INTERNAL SURFACE OF CRANIAL BASE

is divided into: the anterior cranial fossa

the middle cranial fossa

the posterior cranial fossa

anterior cranial fossa:

1. frontal bone - orbital parts - superior surfaces

2. ethmoidal bone - cribriform plate olfactory n.(1st)

3. sphenoid bone - lesser wings

middle cranial fossa:

1. sphenoid bone body - hypophysial fossa (hypophysis=pituitary gland)

- optic canal - optic nerve (2nd)

- ophthalmic a.

- sulcus chiasmatis (optic chiasm)

greater wings - cerebral surface

foramen rotundum: Maxillary n. (5th/2)

foramen ovale: Mandibular n. (5th/3)

foramen spinosum: middle meningeal a. superior orbital fissure: Oculomotor n.(3rd)

Trochlear n.(4th)

Abducent n. (6th)

Ophthalmic n.(5th/l)

Sup. ophthalmic v.

2. temporal bone - petrous part - anterior surface

trigeminal impression

tegmen tympani

carotid canal internal carotid a. foramen lacerum - borders:sphenoid,petrous,occipital

posterior cranial fossa: 1. temporal bone -petrous part -internal acoustic meatus:

Facial n. (7th)

Vestibulocochlear n. (8th)

- mastoid part - internal surface

2. occipital bone - basilar part - superior surface

- lateral parts - superior surface

- squama - internal surface

jugular foramen - borders: dorsal margin of petrous part

occipital b. - jugular notch

internal jugular v. Glossopharyngeal n. (9th)

Vagus n. (10th)

Accessory n. (11th)

hypoglossal canal: Hypoglossal n. (12th)

NORMA BASALIS (External surface of cranial base)

maxilla - body - infratemporal surf.

- alveolar process

- palatine process

- zygomatic process

zygomtic bone

zygomatic arch

palatine bone - horizontal plate - inferior surface

sphenoid bone - body - inferior surface

- greater wings - infratemporal sufrace

- pterygoid process

vomer

temporal bone - petrous part - inferior surface

- squamous part - ext. surf.- zygomatic process, condylar

- tympanic part fossa

- styloid part

- mastoid part - external surface

occipital bone - basilar part - inferior surface

- lateral parts - inferior surface

- squamous part - external surf. - from foramen magnum

to superior nuchal line

!!! other important structurs:

inferior orbital fissure: borders:greater wings

maxilla

posterior nasal apertures:

borders:horizontal plate of palatine

madial plate of pterygoid process

inf. surf. of sphenoid body

vomer

infratemporal fossa:

borders: ifratemporal surface of greater wings

body of maxilla -infratemporal surface

lateral plate of pterygoid process

ramus of mandible (lateral wall)

VESSELS AND NERVES TRANSMITTED THROUGH THE FORAMINA ON THE

NORMA BASALIS:

greater palatine foramen: greater palatine n.

lesser palatine foramina: lesser palatine nerves

pterygoid canal: nerve and vessels of pterygoid canal

foramen ovale: mandibular n.

foramen spinosum: middle meningeal a.

carotid canal: internal carotid a.

jugular foramen: internal jugular v.

9th, 10th, 11th cerebral nerves

stylomastoid foramen: facial n.

mastoid and condylar canals: emissary veins

hypoglossal canal hypoglossal n.

ORBIT

orbital opening:

borders: frontal bone

zygomatic bone

maxilla

superior wall: frontal bone - orbital part - orbital surface

sphenoid bone - lesser wing

medial wall: maxilla - frontal process

lacrimal bone ethmoid bone - labyrints - lateral (orbital) plate

inferior wall: zygomatic bone

maxilla - body - orbital surface

lateral wall: zygomatic bone sphenoid bone - greater wing - orbital surface

!!!important structures:

optic canal (optic nerve, central a. of retina) superior orbital fissure -

borders: greater wings, lesser wings

(transmits:III.,IV.,VI.,V/l nerves, ophthalmic a., v.)

inferior orbital fissure -

borders: greater wings

maxilla

transmits:infraorbital a. v., n.,

inf. ophthalmic v.

BONY NASAL CAVITY

anterior nasal aperture

borders: maxilla and nasal bones

posterior nasal apertures - choanae

borders: superiorly: sphenoid bone - body

laterally: pterygoid process - medial plate

inferiorly: palatine bone horizontal plate

roof: nasal bones

frontal bone

cribriform plate of ethmoid bone

body of sphenoid bone

floor: maxilla - palatine process

palatine bone - horizontal plate

lateral wall: nasal bone

lacrimal bone

maxilla - frontal process

- body - nasal surface

ethmoid bone - medial plate

palatine bone - perpendicular plate

pterygoid process of sphenoid bone medial plate)

nasal septum: ethmoid bone - perpendicular plate (anterosup.part)

vomer (posteroinf. part)

nasal conchae superior and middle are projections of ethmoid b.

- inferior concha (separate bone connected to the maxillary nasal surface)

nasal meatuses - superior, middle, inferior

PARANASAL SINUSES - cavities in bones bordering nasal cavity

l. frontal sinus

2. maxillary sinus

3. ethmoid sinuses - anterior, middle and posterior

4. sphenoid sinus

openings of paranasal sinuses:

sphenoid and post. ethmoid sinuses open into the superior nasal meatus

frontal, ant. and middle ethmoid, maxillary sinuses open into the middle nasal meatus

(nasolacrimal canal - into inferior nasal meatus)