Connections of the Skull

Question 1

Common nasal meatus of Nasal Cavity

Answer 1

1. Cribriform plate and foramina ⇒ anterior cranial fossa
   * olfactory nerves, anterior ethmoidal artery and nerves
2. Piriform aperture ⇒ face
3. Incisive canal ⇒ oral cavity
   * nasopalatine artery + nasopalatine nerve of Scarpa
4. Sphenopalatine foramen ⇒ pterygopalatine fossa
   * superior posterior nasal nerves + sphenopalatine artery
5. Choana ⇒ nasopharynx
6. Aperture of sphenoid sinus ⇒ sphenoid sinus
   * ventillation

Question 2

Superior nasal meatus of Nasal cavity

Answer 2

⇒ posterior ethmoidal air cells

* ventillation

Question 3

Middle nasal meatus of Nasal cavity

Answer 3

⇒ anterior and middle ethmoidal air cells

• ventillation
  1. Ethmoidal infundibulum ⇒ frontal sinus
  2. aperture of maxillary sinus ⇒ maxillary sinus

Question 4

Inferior nasal meatus of Nasal cavity

Answer 4

1. Nasolacrimal canal ⇒ orbit

* nasolacrimal duct

Question 5

Oral cavity

Answer 5

1. Incisive canal ⇒ nasal cavity
   * nasopalatine artery + nasopalatine nerve of Scarpa
2. Greater palatine canal ⇒ pterygopalatine fossa
   * greater palatine nerve + descending palatine artery
3. Lesser palatine canal ⇒ pterygopalatine fossa
   * lesser palatine nerves
4. Mandibular canal ⇒ mental foramen
   * inferior alveolar artery, vein, nerve

Question 6

Tympanic cavity

Answer 6

1. Musculotubarian canal ⇒ external base of skull
   * tensor tympani muscle, auditory tube
2. Caroticotympanic canaliculi ⇒ carotid canal
   * caroticotympanic arteries + plexus
3. Chorda tympani canaliculi ⇒ facial canal
   * chorda tympani nerve
4. Stapedius canaliculi ⇒ facial canal
   * stapedius nerve
5. Tympanic canaliculus ⇒ fossula petrosa
   * tympanic nerve + inferior tympanic artery
6. Canal of lesser petrosal nerve ⇒ middle cranial fossa
   * lesser petrosal nerve + superior tympanic artery
7. Mastoid antrum ⇒ mastoid air cells
   * ventillation

Question 7

Orbit

Answer 7

1. Optic canal ⇒ middle cranial fossa
   * optic nerve + ophthalmic artery
2. Superior orbital fissure ⇒ middle cranial fossa
   * oculomotor, trochlear, ophthalmic, abducens nerve + superior ophthalmic vein
3. Inferior orbital fissure ⇒ pterygopalatine fossa
   ⇒ infratemporal fossa
   * infraorbital n, sygomatic n, inferior ophthalmic vein
   * infraorbital artery + vein
4. Nasolacrimal canal ⇒ inferior nasal meatus
   * nasolacrimal duct
5. Anterior ethmoid canal ⇒ anterior cranial fossa
   * anterior ethmoidal a,v,n
6. Posterior ethmoidal canal ⇒ posterior ethmoidal air cells, sphenoid sinus
   * posterior ethmoidal n,a,v
7. Infraorbital canal ⇒ face, fossa canine
   * infraorbital a,v,n
8. Frontal notch ⇒ supraorbital region
   * frontal nerve
9. Supraorbital foramen ⇒ supraorbital region
   * supraorbital nerve
10. Zygomatic canal ⇒ zygomaticofacial foramen/-temporal foramen
    * zygomaticotemporal/-facial branch

Question 8

Anterior cranial fossa

Answer 8

1. Cribriform plate ⇒ nasal cavity

* olfactory nerves, anterior ethmoidal a,v,n

Question 9

Middle cranial fossa

Answer 9

1. Optic canal ⇒ orbit
   * optic nerve, ophthalmic artery
2. Superior orbital fissure ⇒ orbit
   * oculomotor, trochlear, ophthalmic, abducens nerve, superior ophthalmic vein
3. Foramen rotundum ⇒ pterygopalatine fossa
   * maxillary nerve
4. Foramen ovale ⇒ external base of skull
   * mandibular nerve
5. Foramen lacerum ⇒ external base of skull
   * greater petrosal + lesser petrosal nerve
6. Foramen spinosum ⇒ external base of skull
   * middle meningeal artery
7. Carotid canal ⇒ external base of skull
   * internal carotid artery
8. Hiatus for canal of greater petrosal nerve ⇒ facial canal
9. Hiatus for canal of lesser petrosal nerve ⇒ tympanic cavity

