Nasal Cavities And Paranasal Sinuses

Front 1

What are the three regions of each nasal chamber?

Back 1

vestibule
respiratory segment
olfactory segment

Front 2

What is the vestibule?

Back 2

Site of communication with external environment via the external nares (nostrils).

Front 3

What is the histology of the vestibule?

Back 3

Lined with stratified squamous epithelium that contains hairs.
Hairs prevent large particulates from entering the nasal cavities.

Front 4

What transition area is seen at the end of the vestibule?

Back 4

Where the vestibule ends, the stratified squamous epithelium is replaced by respiratory epithelium, pseudostratified columnar ciliated epithelium with goblet cells.

Front 5

What is the histology of the respiratory segment?

Back 5

Lined by pseudostratified columnar ciliated epithelium with goblet cells (respiratory epithelium).

Underlying lamina propria attached to the periosteum of the underlying bone.

Front 6

What are the boundaries of the respiratory segment?

Back 6

The medial wall is nasal septum.

The lateral wall is characterized by three shelf-like bony prominences call conchae or turbinates.

Front 7

What is the function of the turbinates?

Back 7

They increase surface area and cause a turbulence in air flow to allow for better warming and moisterizing of the air.

The turbinates also cause eddies in the airflow that help remove particulate matter by trapping it in the mucus of the cavity.

Front 8

What happens to the LP of the nasal cavity during an allergic reactoin?

Back 8

Vessels become excessively engorged and leaky during allergic reactions and viral infections.

consequent distention of the lamina propria makes breathing more difficult.

Front 9

What is the function of the LP of the nasal cavity?

Back 9

Very vascular.

Warms the inspired air nearer to body temperature.

Front 10

What do demilume cells do?

Back 10

Demilune cells secrete lysozyme, an antibacterial.

Front 11

What is the olfactory segment?

Back 11

Although the olfactory epithelium is pseudostratified columnar epithelium similar in appearance to respiratory epithelium, it is actually very different.

A very effective few square centimeters.

Front 12

What are the 4 cell types in the olfactory segment?

Back 12

Olfactory cells
Special visceral sensory cells

Supporting or sustentacular cells
Provide mechanical and metabolic support for olfactory sensory cells. Role is similar to that of glial cells.

Basal cells
Mitotic cells that renew the sensory and sustentacular (supporting) cells.

Brush cells
General sensory cells - innervated by the trigeminal nerve (cranial nerve V).
Signal touch from the olfactory epithelium. Brush cells are also found in the respiratory epithelium

Front 13

What are the olfactory cells?

Back 13

At their apical surface, they have a knob-like structure, the olfactory vesicle.
Bipolar neurons

The vesicle has a number of non-motile cilia on its surface. The cilia are the sites of olfactory receptors.

Front 14

What does the basal end of the olfactory cell do?

Back 14

The basal end of the cell gives rise to an axon.

The axon joins others to form the olfactory nerve (cranial nerve I).

Front 15

Where do the olfactory cell axons go?

Back 15

The olfactory axons penetrate the cribiform plate of the ethmoid bone to synapse in the olfactory bulb.

These neurons, unlike others in adult humans, can regenerate.

Front 16

What is the framework of the nasal cavity?

Back 16

External nose predominantly cartilagenous.

Posterior nasal cavity predominantly bone.

Front 17

What are the posterior openings into the nasopharynx?

Back 17

Choana

Front 18

What are the components of the nasal septum?

Back 18

Septal cartilage,
Vomer.
Perpendicular plate of the ethmoid bone.
Small contribution by the nasal bones
nasal spine of the frontal bone.
Nasal crests of the maxillary and palatine bones.
Rostrum of sphenoid bone incisor crest of the maxilla.

Front 19

What does the ethmoid bone contribute to the nasal cavity?

Back 19

Cribriform plate is the roof. Highest part of the nasal cavity.

Front 20

What rests on the cribriform plate?

Back 20

Olfactory bulb

Front 21

What goes through the cribriform foramina?

Back 21

Olfactory nerves

Front 22

What makes up the roof of the nasal cavity?

Back 22

nasal spine of frontal bone
Nasal bone
Lateral processes of septal bone.
Major alar cartilages.

Front 23

What makes up the floor of the nasal cavity

Back 23

Soft tissue of external nose.
Upper surface of the hard palate.
Palatine process of maxillary bone.
Horizontal plate of palatine bone.

Front 24

What makes up the lateral wall of the nasal cavity?

Back 24

Ethmoid bone. - Labyrinth and uncinate process.
Palatine bone.- Perpendicular plate.
Sphenoid bone. - Medial plate of pterygoid process.
Lacrimal bone. - Medial surface.
Maxillary bone. - Medial surface.
Inferior concha. - Separate bone.

Front 25

What are the four paired paranasal air sinuses?

Back 25

Frontal.
Ethmoidal air cells. - Anterior. Middle. Posterior.
Maxillary.
Sphenoidal

Front 26

Where do the paranasal sinuses drain into?

Back 26

Nasal cavities

Front 27

What are the sinuses lined by?

Back 27

Olfactory epithelium, there is a lining under the bone

Front 28

What can you see in a CT of normal sinuses?

