Paranasal Sinuses

Question 1

External nose

Bones and cartilage

Answer 1

• Root of nose 3 bones
  
  • Frontal
  • Maxilla
  • Nasal
• Dorsum and apex of nose, 3 hyaline cartilages
  
  • Septal
  • Lateral nasal
  • Alar

Question 2

Nasal Cavity Boundaries

Floor and roof

Answer 2

• Floor
  
  • Hard palate
    
    • Palatine process of maxilla
    • Horizontal plates of palatine bone
• Roof
  
  • Cribriform plate,
  • sphenoid,
  • frontal,
  • nasal,
  • lateral nasal cartilages

Question 3

Nasal cavity boundaries

Lateral wall

medial wall

external nose

Answer 3

• Lateral wall
  
  • Nasal
  • Ethmoid
  • Sphenoid
  • Maxilla
  • Palatine
  • Inferior nasal conchae
• Medial wall
  
  • Nasal septum
• External nose
  
  • 2 nasal bones and nasal cartilages

Question 4

Nasal Conchae

Answer 4

• Superior nasal conchae, middle nasal conchae
  
  • Ethmoid bone
• Inferior nasal conchae

Question 5

Nasal Meatuses

Answer 5

• Sphenoethmoidal recess
• Superior meatus
• Middle meatus
• Inferior meatus

Question 6

Regions of Nasal Cavities

Answer 6

• Nasal vestibules
  
  • Nares
• Respiratory regions
  
  • Openings between nasal cavities and nasopharynx
• Olfactory regions
  
  • CN I

Question 7

Olfaction

Answer 7

• Olfactory neurons
  
  • Chemoreceptors, Bipolar neurons
• Supporting cells
• Basal cells
  
  • Stem cells for renewal of other cells
• Project to primary olfactory cortex

Question 8

Innervation of Nasal cavities

3

Answer 8

• Olfaction
  
  • Olfactory nerve CN I
• General sensation
  
  • CN V1 and CN V2
    
    • Anterior ethmoid of V1
    • Nasopalatine, infraorbital, greater palatine of V2
• Parasympathetic
  
  • CN VII
  • Greater petrosal via pterygopalatine ganglion
• Sympathetic
  
  • from T1 via superior cervical ganglion

Question 9

Arterial supply to Nasal Cavities

Answer 9

• Terminal branches of Maxillary and facial (ECA)
  
  • Sphenopalatine, Greater palatine
  • Superior labial
  • Lateral nasal
• Branches of opthalmic a (ICA)
  
  • Dorsal nasal
  • Ant and post ethmoidal
• ECA and ICA anastosome on nose

Question 10

Venous drainage of nasal cavities

Answer 10

• Veins passing with Max arteries drain into pterygoid plexus in the infratemporal fossa
• Veins from anterior region of nasal cavities join the facial vein

Question 11

Lymphatics of Nasal cavities

Ant and post regions

Answer 11

• Anterior region
  
  • submandibular nodes
• Posterior region
  
  • Deep cervical nodes, retropharyngeal nodes

Question 12

Nasal septum

Composed of 5

Answer 12

• Perpendicular plate of ethmoid bone
• Vomer
• Cartilage of septum
• Crest of maxillary
• Crest of palatine

Question 13

Nasal cavity gateways and what travels through them

Foramen cecum

Cribriform plate

Sphenopalatine plate 3

Incisive 2

Answer 13

• Foramen cecum
  
  • Emissary veins (connect cavernous sinus and pterygoid plexus)
• Cribriform plate
  
  • CN I
• Sphenopalatine formen
  
  • Superior nasal meatus
  • Sphenopalatine a.
  • V2- Nasopalatine and Nasal
• Incisive
  
  • Greater palatine artery
  • Nasopalatine V2

Question 14

Nasal cavity gateways

Small lateral wall foramina

Nares 2

Answer 14

• Small lateral wall foramina
  
  • Greater palatine n nasal branches of V2
• Nares
  
  • Infra orbital nerve of V2 nasal branches
  • Alar nerve

Question 15

4 Paranasal sinuses

Histo

Innervation

Answer 15

• Ethmoid air cells
• Sphenoid sinuses
• Maxillary sinuses (first to develop)
• Frontal sinuses
• Lined by respiratory mucosa, cilliated, and mucous secreting
• Open into nasal cavities
• Innervated by CN 5 branches

Question 16

Paranasal sinus drainage

Answer 16

Paranasal sinus and nasolacrimal drain into nasal cavities

Question 17

Frontal sinuses

Superior

Inferior

Anterior

Posterior

Medial

Answer 17

• Superior
  
  • anterior cranial fossa
• Inferior
  
  • orbit, ethmoidal sinuses, nasal cavity
• Anterior
  
  • Forehead, superciliary arches
• Posterior
  
  • Anterior cranial fossa
• Medial
  
  • Other frontal sinuses

Question 18

Frontal sinuses

drainage

Innervation

Answer 18

• Middle meatus
  
  • via frontonasal dusct and semilunar haitus
• Innervation
  
  • V1
    
    • Supraorbital n. and supratrochlear

Question 19

Frontal nasal

Arterial supply 3

Lymphatics

Answer 19

• Arterial supply
  
  • Anterior ethmoid
  • Supraorbital
  • supratrochlear
  • (From ICA of opthalmic)
• Lymphatics
  
  • Submandibular nodes

Question 20

Ethmoid air cells

Drainage

Innervation 2

Answer 20

• Drain
  
  • Posterior ethmoid into superior meatus
  • Anterior and middle ethmoid into meatus
• Innervation V1
  
  • Anterior ethmoid
  • Post ethmoid

Question 21

Ethmoidal sinus

Arterial supply 3

Lymphatics 2

Answer 21

• Arterial supply
  
  • ICA
    
    • Anterior and posterior ethmoid
  • ECA
    
    • Posterior lateral nasal branches of sphenopalatine a.
• Lymphatics
  
  • Submandibular nodes
  • retropharyngeal nodes

Question 22

Spenoid Sinus

drain

innervtion

arterial

lymphatics

Answer 22

• Drain
  
  • Sphenoethmoidal recess
• Innervation
  
  • Post ethmoid n, V1
• Arterial supply
  
  • ICA–> Post ethmoid a.
  • ECA–> Pharyngeal a.
• Retropharyngeal nodes

Question 23

Maxillary sinus relations

Superior

inferior

mmedial

lateral and anterior

posterior

Answer 23

• Superior
  
  • Orbit
  • infraorbital n
  • infraorbital a and v
• Inferior
  
  • Roots of molars and premolars
• Medial
  
  • Nasal cavity
• Lateral and anterior
  
  • Cheek
• Posterior
  
  • infratemporal fossa
  • pterygopalatine fossa

Question 24

Maxilary sinus

drain

innervation

arterial

lympatics

Answer 24

• Drain
  
  • Middle meatus via semilunar hiatus
• Innervation
  
  • ASA, MSA, PSA V2
• Arterial supply
  
  • Eca
    
    • ASA MSA PSA
    • Infraorbital
• Submandibular nodes

Question 25

Paranasal sinus drainage

Answer 25

• Sphenoethmoidal recess
  
  • Sphenoid sinus
• Superior meatus
  
  • Posterior ethmoid cells
• Middle meatus
  
  • Anterior and middle ethmoid cells
  • Frontal sinus
  • Maxillary sinus
• Inferior meatus
  
  • Nasolacrimal duct