Head And Neck: Braincase Meninges Dural Sinus

Front 1

the skull is divided into two parts

Back 1

1. Neurocranium (braincase)

2. Visceroskeleton (faial skeleton)

Front 2

the skull is broken into the neurocranium and visceralcranium, the neurocranium is then further divided into...

Back 2

1. calvaria (superior, dome shape)

2. cranial base (inferior)

Front 3

what is the dipole

Back 3

its the arrangement of bone in the skull

Two layers of compact bone that sandwich spongy (calceneous) bone

Front 4

what are the veins in the scalp bone called? where do they drain

Back 4

dipole veins drain externally to scalp veins

**can also drain to internal cranial cavity

Front 5

besides dipole veins which drain externally to scalp veins what are the other type of vein in the skull? where to they drain

Back 5

emissiary veins

originate from dural sinus (within cranial cavity), drain extracranially to scalp veins, dont vecessarily link to dipolic

**pass through small calvaria foramen (hole in the top part of the skull)

Front 6

what are the 4 paired bones and 2 unpaired bones of the neurocranium

Back 6

Unpaired: frontal, occipital, ethmoid, sphenoid

Paired: temporal, parietal

Front 7

what are the three main suture lines in the neurocranium

Back 7

1. coronal: frontal to parietal, meet at bregma

2. saggital: top of head, parietal, lambda at back where it meets occipital

3. lambdoidal: back of head, occipital to parietal, lambda-meets occipital and 2 parietal

Front 8

where is the
bregma
lambda
pterion

Back 8

bregma: where coronal and saggital suture lines meet, top of head, to the front

lambda: paired, where the parietal bones and occipital bone meet, kinda near the inion

Pterion: lateral, near temple, temporal, parital, frontal, and sphenoid come together

Front 9

what is contained within the anterior fossa

Back 9

frontal lobe of brain
olfactory bulb
olfactory tract

Front 10

what is the opening in the anterior fossa, what passes through

Back 10

cribiform plate, olfactory N (CN I)

*part of ethmoid bone

Front 11

what is the crista galli?
what attached here?

Back 11

midline feature of anterior fossa

**ridge of bone that projects from the cribiform plate (part of ethmoid bone)

*flax cerebri attaches here

Front 12

where do the olfactory bulbs lie?

Back 12

on either side of the crista galli, on the cribiform plate

Front 13

what is in the middle cranial fossa

Back 13

temporal lobe of brain

Front 14

there are 7 holes to know in the middle cranial fossa, what are they, what pass through them

"Oh shit, regular ovulation stifles lovers cum"

Back 14

1. Optic canal: optic N, opthalmic A
2. Superior Orbital Fissure: CN III, IV, V1 (opthalmic N), VI, superior opthalmic V
3. Foramen Rotundum: V2 Maxillary N
4. Foramen Ovale: V3 mandibular N, lesser petrosal
5. Foramen Spinosum: middle meningeal a/v
6. Foramen Lacerum: nothing is IN it, internal carotid a passes BY it
7. Carotif canal: internal carotid A

Front 15

what are 4 bony features of the middle cranial fossa?

Back 15

Anterior clinoid fossa:
Sella Turcica:
Posterior Clinoid:
Petrous Ridge:

Front 16

what passes through the Optic canal

Back 16

CN II
opthalmic A

Front 17

what passes through the superior orbital fossa?

Back 17

CN III
CN IV
CN V1 Opthalmic branch
CN VI
Superior Opthalmic V

Front 18

what passes through foramen rotundum?

Back 18

CN V2 Maxillary N

Front 19

What passes through the foramen ovale?

Back 19

CN V3: mandibular N
Lesser Petrosal N

Front 20

what passes through the Foramen Spinosum

Back 20

middle meningeal A/V

Front 21

what passes through the foramen lacerum

Back 21

NOTHING,
internal caroted passes by

Front 22

what passes through the carotid canal

Back 22

internal carotid a

Front 23

Name the 4 holes in the posterior cranial fossa? what passes through them?

"is jess helping fish"

Back 23

1. Internal Acoustic Meatus: CN VII, CN VIII
2. Jugular Foramen: origin of internal jugular v, CN 9, 10, 11
3. Hypoglossal Canal: CN XII
4. Foramen Magnum: spinal root of AN XI, vertebral A, medulla

Front 24

what passes through the internal acoustic meatus

Back 24

CN VII
CN VIII

Front 25

what passes through the jugular foramen?

Back 25

orgin of internal jugular v
CN 9
CN 10
CN 11

Front 26

what passes through the hypoglossal canal

Back 26

hypoglossal N, CN XII

Front 27

What passes through the foramen magnum?

Back 27

Vertebral A
medulla
spinal root of CN XI

Front 28

what structures are located in the posterior cranial fossa

Back 28

brainstem: midbrain, pons, medulla
Celebellum

Front 29

from an inferior view, what 7 holes can we see from the skull?

