Internal Skull and Dural Sinuses Flashcards
What are the boundary points for separatig the interior skull into superior and inferior segments? What are the names of these structures, indicated by the image?
Frontal crest to right above the external occiptial protuberance
Name the structures indicated in the image as well as their boundaries.
- Between frontal and middle fossa:
- posterior border of the lesser wing of the sphenoid
- anterior clinoid processes
- anterior border of the prechiasmatic sulcus
- Between middle and posterior fossa
- superior ridge of the petrous part of the temporal bone
Which meningeal layer is the thinnest and adheres directly to the brain? Describe this layer’s level of vascularization.
Pia mater
highly vascularized by a network of fine blood vessels
What is the name of the second deepest meningial layer? What is the name of the space between this layer and the pia mater? What is this layer’s level of vascularization?
What is the name for the projections where CFS is reabsorbed into the dural venous sinuses?
Arachnoid mater
subarachnoid space (filled w/ CSF)
avascular
Arachnoid granulations
What causes the granular fovea on the cranial vault?
When the arachnoid granulations are very tall and create little divits on the cranium
What layer of the meninges is most superficial? What are its two layers?
Dura mater
- periosteal dura: lines the periosteum of the cranium
- meningeal dura: lines arachnoid mater
What is the name for the 2 layers of meningeal dura that divide cranial cavity into parts?
What is the name for the valve-less space between dura where CSF is reabsorbed inot venous system?
Dural infolding
Dural venous sinus
Identify the shown dural infoldings. Name their attachment points and their general shape.
- Falx cerebi (sickle shaped)
- Attacments
- crest galli
- frontal crest
- sagital sulcus
- internal occipital protuberance
- continuous with tentorium cerebelli (separates R & L) hemispheres of cerebrum
- Attacments
- Tentorium cerebelli (crescent shaped)
- Attachments
- anterior clinoid process
- superior ridge of petrous temporal bone
- posterior clinoid process
- transverse sulcus
- forms “tent” w/ falx cerebi
- separates cerebrum from cerebellum
- Attachments
- Falx cerebelli (sickle shaped0
- Attachments
- inferior to internal occipital protuberance
- internal occipital crest
- inferior to tentorium cerebelli/ partially separates hemispheres of cerebellum
- Attachments
- Diaphragma sellae (horizonal sheet)
- covering hypophyseal fossa– has an apeture for stalk of pituitary
- Attachment
- posterior clinoid process
- anterior clinoid process
Which dural infolding creates the structure through which the brain stem passs? What is the name of this structure?
tenrotium cerebelli, b/c it is unattached at the anterior border forms the tentorial notch, through which the brainstem passes
What is the arterial supply of the dura?
meningeal arteries
middle meningeal makes grooves in temporal bone
Identify the nerves innervating the dura mater indicated on the provided image
What are the two potential spaces contained in the dura?
extradural and subdural spaces
they exist as a restult of pathology or trauma
Name the structure indicated on the image.
Position?
Blood supply?
Drains to?
Superior sagittal sinus
- midline; superior border of falx cerebri
- receives blood
- frontal, parietal, occipital lobest
- drains into confluence of sinuses
Name the structure indicated on the image.
Position?
Blood supply?
Drains to?
Inferior sagittal sinus
- midline; inferior free border of falx cerebri
- receies blood
- veins along falx cerebri
- cerebral hemispheres of brain
- Drains into
- straing sinus
Name the structure indicated on the image.
Position?
Blood supply?
Drains to?
Striaght sinus
- midline; at intersection of falx cerebri & tentorium cerebelli
- Receives blood
- inferior saggial sinus & great cerebral vein
- Drains into
- confluence of sinuses & left transverse sinus