Which nerves innervate the bridge and crest of the nose?
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The infratrochlear and external nasal branches of the ophthalmic nerve (CN V1).
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Which nerves innervate the bridge and crest of the nose?
The infratrochlear and external nasal branches of the ophthalmic nerve (CN V1).
How does air interact with the respiratory area of the nasal cavity?
Air is warmed and moistened before passing to the lungs.
What forms the posterior part of the roof of the nasal cavity?
The downward sloping body of the sphenoid.
What structures make up the upper portion of the nasal septum?
The vertical (perpendicular) plate of the ethmoid.
Where do veins that pass with branches from the maxillary artery drain?
Into the pterygoid plexus of veins in the infratemporal fossa.
Which bones are considered peripheral bony elements of the external nose?
Nasal bones, frontal processes of the maxillae, nasal part of the frontal bone, and bony parts of the nasal septum.
What is the significance of the nasal septum in relation to the nostrils?
It separates the two nostrils from each other.
What nerve supplies the side of the nose?
The infraorbital branch of the maxillary nerve (CN V2).
What is the nasal vestibule?
The area of the nasal cavity lying just inside the nostril.
Which vein do veins from the anterior regions of the nasal cavities join?
The facial vein.
Where is the sphenoethmoidal recess located?
Above the superior concha.
What is the role of the vomer in the nasal septum?
It forms the postero-inferior part of the nasal septum.
What is epistaxis commonly known as?
Nosebleed.
What is the function of the inferior two thirds of the nasal mucosa?
It serves as the respiratory area, warming and moistening air.
What artery supplies the nasal cavity from the maxillary artery?
Sphenopalatine artery.
How does the nasal septum typically align in the nasal cavity?
It rarely lies in the midline, causing asymmetry in the nasal cavity sizes.
What is the foramen cecum?
A midline aperture in the frontal bone anterior to the crista galli.
How many main cartilages are in the cartilaginous part of the nose?
Five main cartilages.
What is the neurovascular supply of the nose responsible for?
It supplies blood and nerve function to the nasal structures.
What is the floor of the nasal cavity also known as?
The superior surface of the hard palate.
Which structure constitutes the lower part of the nasal septum?
The vomer.
What is the Kiesselbach area?
An anastomotic arterial plexus involving five arteries supplying the nasal septum.
What type of cartilage primarily makes up the external nose?
Hyaline cartilage.
What is the primary nerve supply for the postero-inferior portion of the nasal mucosa?
The maxillary nerve, via the nasopalatine nerve and branches of the greater palatine nerve.
What are the types of cartilages found in the external nose?
Two lateral cartilages, two alar cartilages, and one septal cartilage.
What function do the alar cartilages serve?
They dilate or constrict the nares when the muscles acting on the nose contract.
Which sinus opens into the middle meatus?
The maxillary sinus.
What is posterior epistaxis?
Bleeding from the posterior or superior nasal cavity.
What forms the medial wall of the nasal cavity?
The nasal septum.
What are the main components of the skeleton of the external nose?
Several bones and cartilages.
What additional arteries supply the external nose?
Nasal branches of the infra-orbital artery and lateral nasal branches of the facial artery.
Which nerve supplies the anterosuperior portion of the nasal mucosa?
The ophthalmic nerve (CN V1) via the anterior and posterior ethmoidal nerves.
Which nerve supplies the alae of the nose?
The nasal branches of the infra-orbital nerve (CN V2).
What does the anterior end of the hiatus semilunaris lead into?
A funnel-shaped channel called the infundibulum.
Which divisions of the trigeminal nerve provide general sensation to the nasal cavity?
The ophthalmic division (V1) and the maxillary division (V2).
What forms the anterior roof of the nasal cavity?
The nasal and frontal bones.
What is the function of the superior one third of the nasal mucosa?
It serves as the olfactory area, containing the peripheral organ of smell.
What role does sniffing play in the olfactory area?
Sniffing draws air to the olfactory area for smell detection.
How is the nasal mucosa divided in terms of nerve supply?
Into postero-inferior and anterosuperior portions by an oblique line.
What forms the superior part of the nasal septum?
The thin perpendicular plate of the ethmoid bone.
What is a clinical correlation of emissary veins?
They are routes by which infections can track from peripheral regions into the cranial cavity.
What are the primary muscles of the external nose?
Nasalis (compressor naris), dilator naris, and levator labii superioris alaeque nasi.
What is the most common cause of nosebleeds?
