nasal cavities and paranasal sinuses

Question 1

external nose landmarks

Answer 1

• root
• dorsum
• apex
• ala
• nares
• philtre of upper lip

Question 2

nose is made up from

Answer 2

the nasal bone and nasal cartilage

Question 3

external nasal skeleton

Answer 3

nasal bone and maxillary bone

Question 4

the nasal septum

Answer 4

the vomer, perpendicular plate of the ethmoid bone, cartilage

Question 5

roof of ethmoid bone

Answer 5

• cribriform plate of ethmoid bone (contains openings fro the olfactory nerves to pass through)
• crista gall (provides anterior attachment for the fall cerebri)

Question 6

lateral walls of the ethmoid bone

Answer 6

• superior nasal conchae
• middle nasal conchae
• orbital plate of ethmoid bone
• ethmoid cells

Question 7

inferior nasal conchae

Answer 7

is a bone in itself

Question 8

le fort fractures

Answer 8

• le fort I= floating palate
• le fort II= floating maxilla
• le fort III= floating face

Question 9

le fort II and III fractures

Answer 9

can disrupt the cribriform plate of the ethmoid bone, so there is danger of infection spreading between the nasal cavity/ paranasal sinuses into the anterior cranial fossa

Question 10

walls of the nasal cavities

Answer 10

• lateral wall contains= superior middle and inferior nasal conchae
• medial wall= vomer, perpendicular plate of ethmoid bone, septal cartilage

Question 11

mucosa of nasal cavities

Answer 11

1. Keratinised stratified squamous epithelium
2. Respiratory epithelium
3. Olfactory mucosa

Question 12

respiratory epithelium secretes

Answer 12

mucous

Question 13

olfactory nerve

Answer 13

RECEPTOR CELLS= present in the olfactory mucosa and are the list neutrons in the chain, pass through the cribriform plate of the ethmoid bone
OLFACTORY BULB= ganglion which contains the cell bodies of the 2nd neutron
OLFACTORY TRACTS= ends in temporal lobe

Question 14

general sensory supply to the lateral wall and the septum

Answer 14

anterosuperiorly= CN V1 
posteroinferiorly= CN V2

Question 15

blood supply

Answer 15

external carotid artery gives of the facial and maxillary arteries
internal carotid artery gives of the opthalmic artery

Question 16

blood supply of the medial wall (IE THE SEPTUM)

Answer 16

• the internal carotid artery gives off the opthalmic aftery which gives of the anterior and posterior ethmoidal arteries which supply the superior part of nasal septum
• the external carotid artery gives off the maxillary artery and facial artery
• the maxillary artery gives off the sphene-palatine and greater palatine artery which supply the postern-inferior septum
• the facial artery gives off the labral branch which supplies the anteroinferior septum

Question 17

littles area is the anastomosis between

Answer 17

the anterior ethmoidal artery the greater palatine artery the sphenopalatine artery and the labral branch nut NOT the posterior ethmoidal artery

Question 18

blood supply to the lateral wall

Answer 18

is the exact same but the maxillary artery from the external carotid artery splits into 3 main branches to supply the posteroinferior part:

• greater palatine
• spheno palatine
• leser palatine

Question 19

important area

Answer 19

KIESSELBACKS AREA (LITTLEBACKS AREA)= arterial anastomosis on the nasal septum which is the most common place for epistaxis

Question 20

nasal conchae function

Answer 20

regulate airflow through the nasal passages and they increase the surface area of the nasal cavity and warm air passing through

Question 21

what is under the nasal conchae

Answer 21

meatuses are the spaces under each conchae:

superior middle and inferior meatus

Question 22

what is above the superior nasal conchae

Answer 22

sphenoethmoidal recess

Question 23

inserting a NG tube

Answer 23

passes through the inferior nasal conchae (sensory innervation CN V2) and through the nano-, oro- and laryngopharynx into the oesophagus

Question 24

summary of nasal cavities

Answer 24

• act as a patent conduit for air passing into the nasopharynx
• filters particles via vibriossae (small hairs)
• humidifies air
• warms inspired air
• sense of smell as air passes over olfactory epithelium

Question 25

paranasal sinuses are

Answer 25

air filled spaces within bone

Question 26

the paranasal sinuses are

Answer 26

• 2 frontla sinuses
• 2 sphenoid sinuses
• 2 ethmoid air cells
• 2 maxillary sinuses (clinically called the mantra)

Question 27

the paranasal sinuses are

Answer 27

lined with mucous secreting respiratory epithelium, the mucous drains into the nasal cavity via OSTIA in the lateral walls of the nasal cavities

Question 28

frontal sinus drains into

Answer 28

middle meatus

Question 29

ethmoid air cells drain into

Answer 29

superior and middle meatus

Question 30

sphenoid sinus drains into

Answer 30

sphenoethmoidal recess

Question 31

maxillary sinus drains into

Answer 31

middle meatus

Question 32

sinusitis

Answer 32

inflammation of the mucosa of the paranasal sinuses

Question 33

why is sinusitis painful

Answer 33

because sensory innervation via CN V1 and CN V2

Question 34

where can sinusitis pain be referred

Answer 34

teeth

Question 35

most commonly affected sinus

Answer 35

maxillary

Question 36

why is maxillary sinus the most commonly affected

Answer 36

because the ostia of the maxillary sinus is located superiorly so it has to drain against gravity

Question 37

extraction of a tooth could cause

Answer 37

an oro-astral fistula so the roots of the teeth can spread infection into the maxillary sinus

Question 38

why might maxillary sinusitis present as toothache

Answer 38

because the maxilla, mandible, mucosa of maxillary

sinus, and the teeth all are innervated by the trigeminal nerve