Describe the skeleton of the external nose?
Frontal process of maxilla
Describe the skeleton of the nasal cavity?
LATERAL WALL: frontal bone, ethmoidal bone, maxilla, palatine bone, sphenoidal bone
MEDIAL WALL: septal cartilage, cribiform plate of ethmoid, vomer
What are the openings of the nasal cavity?
Why is damage to the ethmoid bone particularly dangerous?
It is in close contact with the brain and meninges
Breaks may lead to infection, bleeds and rhinorrhea
What is the vestibule?
Small entrance to the nasal cavity
What is the vestibule lined by?
Skin and hair
What is the nasal cavity lined by?
Highly vascular mucous membrane (lines all except vestibule, which is lined by skin and hair)
What is the function of the highly vascular mucous membrane?
Helps warm and humidify air
Mucous traps foreign particles
What are the two parts of the highly vascular mucous membrane on the medial wall of the nasal cavity?
Olfactory area (superior 1/3): olfactory epithelium
Respiratory area (inferior 2/3): respiratory epithelium
Which cranial nerve relates to the nasal cavity?
Olfactory nerve (CN I)
Enters via cribiform plate of ethmoid bone
Describe the features of the lateral wall of the nasal cavity?
Turbinate bones: conchae
What are the conchae lined by?
Highly vascular mucous membrane
What is the function of the conchae?
Produce turbulence in air that we breathe in
Describe the spaces that relate to the turbinate bones?
Describe the paranasal sinuses?
Describe the drainage of the paranasal sinuses?
Frontal, ethmoid and sphenoid drain downwards into nasal cavity
Maxillary opening is high up in sinus
Describe the innervation of the paranasal sinuses?
Why is this important?
Frontal, ethmoid and sphenoid: V1
Important in referred pain
How does the eye communicate with the nasal cavity?
Travels from eye and opens in inferior meatus
Describe the blood supply of the nasal cavity?
Same for lateral and medial walls
Derived from carotid arteries
Superior quadrant: anterior and posterior ethmoidal arteries
Anterior quadrant lateral: Lateral nasal branches of facial artery
Anterior quadrant medial: superior labial arteries
Inferior quadrant: greater palatine artery
Posterior quadrant: sphenopalatine artery
What is epistaxis?
Which artery is responsible for forceful nose bleeds?
Big, thick artery
Decsribe the innervation of the nasal cavity?
Superior: branches of anterior ethmoidal nerves (V1)
Inferior: branches of greater and esser palatine nerves (V2)
Desribe the borders of the pharynx?
Base of skull to C6/lower border of cricoid cartilage
Describe the constrictor muscles of the pharynx?
Superior, middle and inferior constrictor muscles
What is the median raphe?
Conective tissue line where constrictor muscles meet in midline
What is the function of the constrictor muscles?
Contract sequentially when swallowing
Describe the features of the nasopharynx?
Opening of auditroy tube
What is the function of the salpingopharyngeus muscle?
Contracts to open auditory tube