Nose and Nasal Cavity

Question 1

Anterolateral view of nasal cavities

Answer 1

Question 2

Structures within nasal cavities

Answer 2

Question 3

What are the anterior apertures called

Answer 3

Nares - open onto inferior surface of the nose

Question 4

What are the posterior apertures called

Answer 4

Choanae, which open into the nasopharynx

Question 5

How are the nasal cavities separated

Answer 5

From each other by a midline nasal septum

From the oral cavity below by the hard palate

From the cranial cavity above by parts of the frontal, ethmoid and sphenoid bones

Question 6

What do the conchae do

Answer 6

Increase SA of contact between tissues of the lateral wall and respired air

Question 7

Openings into nasal cavity

Answer 7

Question 8

Regions of the nasal cavity

Answer 8

Question 9

What is the nasal vestibule

Answer 9

A small dilated space just internal to the naris that is lined by skin and contains hair follicles

Question 10

RESP REGION

1. Neurovascular supply
2. Lined with…
3. Composed of

Answer 10

1. Rich neurovascular supply
2. Lined by respiratory epithelium
3. Composed mainly of ciliated and mucous cells

Question 11

OLFACTORY REGION

1. Lined with
2. What does it contain

Answer 11

1. Lined by olfactory epithelium
2. Contains the olfactory receptors

Question 12

Other than housing receptors for smell (olfaction), name 2 other functions of nasal cavities

Answer 12

1. Adjust temperature and humidity of respired air by the action of a rich blood supply
2. trap and remove particulate matter from the airway by filtering the air through hair in the vestibule and by capturing foreign material in abundant mucus (which is then moved posteriorly by cilia on epithelial cells in the nasal cavities and is swallowed)

Question 13

General sensation of the nasal cavities

Answer 13

Trigeminal nerve (V)

Question 14

Innervation of anterior region

Answer 14

Ophthalmic nerve (V1)

Question 15

Innervation of posterior region

Answer 15

Maxillary nerve (V2)

Question 16

What are all glands innervated by

Answer 16

Parasympathetic fibres in the facial nerve (VII), which join branches of the maxillary nerve (V2) in the pterygopalatine fossa

Question 17

Where are the sympathetic fibres of the nasal cavities derived from

Answer 17

T1 spinal cord level

Question 18

Where do the sympathetic fibres of the nasal cavities synapse

Answer 18

Mainly in the superior cervical sympathetic ganglion

Question 19

How do postganglionic fibres reach the nasal cavities

Answer 19

Along blood vessels or by joining branches of the maxillary nerve (V2) in the pterygopalatine fossa

Question 20

Blood supply to the nasal cavities

Answer 20

1. Terminal branches of the maxillary and facial arteries, originating from the external carotid artery
2. Ethmoidal branches of the ophthalmic artery, originating from the internal carotid artery

Question 21

Ethmoid bone

Answer 21

Question 22

What does the crista galli anchor

Answer 22

A fold of dura mater, falx cerebri, in the cranial cavity

Question 23

What does the perpendicular plate of the ethmoid bone articulate with

Answer 23

1. POSTERIORLY - Sphenoidal crest on the body of the sphenoid bone and vomer
2. ANTERIORLY - nasal spine on frontal bone and with the site of articulation at the midline between the 2 nasal bones
3. INFERIORLY AND ANTERIORLY - septal cartilage

Question 24

External nose

Answer 24

Question 25

Medial wall of the nasal cavity - the nasal septum

Answer 25

Question 26

Floor of the nasal cavity

Answer 26

Question 27

Roof of nasal cavity

Answer 27

The nares is formed by the lateral processes of the septal cartilage and major alar cartilages of the external nose Nasal spine of the frontal bone and nasal bones

Question 28

What is the choana formed by

Answer 28

Anterior surface of the sphenoid bone Ala of the vomer and adjacent sphenoidal process of the palatine bone Vaginal process of the medial plate of the pterygoid process

