Neuro 4 - Anatomy of blood flow in CNS Flashcards
What are the 2 sources of blood supply to the brain?
- Internal carotid arteries
2. Vertebral arteries (posteriorly)
What foramen does the vertebral artery run through?
Transverse foramen of cervical vertebrae
At what level does the carotid artery bifurcate?
At the level of the Adams apple (laryngeal prominence)
On what brain structure does the basilar artery sit?
The pons
Venous drainage of blood in the brain occurs via?
Venous sinuses.
Largest = superior sagittal sinus
What are the 2 types of stroke? What is more common
Infarction (85%)
Haemorrhage (15%)
What is the difference between Transient Ischaemic Attack (TIA) and Stroke?
TIA’s resolve completely in 24 hours, strokes last longer than 24 hours
Name 2 causes of occlusions?
- Thrombi
2. Embolism
What are the RFs for stroke/
- Age
- Hypertension
- Cardiac disease
- Smoking
- T2DM
What are the symptoms of an anterior cerebral artery stroke?
- Paralysis of contralateral leg (more than arm/face)
- Disturbance of intellect, executive function and judgement
- Loss of appropriate social behaviour
Symptoms of stroke of middle cerebral artery
- Contralateral hemiplegia (arm > leg)
- Hemianopia
- Aphasia (L sided lesion)
- Contralateral hemisensory deficits
Symptoms of stroke to posterior cerebral artery
- Visual deficits - homonymous hemianopia / visual agnosia (ability to actually recognise objects after seeing them)
What is a lacunar infarct?
Small cavities that arise in deep structures of the brain due to small vessel occlusions. Deficit depends on anatomical location - may / may not be clinically relevant. Associated with hypertension
Why do subdural haemorrhages have delayed effects?
Because they are lower pressure, venous bleeds
What are the 4 types of haemorrhagic stroke
- Extradural - trauma, immediate onset
- Subdural - trauma, delayed onset
- Subarachnoid - ruptured aneurysm
- Intracerebral - spontaneous hypertensive