Back 28

MS –maxillary sinus

ES – ethmoid sinuses

SC – superior choncha

MC – middle choncha

IC – inferior choncha

Front 29

Where does the frontal sinus drain?

Back 29

Frontal sinus drains via the frontonasal duct into the middle meatus.

Front 30

Where does the anterior ethmoid air cells drain?

Back 30

Anterior drains into frontonasal duct or infundibulum.

Front 31

Where do the middle ethmoid sinus drain?

Back 31

Middle drain onto the ethmoidal bulla.

Front 32

Where does the posterior ethmoid sinus drain?

Back 32

Posterior drain onto lateral wall of superior meatus.

Front 33

Where does the maxillary sinus drain?

Back 33

Maxillary drains into semilunar hiatus.

Front 34

Where does the sphenoidal sinus drain?

Back 34

Sphenoid sinus drains into spheno-ethmoidal recess.

Front 35

What are the frontal sinuses innervated by?

Back 35

Innervated by branches of the supraorbital nerve of V1.

Front 36

What are the ethmoidal sinuses innervated by?

Back 36

Branches of nasociliary from V1 and orbital branches of V2 from pterygopalatine ganglion.

Front 37

What are the maxillary sinuses innervated by?

Back 37

Infraorbital and alveolar branches of V2.

Front 38

What are the sphenoidal sinuses innervated by?

Back 38

Posterior ethmoidal branch of V1 and orbital branches of V2 from pterygopalatine ganglion.

Front 39

What are the two branches of the sphenopalatine?

Back 39

Posterior lateral nasal
Posterior septal

Front 40

What is the main blood supply of the nasal cavity?

Back 40

Sphenopalatine artery

Front 41

What is the course of the greater palatine artery?

Back 41

Travels from pterygopalatine fossa, through the greater palatine foramen, along roof of oral cavity and enters nasal cavity via the incisive foramen.

Front 42

What is the course of the anterior ethmoidal artery?

Back 42

Enters nasal cavity via a foramen immediately lateral to crista galli of the ethmoid bone.

Branch to the septum.
Lateral branch.

Front 43

What does the posterior ethmoidal artery supply?

Back 43

Upper posterior lateral wall and septum.

Front 44

Where does the majority of the nasal cavity drain?

Back 44

Much of the blood from the nasal cavity drains posteriorly into the pterygopalatine plexus or the cavernous sinus.

Front 45

What enters the nasal cavity via the sphenopalatine foramen?

Back 45

Nasopalatine nerve
Posterior superior lateral
Posterior superior medial nerves.

Front 46

What is a branch of the greater palatine nerve that passes through small bony foramina to enter the nasal cavity?

Back 46

Posterior inferior alveolar nerves

Front 47

What are the branches of V2 that innervate the nasal cavity?

Back 47

Nasopalatine nerve
Posterior superior lateral
Posterior superior medial
Posterior inferior aveolar

Front 48

What are the branches of V1 nasocilliary that innervate the nasal cavity?

Back 48

Anterior ethmoidal nerve.
Posterior ethmoidal nerve.

Front 49

What are the three major innervations of the nasal cavity?

Back 49

Olfactory
V1 --> nasociliary branches
V2 --> from pterygopalatine fossa

Front 50

What are the parasympathetics to the nasal cavity?

Back 50

Preganglionic axons are in greater petrosal nerve of facial nerve

Postganglionic neurons are in the pterygopalatine ganglion. - These secretomotor axons travel with branches of V that enter the nasal cavity and paranasal sinuses.

Front 51

What are the sympathetics to the nasal cavity?

Back 51

Preganglionic neuron at T1 level of spinal cord. - Synapse in superior cervical ganglion.

Postganglionic axons travel in the carotid plexus. - Form deep petrosal nerve, which joins greater petrosal nerve to form the nerve of the pterygoid canal.
Travel with parasympathetics in branches of V.

These axons are vasomotor.

Front 52

Where does the nasolacrimal duct drain?

Back 52

Into the inferior meatus

Front 53

What are the cartilages of the external nose?

Back 53

Lateral process of septal cartilage
Superior margin of septal cartilage
Major alar cartilage (tip of nose)
Septal cartilage (bottom of nose)
Minor alar cartilages (back of nostril)

Front 54

What is the ethmoidal bulla?

Back 54

The rounded portion made by the middle ethmoidal cells

Front 55

What tube opens in the back of the nasal cavity?

Back 55

Pharyngotympanic tube

Front 56

What is the semilunar hiatus?

Back 56

Area where the infundibulum of frontonasal duct and the ethmoidal bullus is.

Under the middle nasal concha

Front 57

Where does the maxillary sinus drain?

Back 57

In the opening of the floor of the semilunar hiatus

Front 58

Where is the lateral wall of the superior meatus located?

Back 58

Under the superior nasal concha

Front 59

What artery goes all the way along the roof of the oral cavity?

Back 59

Greater palatine artery

Front 60

Where does the nasolacrimal duct drain?

Back 60

Into the inferior meatus below the inferior concha

Front 61

Parts of the lacrimal apparatus

Back 61

Puncta
Lacrimal canaliculi
Lacrimal sac
Nasolacrimal duct