adhered to the undersurface of cranium (part of dura mater)
continuous with dural layer which covers spinal cord (part of dura mater)
Part of dura mater that separates the right and left cerebral hemispheres
From dura mater and separates the cerebellum from the cerebral hemispheres and allows communication between these 2 compartments through the tentorial incisure
allows communication between the cerebellum and cerebral hemispheres through the tentorium cerebeli
lies inferior to the cerebellar tentorium and partially separates the cerebrellar hemispheres
Dural venous sinuses
In between teh 2 layers of the dura mater and collect venous drainage and CSF of the brain and drain into the internal jugular veins of the neck
Suspended between the clinoid processes forming a partial roof over the hypophyseal fossa and pituitary gland; has an opening for the infundibulum of the pit gland
Blood supply to the dura mater
Middle meningeal artery (from maxillary artery)
Communication of superior sagittal sinus with...
venous lacunae (numerous arachnoid villa and granulations project into lacunae)
Occipital sinus communicates with
vertebral veins through the foramen magnum and with transverse sinuses
Where does cavernous sinus drain?
into transverse sinus through superior petrosal sinus
What travels through the cavernous sinus?
internal carotid artery and CN6
What is on the lateral wall of the cavernous sinus?
CN3, CN4, and CN5-ophthalmic and maxillary divisions
What structures are associated with cavernous sinus?
Hypophysis cerebri-lies medial in sella turcica; veins of the face - connected with cavernous sinus via facial vein and inferior ophthalmic vein (IMPT route for spread of infection from the face)
Where does infection from the mastoid antrum spread?
Sigmoid sinus and cause thrombosis and septicemia
Danger triangle of the face
blood from medial angle of eye, nose, and lips drains inferiorly via facial vein (especially if erect), the facial vein has NO valves and blood can move in the opposite direction - venous blood from the face enters the cavernous sinus. THrombophlebitis of facial veins can lead to thrombophlebitis of cavernous sinus and spread via the dural sinuses
Composition of arachnoid and pia mater
loose connective tissue
Through what does subarachnoid space communicate with the 4th ventricle?
Foramen of Magendie and Paired foramen of Luschka
Where is CSF located?
web-like area that attaches arachnoid to pia
numerous fringes formed by vascular membrane and make up the choroid plexus
produces the CSF in the lateral, 3rd, and 4th ventricle
space between pia mater and the vessels formed by invagination of the pia in areas where vessles enter/exit the brain
Strong blow to the side of the head
laceration of the middle meningeal artery and epidural hematoma
How can epidural hematoma be found on PE?
Pupil dilates instead of constricting because the oculomotor nerve is pinched with brain swelling
Strong blow to the front or back of the head or sudden stop from acceleration leads to...
shearing force on the vessels of the brain as a result of the brain swaying back and forth in the head - most likely effects the emissary veins leading to subdural hematoma
Who is affected most by a sudden stop from acceleration?
elderly and or/with atrophy or tension
Jarring motions can lead to
contusions - coup and contracoup of fronto-temporal/occipital
Coup and contracoup
initial acceleration forward to back - brain keep moving forward and head moves back
Diffuse axonal injury
injury widespread over brain - intracranial hematoma grows in size and exerts pressure on the underlying brain that is potentially fatal