Test 2 Part 1 Flashcards
viscerocranium
Facial Skeleton
Neurocranium
Cranial cavity and skull cap (calvaria)
Bones of viscerocranium
2 Nasal bone
Horizontal plate of palatine bone
2 lacrimal bones
Perpendicular plate of ethmoid bone
2 Zymgomatic bones
Maxilla
Inf. Nasal conchae
Vomer
Mandible
Bones of Cranial Cavity
Frontal bone
2 parietal bones
2 temporal bones
occipital bone
Superior Nuchal Line
Where upper trap attaches to occipital bone
Diseases that may lead to formation of Wormian bones
Osteogenesis imperfecta (brittle bone disease)
Rickets
Vitamin D deficiency
cleidocranial dysostosis (missing or small clavicle)
Down syndrome
How many layers of bone in Neurocranium?
3
3 Layers of Neurocranium bone
Superficial - outer table (compact, dense)
Intermediate - Cancellous bone (diploe)
Houses and protects red bone marrow
Houses venous pathways
Deep - Inner table (compact, dense, brittle)
Diploid Veins Functions
drain the scalp
drain the neurocranium
terminate in dural venous sinuses q
Dural venous sinuses
venous channels formed from dura mater found in the cranial cavity
Emissary veins
receive venous drainage from the scalp and diploic veins, pierce the skill and drain internally.
Don’t have valves, so provide route for the spread of infection from the scalp to the cranial cavity and can affect the brain and or the meninges.
Parts of the Orbit
Roof
Medial wall
lateral wall
floor
apex
Roof of orbit
Frontal bone with orbital plate
Medial wall of orbit
lacrimal bone
ethmoid bone (orbital plate)
small tip of perpendicular plate of the palatine bone
Lateral wall of orbit
zygomatic bone
floor of orbit
maxilla
Apex of orbit
sphenoid bone (greater wing)
contains the optic canal, Optic nerve CN II, and
ophthalmic artery
Openings of the orbit
Optic canal
sup. orbital fissure
Inf. orbital fissure
infraorbital nerve
Nasolacrimal canal (contains nasolacrimal duct)
Optic Canal contents
Optic nerve (CN II)
ophthalmic artery
Sup. orbital fissure contents
???
Inf. orbital fissure
infraorbital vein
infraorbital nerve
infra-orbital groove contents
infraorbital nerve
Pterion
Where parietal, temporal, and sphenoid bone meet.
This is a weak point. Important because damage to pterion will damage the ant. branch of middle meningeal artery and an epidural hematoma forms.
Fatality rates of epidural hematomas?
15-20% Used to be 50% though
