Anatomy of the Nose and Sinuses

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Questions and Answers

What is the function of the nasal conchae?

To allow drainage of the paranasal sinuses

To facilitate the sense of smell

To filter and humidify inhaled air (correct)

To provide structural support to the nose

Which paranasal sinus drains into the superior meatus?

Maxillary Sinus

Sphenoid Sinus

Frontal Sinus

Posterior Ethmoid Cells (correct)

Which nerve is responsible for the sensory innervation of the superior part of the nasal cavity?

Trigeminal Nerve (V1) (correct)

Olfactory Nerve (CN I)

Facial Nerve (CN VII)

Glossopharyngeal Nerve (CN IX)

What makes up the nasal septum?

Perpendicular plate of the ethmoid bone and vomer bone Signup and view all the answers

Where are the frontal sinuses located?

Above the eyes in the frontal bone Signup and view all the answers

What type of epithelium is found in the nasal mucosa?

Pseudostratified ciliated columnar epithelium Signup and view all the answers

Which type of drainage do the maxillary sinuses have?

Drain into the middle meatus Signup and view all the answers

What is the primary function of goblet cells in the nasal mucosa?

To produce mucus Signup and view all the answers

What type of innervation does the maxillary division (V2) provide?

Sensory innervation to the inferior part of the nasal cavity Signup and view all the answers

Which cranial nerve carries parasympathetic fibers to the nasal and palatine glands?

Facial nerve (CN VII) Signup and view all the answers

Which fibers are responsible for vasoconstriction in the nasal cavity?

Sympathetic fibers from the superior cervical ganglion Signup and view all the answers

Which sinus drains into the middle meatus of the nasal cavity?

Maxillary sinuses Signup and view all the answers

What is the source of the sympathetic fibers that innervate the nasal cavity?

Superior cervical ganglion Signup and view all the answers

What type of innervation do the olfactory nerves provide?

Sensory innervation to the nasal cavity Signup and view all the answers

Which division of the trigeminal nerve provides sensory innervation to the nasal cavity?

Both V1 and V2 Signup and view all the answers

Which structure does NOT have a defined innervation source according to the summary table?

External Nose Signup and view all the answers

Study Notes

Anatomy of the Nose

The external nose is composed of the nasal bones, cartilage, and skin. It includes the root (area between the eyes), bridge (top portion), apex (tip), and nostrils (external openings).
The internal nose is divided by the nasal septum into left and right cavities. The septum is made up of the perpendicular plate of the ethmoid bone, vomer bone, and septal cartilage.
Nasal conchae (turbinates) are bony structures covered by mucosa that increase the surface area for warming and humidifying inhaled air. There are three conchae: superior, middle, and inferior.
Meatuses are spaces below each concha (superior, middle, and inferior) that drain the paranasal sinuses and nasolacrimal duct.
The nasal mucosa is lined with pseudostratified ciliated columnar epithelium containing goblet cells, which help warm, moisten, and filter inhaled air.

Paranasal Sinuses

Paranasal sinuses are air-filled cavities located within the frontal, maxillary, ethmoid, and sphenoid bones, which open into the nasal cavity.
Frontal sinuses are located above the eyes in the frontal bone and drain into the middle meatus.
Maxillary sinuses are located in the maxillary bones below the eyes and drain into the middle meatus.
Ethmoid sinuses are located between the eyes within the ethmoid bone. Anterior ethmoid cells drain into the middle meatus, while posterior ethmoid cells drain into the superior meatus.
Sphenoid sinuses are located in the sphenoid bone behind the ethmoid sinuses. They drain into the sphenoethmoidal recess, located above the superior concha.

Innervation of the Nose and Paranasal Sinuses

Sensory innervation
- Olfactory nerve (CN I) provides the sense of smell, with olfactory fibers passing through the cribriform plate of the ethmoid bone.
- Trigeminal nerve (CN V) provides sensory innervation:
  - V1 (Ophthalmic division): Innervates the superior part of the nasal cavity via the nasociliary nerve
  - V2 (Maxillary division): Innervates the inferior part of the nasal cavity and the paranasal sinuses via nasal branches of the maxillary nerve.
Parasympathetic innervation
- Facial nerve (CN VII): The greater petrosal nerve (branch of CN VII) carries parasympathetic fibers to the pterygopalatine ganglion. Postganglionic fibers then innervate the nasal and palatine glands.
Sympathetic innervation
- Sympathetic fibers originating from the superior cervical ganglion travel with the internal carotid artery to the nasal cavity and sinuses. They are involved in vasoconstriction.

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Description

Explore the structure and function of the external and internal aspects of the nose, including the nasal conchae, septum, and mucosa. This quiz covers both the anatomy of the nose and the associated paranasal sinuses, providing a comprehensive overview of respiratory anatomy.