What supplies the posterior circulation?
posterior cerebral artery
What supplies the anterior circulation?
- anterior cerebral artery
- middle cerebral artery
What is the Circle of Willis made of?
- middle cerebral arteries
- anterior cerebral arteries
- anterior communicating artery
- posterior communicating artery
- posterior cerebral artery
What supplies the deep forebrain (basic)?
small arteries off the circle of willis
What supplies 2/3 of the spinal cord?"
branches off the anterior spinal artery
What supplies 1/3 of the spinal cord?
branches off the posterior spinal artery
What is a transient ischemic attack?
brief, focal loss with full recovery in 24 hours
What is a completed stroke?
stable neuro deficits that persist more than 1 day
What is a progressive stroke?
deficits that progress over time
What is a brain infarct and the three different types?
- obstruction of blood flow
- emobolus, thrombus, lacunar infarct
What is an embolus?
- moving clot that abruptly blocks blood flow
- usually immediate deficits
What is a thrombus?
- stationary clot
- deficits can be immediate or slowly progressive
What is a lacunar infarct?
- usually in deep forebrain structures with cavity remaining after necrotic tissue remove
- slow onset with good prognosis for recovery
What is a hemorrhage?
- bleeding within the brain
- damage from blood, edema, cytotoxic events and distal ischemia
What is a subarachnoid hemorrhage?
- bleeding in the subarachnoid space
- damage from increased pressure, herniation, vasospasm, and infarction
What is AV Malformation?
developmental deficit with thin capillaries connecting arteries and veins
What is an aneurysm and the two different types?
- dilation in the vascular wall
- saccular: dialation of 1 side of the vascular wall
- berry: thin connecting stalk with vessel
How does the blood flow through the brain (big picture)?
blood flow to the brain is drained through the dural venous sinus system and returns to circulation through the internal jugular vein
How does the CSF flow through the brain (big picture)?
- CSF is produced in choroid plexes of ventricles
- circulates through ventricles and into cisterns through foramina of luschka and magendie
- CSF bathes and protects outer surface of CNS and flow toward arachnoid granulations
- passes through arachnoid granulations to enter the dural venous sinus system
What are the three layers of meninges?
- dura mater
- pia mater
What are the two layers of the dura mater?
- external layer- periosteal layer: firmly attached to bone w/in cranial cavity
- internal layer- meningeal layer
Where are the meningeal arteries?
within the dura between the periosteal and meningeal area
What is the falx cerebri?
lies between the cerebral hemispheres
What is the tentorium cerebelli?
- divides cranial cavity into upper and lower 1/2
- aka cerebellar roof
What is the falx cerebelli?
- separates hemispheres of the cerebellum
- right and left side
What are the dural sinuses?
- contain venous blood and CSF
- dura mater forms the walls
- drains toward the internal jugular vein