Question 10

Posterior cranial fossa

Answer 10

1. Foramen magnum ⇒ vertebral canal
   * spinal cord, vertebral arteries, spinal arteries, accessory nerve
2. Internal acoustic meatus ⇒ fundus of internal acoustic meatus
   * facial n, vestibulocochlear n, labyrinthine a,v
3. Jugular foramen ⇒ external base of skull
   * glossopharyneal, vagus, accessory nerve, post. meninegal artery, internal jugular vein
4. Hypoglossal canal ⇒ external base of skull
   * hypoglossal nerve
5. Condylar canal ⇒ external base of skull
   * condylar emissary vein
6. Aqueducts of vestibule ⇒ inner ear, vestibule
   * peri- and endolymphatic communication

Question 11

External base of skull

Answer 11

1. Jugular foramen ⇒ posterior cranial fossa
   * glossopharyengal, vagus, accessory, IJV
2. Hypoglossal canal ⇒ post. cranial fossa
   * hypoglossal nerve
3. Condylar canal ⇒ post cranial fossa
   * condylar emissary vein
4. Foramen ovale ⇒ middle cranial fossa
   * mandibular n
5. Foramen spinosum ⇒ middle cranial fossa
   * middle meningeal a
6. Foramen lacerum ⇒ middle cranial fossa
   * greater + lesser petrosal nerves
7. Carotid canal ⇒ middle cranial fossa
   * internal carotid a
8. Stylomastoid foramen ⇒ end of facial canal
   * facial nerve
9. Pterygoid canal ⇒ pterygopalatine fossa
   * greater petrosal n, deep petrosal n
10. Cochlear canaliculus ⇒ inner ear
    * perilymphatic connection
11. Tympanic canaliculus ⇒ tympanic cavity
    * tympanic nerve
12. Musculotubarian canal ⇒ tymapnic cavity
    * tensor tympani muscle, auditory tube
13. Mastoid canaliculus ⇒ tympanomastoid fissure
    * auricular branch of vagus nerve

Question 12

Pterygopalatine fossa

Answer 12

1. Pterygoid canal ⇒ external base of skull
   * greater + deep petrosal nerve
2. Greater petrosal canal ⇒ oral cavity
   * greater petrosal n, descending palatine a
3. Lesser petrosal canal ⇒ oral cavity
   * lesser petrosal nerve
4. Inferior orbital fissure ⇒ orbit
   * infraorbital n, aygomatic n, inferior opthalmic vein
5. Pterygomaxillary fissure ⇒ infratemporal fossa
   * posterior superior alveolar nerves, maxillary a
6. Foramen rotundum ⇒ middle cranial fossa
   * maxillary nerve
7. Sphenopalatine foramen ⇒ nasal cavity
   * superior posterior nasal nerves, sphenopalatine a

Question 13

Infratemporal fossa

Answer 13

1. Pterygomaxillary fissure ⇒ pterygopalatine fossa
   * posterior superior alveolar nerves, maxillary a
2. Inferior orbital fissure ⇒ orbit
   * infraorbital a,v
3. Foramen ovale ⇒ middle cranial fossa
   * mandibular nerve
4. Foramen spinosum ⇒ middle cranial fossa
   * middle meningeal a
5. Petrotympanic fissure ⇒ tympanic cavity
   * chorda tympani
6. Alveolar foramina ⇒ upper teeth
   * posterior superior alveolar a,v

Question 14

Facial canal

Answer 14

1. Canal fro greater petrosal nerve ⇒ own hiatus
   * greater petrosal nerve
2. Stapedius canaliculus ⇒ tympanic cavity
   * stapedius nerve
3. Chorda tympani canaliculus ⇒ tympanic cavity
   * chorda tympani nerve