Meningies Flashcards
What do meningies do?
provide protection for the brain. (CNS)
contain, circulate, and recycle CSF. (cerebral spinal fluid)
innervated and vascularized.
contain dural sinuses and partitions.
How many layers does the menengies have?
3
Name the 3 layers of the meningies.
Dura mater (periosteal & Meningeal), arachnoid membrane, and Pia mater
Dura Mater
outermost layer, thick collagenous layer, sits against inside of skull.
arachnoid membrane
looks like and sticks like clear wrap. Thin. attaches to the innermost meningies.
pia mater
surface of brain
trabecule
prevent inflation of brain.
“Spider web looking”
pia to trabecule
Describe cerebral spinal fluid. whats its function?
water, some ions. glucose. Floats CNS, constantly recycled. 500cc produced per day. 150cc volume.
what produces cerebralspinal fluid
choroid plexus and ventricles.
when you do a spinal tap what fluid is it?
cerebralspinal fluid
hydrocephalus
water on the brain, skull expands. Can be fixed by putting drain.
blockage in cerebralspinal production.
most common in adolescence.
not common in adults.
how much is needed to float brain?
150mL
cerebral spinal fluid is made where?
in ventricles
We have spaces in brain that are filled with cerebral spinal fluid. True or False.
True
how many ventricles do we have in brain?
4
Describe the ventricles.
Located deep in CNS
Filled with CSF
2 Lateral, Third, Cerebral Aquaduct, Fourth
Continuous with Subarachnoid Space
first place you can bleed in brain is where?
Epidera
Arterial blood is low pressure and venous blood is high pressure. True or False.
False.
arterial= high pressure
venous= low pressure
Blood gets into subarachnoid space and there is blood everywhere. “the worse headache of your life”. Bleeding out. Associated with hemmoratc stroke or brain injury.
What type of Hemmorrage?
Suprarchnoid Hemmorage
sub dura is located where
underneath dura.
blood drains from brain into dura. what keeps brain from floating around?
dura sinuses
Outermost layer 2 adhered sublayers: Periosteal: lies against inner skull Meningeal:lies against Arachnoid memb. Dural sinuses lie between layers Dural partitions are double meningeal layers What layer of the brain menengies?
Dura
Arachnoid membrane: Transparent sheet attached to Pia by collagen trabeculae.
Sub-arachnoid space: b/w arachnoid membrane and Pia
filled with CSF
Arteries and veins
What layer of the brain meningies?
Arachnoid membrane
Dura has its own arteries and vessels. True or False.
True
As you get older Dura sticks to the skull. True or False.
True
blood in the space bw periostal duma and the skull.
Epideral Hemitoma
Press on Ocular Motor nerve and you will get a “blown pupil” on the side where mass is. True or False
True
What is the difference between an Epidural and a Subdural Hemotoma?
Epidurals are different from subdurals.
Epidural= could kill you in an hour. EMERGENCY. If you put enough pressure on it its over. (Chronic)
Subdural= low emergency situation, no symptoms, sub clinical. (football players get this from concosions) There brains look like old people brains. (Acute)
Thin sheet attached to surface of CNS
Cannot be removed
pia mater
separates right from left brain.
longitudinal fissure.
Double layer sheets of meningeal dura Extend between major fissures of the brain Support and prevent excess movement Falx cerebri Tentorium cerebelli What is this?
dural partitions
Venous passages between dural layers
Drain venous blood from the brain
Receive CSF overflow through arachnoid villi into Superior Sagital Sinus
Drain into Internal Jugular vein
Cavernous sinus surrounds sella turcica, including CN 3,4,6
Cavernous sinus thrombosis, infections
who am I?
Dural Sinuses
Cavernous sinuses are controlled by what arteries?
carotid arteries 3,4, and 6.
Blood in potential space between Periosteal dura and skull
Arterial, high pressure blood
Rapid advance after Traumatic Brain Injury
Increased intracranial pressure
Fixed dilated pupil, papilledema
What type of Hematoma is this?
Epideral Hematoma.
Blood in potential space between meningeal dura and arachnoid membrane
Low pressure venous blood
Slow advance, older patients
Chronic traumatic encephalopathy: athletes alcoholics, elderly.
What type of Hematoma is this?
Subdural Hematoma
Blood in subarachnoid space
Traumatic injury or hemorrhagic stroke
“Worst headache of my life”, sudden onset
what type of Hematoma is this?
Subrarachnoid Hematoma
