pale and yellow in appearance or fleshy and redeneed, and are often found bilaterally.
What are some of the symptoms of nasal polyps?
Blocked nose and watery rhinorrhea- as the polyps are mucosa lined and can drain water, there is a post nasal drip, and there is also a decreased smell and a reduced taste- however unilateral polyps with a blood tinged secretion may suggest a tumour