"ovulation stifles lovers cum, have some fun"

Back 29

Foramen ovale: V3, lesser petrosal
foramen spinosum: middle memingeal
foramen lacerum: nothing, internal carotid a passes by
carotid canal: internal caortid A
hypoglossal canal: CN XII
stylomastoid foramen: facial N
foramen magnum: vertebral a, medulla, spinal root of CN XI

Front 30

what are the 3 layers of meninges

Back 30

1. Pia: thin, right on brain, delicate
2. Arachnoid: lies on pia, thin strands called pia trabeculae
3. Dura: directly on braincase, no epidural space (made of endosteal layer and meningeal layer)

**CT that line innersurface of cranial cavity, form a complete sac around the brain/spinal cord

Front 31

what are leptomeninges

Back 31

combo of pia and arachnoid

Front 32

what space contains CSF

Back 32

suparachnoid space

**deep to arachnoid, sometimes called leptomeningeal space

Front 33

what are the two layers of cranial Dura

Back 33

1. endosteal: fused to inner surface of calvaria, fx as periosteum
2. Meningeal: deep (internal to endosteal), sometimes just called dura, made of meningeal layer and dural border layer


**easier way to think: dura is made of dural border, meningeal, enodsteal

Front 34

So... Dura is made of 1. meningeal and 2. enodsteal, the meningeal is then divided into 2 additional layers, 1. meningeal 2, Dural border

tell me about the attachment of the dural border layer

Back 34

cells of the dural border are only weakly joined to one another

**if a blood vessel ruptures here blood can accumulate, within dural border, dural border hematoma

Front 35

what are the 3 types of intrcranial hemmorage

Back 35

1. epidural: middle meningeal, blood btwn bone and dura
2. Subarachnoid Hemmorage: aneurysm, blood accumulates in subarachnoid space
3. Dural Border: bridging vein, blood is within dural border layer, intradural

Front 36

if the blood is accumulating... what type of hematoma

1. in the dura
2. Between bone and dura
3. subarachnoid space

Back 36

1. dural border hematoma
2. epidural
3. subarachnoid hemmorage, aneurysm

Front 37

a tear in the middle meningeal creates what type of hematoma, where does blood accumulate, where does middle meningeal leave the head

Back 37

foramen spinosum
epidural hemoatoma
blood btwn bone and dura (creates an epidural space)

**cresent shaped

Front 38

what type of hematoma do you get with an aneurysm? whats the name of the space, what is another name for the space

Back 38

surarachnoid hemmorage
blood accumulates in subarachnoid space (btwn pia and arachnoid)

subarachnoid space aka leptomeningeal space

Front 39

what happens when a bridging vein tears?

Back 39

blood accumulates in dural border layer, (intradural hematoma, not subdural)

Front 40

what layer of the meninges has its own innervation and blood supply

Back 40

Dura

Middle meningeal A (from maxillary)
Trigeminal N: supplies dura and arachnoid of middle cranial fossa

Front 41

what branches supply the posterior fossa

Back 41

C2-C3
enter cranial cavity with CN X and CN VII

*the trigeminal supplies the middle cranial fossa

Front 42

what are dural reflections?
name two

Back 42

fusion of 2 adjacent layers of dura

1. flax cerebri: attaches to crista galli, located btwn the 2 sides of brain

2, Tentorium Cerebelli: roof of post fossa, tent over the celebellum

Front 43

what is the tentorial notch? waht does it allow?

Back 43

opening formed by tentorium cerebelli around the brainstem

allows brainstem to go inferior from middle cranial fossa to post cranial fossa

Front 44

what does the diaphragm sella do? what does it cover

Back 44

roof over sella turcica,
covers pituitary gland

Front 45

name 4 unpaired sinuses

Back 45

superior sagital
inferior sagital
straight
great cerebral (vein of Galen)

Front 46

name 6 paired sinus

Back 46

1. cavernous
2. inferior petrosal
3. superior petrosal
4. tansverse
5. confluence of sinuses
6. sigmoid sinus

Front 47

How does blood move through the sinus? start with what empties into the confluence and trace it to the IJV

Back 47

inferior sagittal --> straight --> confluence

superior sagittal --> confluence

confluence --> transverse --> sigmoid --> internal jugular

Front 48

where does the confluence get its blood

Back 48

1. Superior Sagittal
2. Inferiot sagittal to straight to confluence

Front 49

dural sinuses are endothelial lined channels btwn what two layers of dura

Back 49

endosteal and mengial layers of dura

Front 50

so you can trace blood from confluence into IJV, what are some other paths that dont use the confluence to enter IJV

Back 50

Cavernous --> superior petrosal --> sigmoid --> IJV

Cavernous --> inferior petrosal --> IJV

Front 51

what is the most direct way for blood to enter the IJV from the skull

Back 51

Cavernous --> inferior petrosal --> IJV