Trauma.
Which part of the nasal septum is formed by contributions from the maxillary and palatine bones?
The vomer forms the postero-inferior part of the nasal septum with contributions from the nasal crests of these bones.
What are the main structural components of each half of the nasal cavity?
Roof, floor, lateral wall, and medial wall.
Which artery supplies the posterior part of the nasal cavity?
Posterior ethmoidal artery.
Which artery reaches the nasal septum via the incisive canal?
Greater palatine artery.
Which artery provides blood supply to the nasal septum from the facial artery?
Septal branch of the superior labial artery.
What does the additional nasal vein connect to?
The anterior end of the superior sagittal sinus.
What are emissary veins?
Veins that connect an intracranial venous sinus with extracranial veins.
What does the superior meatus receive?
The openings of the posterior ethmoid sinuses.
What conditions are associated with epistaxis?
Infections and hypertension.
What are the two main sources of arterial supply to the nasal cavity?
Internal and external carotid arteries.
What are the boundaries of the nasal cavity?
It extends from the nostrils in front to the posterior nasal apertures (choanae) behind.
What is the inferior concha?
An individual bone.
What is the shape of the alar cartilages?
U-shaped.
What is the hiatus semilunaris?
A curved opening just below the bulla ethmoidalis.
What causes spurting of blood from the nose?
Rupture of arteries.
What divides the nasal cavity into right and left halves?
The nasal septum.
What are the three projections of bone found on the lateral wall of the nasal cavity?
Superior, middle, and inferior nasal conchae.
Which artery supplies the anterior part of the nasal cavity?
Anterior ethmoidal artery.
What do veins draining the nasal cavities generally follow?
The arteries.
What bones are the superior and middle conchae part of?
The ethmoid bone.
What does the sphenoethmoidal recess receive?
The opening of the sphenoid air sinus.
What are the three types of meatus in the nasal cavity?
Superior, middle, and inferior meatus.
What is the bulla ethmoidalis?
A rounded swelling in the middle meatus formed by the middle ethmoidal air sinuses.
Which nerve innervates the primary muscles of the external nose?
The facial nerve (CN VII).
Where do most cases of anterior epistaxis originate?
From the Kiesselbach plexus on the nasal septum.
What is located in the middle of the roof of the nasal cavity?
The cribriform plate of the ethmoid.
What are the components of the floor of the nasal cavity?
The palatine process of the maxilla and the horizontal plate of the palatine bone.
What forms the anterior part of the nasal septum?
The septal cartilage.
What divides the nasal cavity into right and left halves?
The nasal septum.
What are the main components of the nasal septum?
Perpendicular plate of the ethmoid, vomer, and septal cartilage.
What arteries supply the skin of the external nose?
Branches of the ophthalmic and maxillary arteries, and branches from the facial artery.
What does the inferior meatus receive?
The opening of the lower end of the nasolacrimal duct.
How are the blood vessels of the nasal septum related to epistaxis?
They can be involved in nosebleeds due to their location and fragility.
What is the atrium in the nasal cavity?
The entrance to the middle meatus, sitting just superior to the vestibule.
What does the nasal septum divide?
The chamber of the nose into two nasal cavities.
How does the septal cartilage articulate with the bony septum?
It has a tongue-and-groove articulation with the edges of the bony septum.
Why is epistaxis relatively common?
Due to the rich blood supply to the nasal mucosa.
What is anterior epistaxis?
Nosebleed that originates from the anterior part of the nose.
What supplies most of the external nose, including the dorsum and apex?
The ophthalmic nerve (CN V1) via the infratrochlear nerve and the external nasal branch of the anterior ethmoidal nerve.
Where do the olfactory nerves arise from?
From cells in the olfactory epithelium in the superior part of the nasal cavity.
What can cause mild epistaxis?
Nose picking, which tears veins in the vestibule of the nose.
What do the central processes of olfactory cells form?
The olfactory nerve, which passes through the cribriform plate to the olfactory bulb.
From which area does most nosebleeding occur?
The anterior third of the nose (Kiesselbach area).
What is the lateral margin of the external nose called?
Ala nasi.
What are the two main components of the nose?
The external nose and the nasal cavity.
How does the external nose attach to the forehead?
By the root (bridge) of the nose.
What are the key features to identify on the lateral wall of the nasal cavity?
Specific structures can vary, but typically include turbinates and meatuses.
What are the external openings of the nose called?
Nostrils (nares).
