Head and Neck: Anatomy of the Nose and Paranasal Sinuses Flashcards
What are the functions of the nasal cavity?
- olfaction
- filters inspired air (traps particles in nasal hair and mucus)
- moistens and warms inspired air
- changes the quality and character of voice
What is the external nose made up of?
External nose is made up of the nasal bone, frontal process of the maxilla and cartilage (cartilage determines the shape).
What action do you take if there is fracture of the nose?
Think about other facial injuries - there would have to be a reasonable amount of force to the face to break the nose
Wait for the swelling to subside (5-7days) and then reset the bone
What are the boundaries making up the nasal cavity?
Rood: nasal, frontal, ethmoid and sphenoid
Lateral wall: maxilla bone, has projections called turbinates
Floor: the roof of the oral cavity
Medial wall: the nasal septum
What structures make up the nasal septum?
The anterior portion is septal cartilage
The posterior inferior portion is the vomer bone
The posterior superior portion is the perpendicular plate of the ethmoid bone
What is the crista galli?
A projection of the ethmoid bone
An upward force can cause it to tear the dura leading to CSF rhinorrhoea
What is a septal haematoma?
Look up the nostrils - can see cherry red bumps
Trauma to the nose can cause shearing of blood vessels causing blood to accumulate between the perichondium and cartilage - if untreated will get saddle nose deformity
The blood needs aspirating and the nasal cavity needs packing to squash the perichondrium against the cartilage
What is a saddle nose deformity?
An untreated septal haematoma leads to avascular necrosis of the cartilaginous septum - this occur in a few days
What is the name of the region above the superior concha?
The spheno-ethmoidal recess
What type of epithelia lines the nasal cavity?
Pseudostratified columnar ciliated epithelium
What drains into the nasal cavity?
The paranasal sinuses and the nasolacrimal duct
What nerve carried general sensation from the nasal cavity?
Trigeminal
What are nasal polyps?
Benign fleshy swelling which arise from the nasal mucosa - usually appear pale or yellow. Common in 40+
Symptoms: blocked nose and watery rhinorrhea, decreased smell and taste
NB They are usually bilateral so if unilateral they are a tumour until proved otherwise
What is the blood supply to the nasal mucosa?
The anterior and posterior ethmoid arteries which are branches of the opthalmic artery.
The sphenopalatine artery which is a branch of the naxillary artery
The anastamose at Keisselbachs plexus
How do you treat epistaxis?
Pinch the nose just anterior to the bony part and lean forward. (this should tamponade bleeds from keisselbachs plexus)
If after 15 mins it hasnt stopped then either anterior packing (nasal tampons) or cauterisation should be considered.
If not there will need to be posterior packing (if bleeding from the sphenopalatine artery) which is uncomfortable for patients.
