Osteology of the Skull - Dural Venous Sinuses & Cranial Base

space within the folds containing blood

Venus sinus

- "tough mother"

- two inseparable layers: periosteal & meningeal

- white inner layer

Dura mater

interior surface of the bone, against the bone

periosteal layer

against the arachnoid mater, most interior, deeper of the two layers

meningeal layer

- "spider mother"

- shiny, translucent

- fibrous, gelatinous-like

- boundary of a real space

Arachnoid mater

- "gentle mother"

- microscopic lining along the surface of the brain, dipping in and out of brain areas

Pia mater

inflammation of the meninges due to viral, bacterial, fungal infections or damage

Meningitis

potential spaces

Epidural and subdural (deep to dura mater) are

- space that can be created where there is normally no space

- can be due to a bleed (hemorrhage, hematoma)

- not supposed to be present

Potential spaces

- real space with vessels and CSF

- deep to the arachnoid mater

Subarachnoid

- protect the brain

- support vessels and venous sinuses

- enclose the subarachnoid space

Function of meningeal layers

scalp > bone > dura mater > subdural (potential space) > arachnoid mater > subarachnoid (real space) > pia mater

Order of layers

- where arachnoid mater dips into the venous sinus

- how the CSF gets out of the subarachnoid space and into the blood system

arachnoid granulations

- connection of dural venous sinuses with veins outside the cranium

- not within the dura but pass through the cranium

- service the scalp

- scalp infections in the "L" layer can spread into the cranial cavity and meninges via these

Emissary veins

spread into, emissary veins

scalp infections in the "L" layer can ______ _____ the cranial cavity and meninges via _______ ______

Diploic vv

This is the

Emissary vv

This is the

connect dural sinuses to scalp veins

The emissary foramina

4 ventricles of the brain itself

CSF is produced in the

brown tissue around the third ventricle continuously producing cerebrospinal fluid

choroid plexus

arachnoid granulations

CSF gets out via

subarachnoid space

The real space that the CSF is in is the

L2 at the end of the spinal cord proper

Subarachnoid space terminates around

- mechanical protection

- pathway for removal of brain metabolites

Function of CSF

- propagations of the arachnoid that protrude through the meningeal layer into the dural venous sinuses

- site of transfer of CSF to venous system

- may cause pits on the internal surface of cranium

CSF to venous sinuses

between hemisphere of cerebrum (sickle shaped)

falx cerebri

in between the hemispheres of the cerebellum

falx cerebelli

between cerebrum and cerebellum is a horizontal fold, creating a sort of tent

tentorium cerebelli

folds around the sides of the sella turcica

diaphragma sella

in falx cerebri:

superior sagittal sinus

in inferior part of the falx cerebri:

inferior sagittal sinus

left, right

There is a ______ and a _______ transverse sinus

superior sagittal sinus

Radiograph sinuses: 21

straight sinus

Radiograph sinuses: a

great cerebral vein (Galen)

Radiograph sinuses: b

inferior petrosal sinus

Radiograph sinuses: c

sigmoid sinus

Radiograph sinuses: d

transverse sinus

Radiograph sinuses: e

confluence of sinuses

Radiograph sinuses: f

internal jugular vein

Radiograph sinuses: g

- grooves for sinuses

- grooves for the meningeal aa

- foramen for emissary veins

- granular foveolae for arachnoid granulations

Connection to osteology

arachnoid granulation

This is the

subarachnoid space

This is the

meningeal dural mater

This is the

right lateral ventricle

This is the

median aperture

This is the

central canal

This is the

fourth ventricle

This is the

lateral aperture

This is the

cerebral aqueduct

This is the

third ventricle

This is the

interventricular foramen

This is the

choroid plexus

This is the

superior sagittal sinus

This is the

CSF in subarachnoid space

This is the

Dural venous sinus

This is the

arachnoid granulations

This is the

Falx cerebelli

This is the

Tenorium cerebelli

This is the

Falx cerebri

This is the

Diaphragma sella

This is the

cavernous sinus

This is the

Inferior petrosal sinus

This is the

Superior petrosal sinus

This is the

Superior sagittal sinus

This is the

Inferior sagittal sinus

This is the

Great cerebral vein

This is the

Straight sinus

This is the

Confluence of sinuses

This is the

Transverse sinus

This is the

Sigmoid sinus

This is the

Occipital sinus

This is the

Jugular foramen to IJV

This is the

Lt. sphenoparietal sinus

This is the

Lt. cavernous sinus

This is the

Lt. superior petrosal sinus, draining to sigmoid sinus

This is the

Lt. inferior petrosal sinus, draining to the IJV

This is the

great vein of Galen

This is the

inferior sagittal sinus

This is the

Straight sinus (great vein and inferior sagittal converge)

This is the

confluence of sinuses

This is the

Rt. transverse sinus

This is the

Rt. sigmoid sinus

This is the

jugular foramen and IJV

This is the

middle meningeal artery

This is the

Rt. superior opthalamic v

This is the

superior sagittal sinus

This is the