Blood Supply to the Brain (Yr 2 Lecture) Flashcards
Describe the nature of anterior communicating and posterior communicating arteries under normal conditions [1]
Under normal situations anterior communicating and posterior communicating CLOSED
Normal arterial supply in brain
Most intracerebral strokes effect which artery in the brain? [1]
Which artery coming off this artery are commonly effected? [1]
MCA - causes lenticulostriate arteries to have common strokes
What are watershed areas in the brain? [1]
Watershed areas: where ACA & MCA anastomose
Label A-G
Superficial venous drainage
Which veins drain from cerebral cortex into the venus sinuses? [1]
Describe their path x
Superficial cerebral veins
* Cross the subarachnoid space & pierce the dura
(confirm !)
Which two fluids drain into the venous sinuses? [2]
Blood from superficial cerebral veins
CSF - from arachnoid granulations
State the veins from blue & red arrow [2]
Red arrow = vein of Trolard (superior anastomotic vein)
Blue arrow = vein of Labbe (inferior anastomotic vein)
What are the two types of strokes [2] & their causes [2]
Ischaemic (thrombotic; embolic): 80%
Haemorrhagic stroke (trauma; spontaneous): 20%
Label the blood supply impacted by these hemorrhagic stroke
A = cortical branches of ACA, MCA or PCA
B = ascending lenticulostriate arteries of MCA
C = thalamogeniculate of PCA
D = paramedian branches of basilar artery
E = branches of AICA, SCA and PICA
Name the leading causes of hemorrhagic stroke [5]
Major causes of hemorrhagic stroke
* Hypertension
* Aneurysm
* Elderly
* Head injury (trauma)
* Alcoholics
* Arteriovenous malformation
Label type of stroke in this diagram
What are the two leading causes of non-traumatic hemorrhagic stroke? [2]
HTN
Aneursym
Describe MCA stroke if occurs on the:
- Left
- Right
MCA Left stroke
* Global aphasia
* Sensorimotor loss on contralateral face, upper limb and trunk
Right MCA Stroke:
* Neglect syndrome
Which artery is effected here? [1]
Lenticulostriate
Describe the effect of ACA stroke [4]
- Contralateral sensorimotor loss below waist
- Urinary incontinence
- Personality defects (start off as apathetic: replaced by impulsivity)
- Split-brain syndrome
Split brain syndrome
Describe how a patient with split brain syndrome would percieve & verbalise an object in their right visual field & their right hand
Describe how a patient with split brain syndrome would percieve & verbalise an object in their left visual field & their left hand
Human anatomy; the right hemisphere receives visual input from the left visual field and controls the left hand
right visual field the patient responds correctly verbally and with his/her right hand.
Left visual field the patient verbally states that he/she saw nothing, and identifies the object accurately with the left hand only
Describe the effects of PCA stroke [3]
- Contralateral homonymous hemianopsia (a field loss deficit in the same halves of the visual field of each eye,)
- Reading and writing deficits
- Impaired memory
Why is split brain syndrome caused by ACA stroke [1]
Corpus callosum supplied by ACA and connects L&R
Define TIA [1]
What is TIA a warning sign for? [2]
A transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retina ischemia, without acute infarction
Warning sign for heart attack of stroke
Why do TIAs commonly present with temporary blindness? [1]
Opthalmic artery
What are the 3 types of extra-axial bleed? [3]
Subdural hematoma (SDH)
Epidural (extradural) hematoma
Subarachnoid hematoma
Which type of intra-axial bleed causes the most mortality? [1]
Which type of veins are commonly ruptered to cause this? [1]
Subdural hematoma - due to bridging veins rupturing
Which arteries are commonly affected during extradural (epidural) hematoma? [2]
Middle meningeal Artery(temperoparital area, pterion)
Ant. Ethmoidal A. (frontal)