Lecture 7 part I Flashcards
What is the Dura Mater
A tough, fibrous sack that surround the brain and has firm attachment points to the skull and sacrum. creates the dural folds and venous sinus system of the brain.
What is the arachnoid mater
named for fine, web-like appearance. middle layer, CSF flows underneath this layer
What are arachnoid villi
Membranous filters that allow CSF to pass into venous blood of the superior sagittal sinus. Structures responsible for resorbing CSF and returning it to to blood
What is the pia mater
Very thin layer, adherent to the brain and spinal cord. impermeable to fluid, covers every area except for some ventricular system area.
Where is the falx cerebri
located in the longitudinal fissure, separates hemispheres of cerebrum
Where is the tentorium cerebelli
between the cerebellum and occipital lobe
What is the function of the falx cerebelli
separates cerebellar hemispheres in the posterior cranial fossa
What is the seller diaphragm
covers the pituitary in its fossa.
What are denticulate ligaments
part of pia mater attach to dura mater
What is the function of the filum terminale
anchors conus medullaris to sacrum/coccyx
What are 4 CSF properties
small volume 150ml
low pressure 10mmhg
choroid plexus produce 400-500ml/day
CSF propelled cranially by brain movements and artery pulsations
What is the function of the arachnoid trabeculae
Keeps the brain in place
CSF flows from lateral ventricles into third ventricle via ?
interventricular foramen (of monro)
What are the lateral ventricles and their function
c-shaped spaces derived from the neural tube. Spaces curve from medial part of hemispheres around into the temporal lobes, allow movement of CSF
Where is the third ventricle
between halves of thalamus and hypothalamus
Where is the Cerebral aqueduct (of sylvius) and what does it connect
it is in the midbrain and connects the third and fourth ventricles.
Where is the fourth ventricle
between the medulla and cerebellum
Where ought one do a spinal tap
Into the cauda equina below L3
What happens to CSF in the 4th ventricle
CSF passes down into the spinal canal or exits into subarachnoid space
CSF ascends to superior sagittal sinus to be reabsorbed by?
arachnoid granulations
CSF enters the subarachnoid space by exiting the 4th ventricle through?
foramina of Luschka and Magendie
What are the 2 channels from the ventricular system that pass through the neural tissue?
Foramina of Magendie (midline) and Luschka (lateral)
What is the function of the choroid plexus
Generates CSF in lateral 3rd, 4th ventricles by filtering blood from capillaries that run through it
CSF ascends in the __then drains into venous dural sinuses via arachnoid villi?
subarachnoid space
What lines the ventricles
ependymal cells (epithelial-like neuroglial cells)
What is the import of the permeability of the brain CSF barrier
It allows metabolites of neurotransmitters to diffuse from the brain to ventricles and thus to be detected in spinal taps
What are arachnoid granulations
protrusions into dura created by arachnoid villi
What do cerebral veins drain into
dural sinuses
What does the common carotid artery branch from
brachiocephalic artery or aortic arch
What is the carotid sinus
Where the internal carotid splits from external carotid
What are the branches of the internal carotid
anterior and middle cerebral arteries
What artery supplies most of the cerebral hemispheres
internal carotid artery
Where does the vertebral artery travel
this artery passes through transverse foramina of C1-6 (not 7)
Supplies spinal cord, brain stem, inner ear, cerebellum, occipital and temporal lobes?
Basilar-Vertebral system
this artery penetrates the atlanto-occipital membrane and dura ?
vetrebral artery
these arteries unite to form the basilar artery on ventral medulla
vertebral arteries
What branches from the vertebral arteries
spinal arteries and posterior inferior cerebellar arteries
Where is the basilar artery
this artery ascends on ventral surface of brainstem
What branches of the basilar artery
anterior inferior cerebellar, pontine, superior cerebellar and posterior cerebral arteries brach off here?