Question 29

Lateral wall of the nose

Answer 29

Question 30

Where does the nasolacrimal duct open onto

Answer 30

Lateral wall of the inferior nasal meatus under the anterior lip of the inferior concha

Question 31

Where does the frontal sinus drain

Answer 31

Via frontonasal duct and ethmoidal infundibulum into the anterior end of the semilunar hiatus on the lateral wall of the middle nasal meatus

Question 32

Where do the anterior ethmoidal cells drain into

Answer 32

Frontonasal duct or ethmoidal infundibulum (in some cases, the frontal sinus drains directly into the anterior end of the middle nasal meatus and the frontonasal duct ends blindly in the anterior ethmoidal cells)

Question 33

Where do the middle ethmoidal cells open onto

Answer 33

Ethmoidal bulla

Question 34

Where do the posterior ethmoidal cells open onto

Answer 34

Lateral wall of the superior nasal meatus

Question 35

Where does the large maxillary sinus open into

Answer 35

Semilunar hiatus, usually just inferior to the centre of the ethmoidal bulla (opening is near the roof of the maxillary sinus)

Question 36

Where does the sphenoidal sinus open onto

Answer 36

Posterior roof of nasal cavity

Question 37

Structure of nares

Answer 37

Question 38

Structure of choanae

Answer 38

Question 39

Gateways to the nasal cavity

Answer 39

* Fibres of olfactory nerve (I) pass through the cribriform plate * Small foramina between the cribriform plate and surrounding bone allow the anterior ethmoidal nerve (branch of ophthalmic nerve - V1) and accompanying vessels to pass from the orbit into the cranial cavity and then down into the nasal cavity * There is a connection in some individuals between nasal veins and the superior sagittal sinus of the cranial cavity through a prominent foramen (foramen cecum) in the midline between the crista galli and frontal bone

Question 40

1. The sphenopalatine foramen is a route of communication between what structures 2. What are the major structures passing through the foramen

Answer 40

1. Nasal cavity and pterygopalatine fossa 2. Sphenopalatine branch of maxillary artery, Nasopalatine branch of maxillary nerve (V2), superior nasal branches of the maxillary nerve (V2)

Question 41

What do the incisive canals (opening into the incisve fossa) transmit

Answer 41

Nasopalatine nerve from the nasal cavity into oral cavity Terminal end of greater palatine artery from oral cavity into nasal cavity

Question 42

What do small foramina in the lateral wall transmit

Answer 42

1. Internal nasal branches of the infra-orbital nerve of the maxillary nerve [V2] and alar branches of the nasal artery from the facial artery 2. Inferior nasal branches from the greater palatine branch of the maxillary nerve [V2]

Question 43

Why is the submucosa of the resp region (particularly that related to the conchae and septum) described as 'erectile' or 'cavernous'

Answer 43

Tissue enlarges or shrinks depending on the amt of blood flowing into the system

Question 44

Arterial supply of the nose

Answer 44

Question 45

Venous drainage of the nose

Answer 45

In some individuals, an additional nasal vein passes through the foramen cecum in the frontal bone anterior to the crista galli and joins with the anterior end of the superior sagittal sinus Because this nasal vein connects an intracranial venous sinus with extracranial veins, it is classified as an emissary vein - routes by which infections can track from peripheral regions into the cranial cavity (Veins that accompany the ant and post ethmoidal arteries are tributaries of the superior ophthalmic vein, which is 1 of the largest emissary veins and drains into the cavernous sinus on either side of the hypophyseal fossa)

Question 46

Innervation of the nose 1. 2 branches of the ophthalmic nerve - V1 2. Branches from the maxillary nerve - V2

Answer 46

1. Anterior and posterior ethmoidal nerves 2. Nasal nerves (MANY!)

Question 47

Lymphatics of the nose

Answer 47

ANTERIOR Drain forward onto the face by passing around the margins of the nares and then ultimately connect with the submandibular nodes POSTERIOR Lymph from posterior regions of the nasal cavity and the paranasal sinuses drain into upper deep cervical nodes (some first passes through the retropharyngeal nodes)