Lecture 3 Flashcards
How much blood circulates to the head?
20-25% of cardiac output each stroke
What two substances does the brain rely on?
glucose and oxygen, only uses amino acids or fatty acids if absolutely necessary
What branch primarily supplies the anterior circulation of the brain?
internal carotid artery
Disease of which artery would be an indicator for disease in the brain?
opthalmic artery
Which artery supplies the lateral convexity of the brain?
middle cerebral artery
In the anterior circulation of the brain, the upper and inferior divisions of the middle cerebral artery supply what areas of the brain?
upper - frontal and parietal lobes; inferior - temporal lobe
Which arteries travel the length of the spinal cord?
anterior and posterior spinal arteries
Which arteries may or may not be present to complete the circle of Willis?
anterior or posteror communicating arteries, if not present you will be more prone to stroke
Which arteries supply irrigation to the pons?
pontine arteries
In the posterior circulation of the brain, which arteries anastomose to form the basilar artery?
vertebral arteries (come through foramen magnum)
The oculomotor nerve lies between which two arteries?
posterior cerebral and superior cerebellar arteries
What are the three meningeal layers covering the brain and spinal cord?
dura, arachnoid, pia
This sinus begins at the Crista Galli and runs to the Inion (external occipital protuberance) through the midline.
superior sagittal sinus
This major vein drains the inside of the brain.
great vein of Galen
This sinus runs in midline straight posteriorly to the Inion, converging with the superior sagittal sinus.
straight sinus
This sinus runs along the falx cerebri (a dural reflection), converges with straight sinus.
inferior sagittal sinus
These sinuses run laterally on both sides of the brain that run to the Inion.
transverse sinuses
What is the confluence of sinuses?
where the superior sagittal sinus, straight sinus, and transverse sinuses all join at the inion
What is the sigmoid sinus?
S-shaped curve the is continuous with internal jugular vein, here there is a change of tissue type: vein (endothelial cells line the inside of veins) and sinus system (fibroblasts)
Which sinus sits on either side of Sella Turcica?
cavernus sinus (facial–>opthalmic vein drain into)
The cavernus sinus provides a direct entry for infection to the brain. What structures could be affected?
oculomotor, trochlear, abducens, and V1 of trigeminal (ophthalmic) can all be directly affected
If the cavernus sinus were infected, what might be some clinical symptoms?
wouldn’t be able to track, affected eye would be dilated, and would have decreased sensation to the forehead