Dural Venous Sinuses Flashcards
Dura mater
Two layers, periosteal and then meningeal deep layer
These layers are fused except in specific areas where they separate to form large blood filled dural venous sinuses
Arachnoid
Delicate web of collagen and elastic fibers forming arachnoid trabeculae
Cranial dural septa
Meningeal layer of dura mater extends as flat partitions deep into the cranial cavity at four locations Falx cerebri Tentorium cerebelli Falx cerebelli Diaphragma sellae Dural venous sinuses form within these septa: Superior/inferior sagittal sinuses Straight sinus Sigmoid sinus Transverse sinus
Blood supply to meninges
External carotid gives off maxillary which gives off middle meningeal artery
Middle meningeal artery transverses foramen spinosum and splits into anterior/frontal and parietal/posterior branches
Superior sagittal sinus
Lies along superior margin of falx cerebri
Begins at crista galli and ends at occipital protuberance
Inferior sagittal sinus
Lies along inferior margin of falx cerebri
Ends in straight sinus
Straight sinus
Lies at intersection of falx cerebri and tentorium cerebelli
Formed at intersection of inferior sagittal sinus with great cerebral vein
Joins confluence of sinuses
Confluence of sinuses
Common confluence of superior sagittal, transverse and straight sinuses
Transverse sinus
Begins at confluence of sinuses
Extends along edges of tentorium cerebelli
Right receives blood from superior sagittal sinus
Left (dominant) receives blood from straight sinus
Sigmoid sinus
Continuations on either side of the straight sinus
S shaped
End at jugular foramina
Become internal jugular veins
Cavernous sinus
Large venous plexus on each side of sella turcica
Superior petrosal sinus
Run on either side from cavernous sinus to junction of transverse and sigmoid sinuses
Inferior petrosal sinus
Run on either side from cavernous sinus to junction of sigmoid sinus and internal jugular vein
CSF flow chart
Choroid plexus Ventricles Through apertures Into subarachnoid space Through arachnoid villi Into dural venous sinuses Into internal jugular veins
Cavernous sinus receives drainage from which veins
Superior and inferior ophthalmic veins
Superficial middle cerebral vein
Sphenoparietal sinus
Arteries and nerves associated with the cavernous sinuses
Small branches of internal carotid artery Carotid plexus of sympathetic nerves Abducent nerve Oculomotor nerve Trochlear nerve 2 divisions of the trigeminal nerve
Basilar plexus
Connects the inferior petrosal sinuses and communicates inferiorly with the internal venous plexus
Emissary veins
Connect the dural sinuses with veins outside the cranium
Middle meningeal veins drain into what
Pterygoid venous plexus
Circle of willis
Intracranial parts of vertebral arteries unite to form basilar artery
Basilar artery forms posterior cerebral arteries which are connected to the middle cerebral arteries by the posterior communicating arteries
Internal carotid arteries form the middle and anterior cerebral arteries
Anterior cerebral arteries are connected by anterior communicating artery
Epidermal hematoma caused by
Middle meningeal artery, shaped like a “lens” on imaging
Subdural hematoma caused by
Bridging veins, shaped like a crescent on imaging
Subarachnoid hemorrhage caused by
Cerebral arteries, has spiderweb appearance on imaging
CSF description
Formed by the choroid plexus in each ventricle. Produced by secretion of a fluid from the ependymal cells that originate from the blood plasma
Has greater sodium, hydrogen, calcium and less potassium than plasma
Probably need to look at this stuff more in the book .. shitty lecture material
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