week 5 - neuro (meninges, external brain, ventricles) Flashcards
What are the three meningeal layers?
Dura, Arachnoid and Pia
What are the two layers of the dura in the cranium?
Periosteal/outer endosteal and inner meningeal layer
What is contained within the outer endosteal dural layer?
blood vessels and fibrous processes
Name all 13 dural venous sinuses
superior sagittal sinus, inferior sagittal sinus, straight sinus, occipital sinus, transverse sinus, sigmoid sinus, marginal sinus, superior petrosal sinus, inferior petrosal sinus, petrosquamous sinus, cavernous sinus, sphenoparietal sinus, intercavernous sinus.
What part of the dura do the dural folds come from?
The inner meningeal layer - the outer layer is attached to the inner surface of the skull
What is the falx cerebri?
A dural fold that separates the left and right cerebral hemispheres - located in the longitudinal cerebral fissure
What is the falx cerebelli?
A dural fold that separates the two cerebellar hemispheres
What is the tentorium cerebelli?
A dural fold that separates the cerebrum from the cerebellum
What is the diaphragma sellae?
A dural fold that forms a roof over the hypophysial fossa of the sphenoid - covering the pituitary gland
What is the function of the dura?
To support and protect the CNS, separates parts of the brain with dural folds
What is the tentorial notch?
The anterior opening between the tentorium cerebelli and opening for the passage of the brainstem
What is the infundibulum stalk?
Also known as pituitary stalk, the tube-like piece of brain between the pituitary and brain. largely sits outside the blood-brain barrier
What is Meckel’s cave?
Also known as trigeminal cave, it is a cerebrospinal fluid containing pouch in the middle cranial fossa that houses the trigeminal ganglion
Where is the superior sagittal sinus?
In the superior aspect of the falx cerebri, mid sagittal plane
Where does the superior sagittal sinus drain into?
Confluence of sinuses
What area does the superior sagittal sinus drain?
Cerebral hemispheres, falx cerebri, skull, pericranium
What are the tributaries of the inferior sagittal sinus?
Superior cerebral veins, veins of the falx cerebri, meningeal veins, diploic veins of the skull, emissary veins from the pericranium
Where is the inferior sagittal sinus?
On the inferior border of the falx cerebri, arcing in the sagittal midline
What does the inferior sagittal sinus drain into?
Straight sinus
What are the tributaries of the inferior sagittal sinus?
Veins of falx cerebri, anterior pericallosal vein
What is the drainage area of the inferior sagittal sinus?
Falx cerebri, medial surfaces of cerebral hemispheres
Where is the straight sinus?
In the sagittal plane, at the junction of the tentorium cerebelli and falx cerebri
What are the tributaries of the straight sinus?
The inferior sagittal sinus and the great cerebral vein mainly
Where is the transverse sinus?
It runs along the superior outside edge of the tentorium cerebelli. at the level of the external occipital protuberance
What does the transverse venous sinus drain into?
The sigmoid sinus
What are the tributaries of the transverse venous sinuses?
Inferior cerebral veins, inferior cerebellar veins, diploic veins
Where is the sigmoid sinus? (where does it come from and run into?
Runs inferiorly from the transverse sinus into the internal jugular vein
What area does the Sigmoid sinus drain?
Transverse sinus, cerebellum, pons, medulla oblongata
What are the tributaries of the sigmoid sinus?
Mastoid emissary veins, condylar emissary veins, inferior cerebellar veins
Where are the cavernous sinuses?
They are paired venous cavities that sit on either side of the sphenoid bone, extending from the most posterior aspect of the orbit to the petrous part of the temporal bone
What are the tributaries of the cavernous sinuses?
Superior ophthalmic vein, Inferior ophthalmic vein, superficial middle cerebral vein, middle meningeal vein, hypophyseal vein
Where do the cavernous sinuses drain into?
Superior and inferior petrosal sinuses
What are the contents of the cavernous sinus?
OTOMCAT Oculomotor nerve, Trochlear nerve, Ophthalmic nerve, Maxillary nerve, internal carotid artery, abducens nerve
Where is the superior petrosal sinus?
A small narrow dural venous sinus in the anterolateral margin of the tentorium cerebelli, from the cavernous sinus to the transverse sinus