Nose Week 3 FINISHED Flashcards
What is the function of the nose nasal cavities?
- filtration of dust
- respiration (breathing)
- olfaction (smell)
- humidification of inspired air, warms and moistens before passing to rest of respiratory tract
- receives secretions from the paranasal sinuses and nasolacrimal ducts
What divides the nasal cavity into right and left cavities?
It is divided into 2 cavities (lt and rt) by the nasal septum
What are the parts of the external nose? (point to them)
Root Dorsum Tip or apex Nasal septum Alae of the nose (alae , plural) (ala , singular) alae = wings
What does nare/nares mean? What different nares do we have?
Opening into the nasal cavity. We have anterior and posterior nares (posterior nares open posteriorly into the nasopharynx), (anterior nares are the opening anteriorly)
What are the posterior nares also known as?
Posteriorly called the choanae (between the nasal cavity and the pharynx)
What are the anterior nares also known as?
Anteriorly called nostrils (nasal cavity to outside)
What bones make up the nose?
Nasal bones
Frontal process of the maxilla
Nasal parts of the frontal bones and its nasal spine
How many bits of cartilage are there in the nose? What are they?
10
5 main cartilages
2 lateral cartilages
2 alar cartilages
1 septal cartilage
How many parts does the nasal septum consist of? What are they? What else contributes a small amount to the nasal septum?
3
Perpendicular plate of the ethmoid
Vomer
Septal cartilage
Also includes small sections of the palatine and maxillae, called the nasal crests
Describe the perpendicular plate of the ethmoid
It descends from the cribriform plate superiorly, it is continuous superiorly with the crista galli
Describe the vomer
A thin flat bone found posterior and inferiorly
Describe the septal cartilage
Its is continuous inferiorly and anteriorly with the bony septum.
What are the size dimensions of the nasal cavity?
Height 5 cm
Length 5-7 cm
Roof 1-2 mm
Floor 1.5 cm
What are the vestibules of the nasal cavities lined with? What is the rest of the nasal cavity lined with?
Skin and stiff hairs line the vestibules, and then rest of the cavities are lined with mucous membranes
What is a vestibule?
A cavity situated at the entrance to a hollow
What is the entrance to the nasal cavity and what is the exit?
The entrance in the nostrils anteriorly, and it opens posteriorly into the nasopharynx through the choanae (funnel shaped openings)
What are the mucous membranes of the nasal cavities attached to?
Firmly bound or attached to adjacent periosteum and perichondrium
What are the mucous membranes of the nasal cavities continuous with? What are these areas?
They are continuous with all the cavities with with the nasal cavity is continuous. e.g.:
- nasopharynx posteriorly
- paranasal sinuses (frontal, ethmoid, maxillary, sphenoid)
- lacrimal sac and conjunctiva superiorly
What part of the mucosa of the nasal cavity is in the respiratory area and what part is the olfactory area?
The inferior 2/3 of the mucosa is respiratory
The superior 1/2 of the mucosa is olfactory
What is the roof of the nasal cavity made of?
How wide is it?
The frontal bone and nasal bones anteriorly
The ethmoid bone in the middle
The sphenoid bone posteriorly
It is narrow, 1-2 mm
What is the floor of the nasal cavity made of?
The palatine process of the maxilla and the horizontal plate of the palatine bone
What is the medial wall of the nasal cavity made of?
It is the nasal septum and is made by the perpendicular plate of the ethmoid bone, the vomer and the septal cartilage
What is the lateral wall of the nasal cavity made of?
It is irregular and consists of 3 scroll shaped protrusions that project inferiorly called the conchae.
What bones make the conchae?
Superior concha - ethmoid bone
Middle concha - ethmoid bone
Inferior concha - inferior concha (separate pair of bones)
What does meatus mean?
An opening or passage
Where are the meatus in relation to the conchae?
They are inferior to the conchae
Where is the sphenoethmoid recess found?
At the opening to the sphenoidal sinuses, superior to the superior concha
What is found in the superior meatus?
The opening for the posterior ethmoidal sinuses
What is found in the middle meatus?
The opening to the: Frontal sinuses Maxillary sinuses The anterior cells (ethmoid bone) The middle cells (ethmoid bone)
What is found in the inferior meatus?
The nasolacrimal duct (which drains tears from the lacrimal duct
What is the arterial supply for the nose?
- Sphenopalatine artery - maxillary artery
- Anterior and posterior ethmoidal arteries
- Greater palatine artery
- Branches of the facial artery
What is the venous drainage of the nose?
- Venous plexus - is important in the body’s thermoregulatory system warming air before it enters the lungs
- Sphenopalatine vein
- Facial vein
- Ophthalmic veins
What is the nervous supply to the nose?
Olfactory nerve for the special sensation of smell
Posteroinferior 1/2 - 2/3 rds = maxillary nerve
Anteriosuperior region = anterior & posterior ethmoidal nerves (nasociliary nerve CN V(1))
Parasympathetic - pterygopalatine ganglion (Facial n)
Sympathetic - carotid plexus (plexus of nerves associated with the carotid arteries)
What are the paranasal sinuses?
Air filled extensions of the respiratory part of the nasal cavity
How many paranasal sinuses do we have? How are they named?
Frontal paranasal sinuses (pair)
Maxillary paranasal sinuses (pair)
Ethmoid paranasal sinuses (many spaces within the ethmoid bone)
Sphenoid sinuses (2)
They are named for the bone they are found in
Where do the frontal paranasal sinuses drain into?
Into the middle meatus
What innervates the frontal paranasal sinuses?
The supraorbital branch of the ophthalmic division of the trigeminal nerve
What are the ethmoidal paranasal sinuses and where do they drain?
They are several cavities within the ethmoid bone called the ethmoid cells.
The anterior cells drain into the middle meatus
The middle cells drain into the middle meatus
The posterior cells drain into the superior meatus
What is the innervation for the ethmoidal paranasal sinuses?
The anterior and posterior branches of the nasociliary nerve (CNV (1))
Where do the sphenoidal paranasal sinuses drain into?
They drain into the sphenoethmoidal recess
What innervates the sphenoidal paranasal sinuses?
The posterior ethmoidal nerve (CN V (1))
Which of the paranasal sinuses is the largest?
The maxillary sinuses
Where may the maxillary paranasal sinuses extend into?
The zygomatic bones
Where do the maxillary paranasal sinuses drain into?
Into the middle meatus
What innervates the maxillary paranasal sinuses?
The branches of the maxillary nerve.
What is the order of structures and meatus’ from superior to inferior in the nasal cavity?
Sphenoethmoidal recess
- opening on the sphenoidal sinuses
Superior concha
Superior meatus
- opening of the posterior ethmoidal sinuses
Middle concha Middle meatus - frontal sinuses - maxillary sinuses - anterior cells (ethmoid) - middle cells (ethmoid)
Inferior concha
Inferior meatus
- nasolacrimal duct
(drains tears from the lacrimal sac)
