Blood supply to the brain Flashcards
What does the opthalmic artery supply? Which other artery does it connect to?
Supplies- Orbit and retina
Connects to external carotid artery
What does the posterior communicating artery connect?
Connects carotid and vertebral artery system
What does the middle cerebral artery supply? Which other 2 arteries anastamose with it?
Basal ganglion,internal capsule 2/3 of the cortex
Anastomoses with anterior and posterior cerebral arteries
What does the anterior cerebral artery supply?
Internal capsule
medial side of frontal and parietal lobe
What does the vertebral artery supply?
Spinal cord
Dorsal medulla of brain stem
What does basilar artery supply?
Pons and cerebellum
What does the posterior cerebral artery supply?
Inferior and medial aspects of temporal and occipital cortex
Thalamus and posterior internal capsule
Midbrain
How many people have a classic circle of willis?
34.5%
Which arteries supply the cerebral cortex?
Anterior, middle and posterior cerebral arteries
What are the main branches in the posterior circulation?
Vertebral, basilar and posterior cerebral
What are some of the major causes of stroke?
AF/atrial enlargement Atherosclerosis Hypertension Aneurysm Elderly Head injury (trauma) Alcoholics Arteriovenous malformation
What are the 3 types of cerebral aneurysms?
Saccular
Fusiform
Berry
What is a transient ischemic attack?
Temporary disruption of blood supply to the brain
Temporary loss of brain function (<30 mins)
Sudden onset but resolves within 24 hrs
Warning sign of heart attack or stroke
What are the symptoms of a transient ischemic attack in the anterior and posterior circulation?
-Anterior circulation Motor weakness Hemi-sensory loss Dysarthria Transient monocular blindness
-Posterior circulation Vertigo Diplopia Ataxia Amnesia Dysphasia
What are the symptoms of cortical stroke, what are the signs of cortical stroke?
Symptoms-
Contralateral paralysis
anaesthesia of face and arm
Can mimic lacunar strokes
Signs- Aphasia Visuospatial neglect Gaze deviation Visual field defects
What is a Lacunar (subcortical) Stroke? What are the symptoms of Lacunar (subcortical) Stroke?
A stroke that affects the deep structures in the brain
Basal Ganglia, thalamus, Internal Capsule (descending motor fibres)
What are the consequences of a stroke in the medial cerebral artery? Names of conditions if it happens in left or right hemispher.
Sensorimotor loss on contralateral face, upper limb and trunk if in Dominant hemisphere (Left) Global aphasia if in Non-dominant (R.parietal lobe) Neglect syndrome
What are the consequences of a stroke in the anterior cerebral artery?
- Contralateral sensorimotor loss below waist
- Urinary incontinence
- Personality defects
- Split-brain syndrome
What are the consequences of a stroke in the posterior cerebral artery?
Contralateral homonymous hemianopsia
Reading and writing deficits
Impaired memory
What is Lateral medullary syndrome? What are the symptoms?
A condition that develops due ischemia in the vertebral arteries and in the posierior inferior cerebella artery
Symptoms- Horner syndrome
Vertigo, nystagmus, nausea and vomiting, dysarthia, dysphonia, loss of pain and temp in body (contralateral), loss of pain and temp in face (ipsilateral), loss of gag reflex (nucleus ambiguus)
Describe the main symptom of a Classic paralytic stroke
– contralateral hemiplegia
Paralysis occurring on the side of the body opposite to the side of the brain in which the causal lesion occurs.
List the classic signs of a stroke
Slurred speech
Inability to raise both arms and keep them there
Face drooping on one side
