Stroke

Question 1

Principles of neuroplasticity

Answer 1

1. Use It or Lose It: Failure to drive specific brain functions can lead to functional degradation.
2. Use It and Improve It: Training that drives a specific brain function can lead to an enhancement of that function.
3. Specificity: The nature of the training experience dictates the nature of the plasticity.
4. Repetition Matters: Induction of plasticity requires sufficient repetition.
5. Intensity Matters: Induction of plasticity requires sufficient training intensity.
6. Time Matters: Different forms of plasticity occur at different times during training.
7. Salience Matters: The training experience must be sufficiently salient to induce plasticity.
8. Age Matters: Training-induced plasticity occurs more readily in younger brains.
9. Transference: Plasticity in response to one training experience can enhance the acquisition of similar behaviors.
10. Interference: Plasticity in response to one experience can interfere with the acquisition of other behaviors.

Question 2

ACA is the first and smaller of two terminal branches of the ____ _____ artery

Answer 2

internal carotid

Question 3

ACA supplies the ______ aspect of the cerebral hemisphere (frontal and parietal lobes)

Answer 3

medial

Question 4

The medial aspect of the cerebral hemisphere are frontal and parietal lobes and subcortical structures including basal ganglia (anterior internal capsule, inferior caudate nucleus) anterior fornix and anterior four-fifths of the corpus callosum. T or F

Answer 4

True

Question 5

Because the anterior communicating artery allows perfusion of the proximal ACA from either side, occlusion proximal to this point results in minimal deficit T or F

Answer 5

T

Question 6

The MCA is the second of the two branches of the internal carotid artery and supplies the entire _______ aspect of the cerebral hemisphere

Answer 6

lateral

Question 7

The internal carotid artery ICA usually produces infarction in the region of the brain supplied by the MCA. The ICA supplies both the ______ and the ______.

Answer 7

MCA ACA

Question 8

If collateral circulation to the ACA from the circle of Willis is absent, extensive cerebral infarction in the areas of both the ACA and MCA can occur. ICA supplies both the MCA and the ACA.

Answer 8

True

Question 9

The two posterior cerebral arteries (PCA) arise as terminal ranges of the ______ artery

Answer 9

basilar

Question 10

each PCA supplies the corresponding occipital lobe and medial and inferior lobe

Answer 10

yup, each PCA supplies the occipital lobe and medial and inferior lobe annnnd brainstem midbrain and posterior diencephalon, including most of the thalamus

Question 11

occlusion proximal to the posterior communicating artery usually results in ______ deficits owing to the collateral blood supply from the PCA (similar to ACA syndrome)

Answer 11

minimal

Question 12

occlusion of thalamic granges may produce hemianesthesia which is

Answer 12

contralateral sensory loss or central poststroke thalamic pain

Question 13

occipital infarction produces homonymous hemianopia, known as _______ _______, prosopagnosia, or if Bilateral, cortical blindness.

Answer 13

Visual agnosia

Question 14

temporal lobe ischemia results in ______

Answer 14

amnesia (memory loss)

Question 15

subthalamic branches may involve the subthalmic nucleus or is pallidal connections, producing a _____ variety of deficits

Answer 15

wide

Question 16

Contalateral hemiplegia occurs with involvement of the _________ peduncle

Answer 16

cerebral

Question 17

FAST

Answer 17

Face drooping
Arm weakness
Speech difficult
Time to call 911

Question 18

Ischemic Stroke

Answer 18

Ischemic stroke is the most common type, affecting about 80% of individuals with stroke, and can be the result of a thrombosis, embolism, or hypoperfusion. A thrombus is a local occlusion of a blood vessel, and an embolus is material from a distant site that either blocks or impairs blood flow, depriving the brain of essential oxygen and nutrients.

Question 19

Hemorrhagic Stroke

Answer 19

Hemorrhagic stroke occurs when blood vessels rupture, causing leakage of blood in or around the brain. Much more life threatening due to ICP resulting in midline shift and pressure related damage. Impairments may resolve spontaneously as brain swelling subsides (reversible ischemic neurological deficit), generally within 3 weeks. Residual neurological impairments are those that persist longer than 3 weeks and may lead to lasting disability.

Question 20

Transient Ischemic Attack

Answer 20

Transient ischemic attack (TIA) refers to the temporary interruption of blood supply to the brain. Symptoms of focal neurological deficit may last for only a few minutes or for several hours but by definition do not last longer than 24 hours. After the attack, there may be evidence of residual brain damage or permanent neurological dysfunction. It is therefore recommended that they be considered like acute strokes. TIAs may result from a number of different etiological factors, including occlusive episodes, emboli, reduced cerebral perfusion (arrhythmias, decreased cardiac output, hypotension, overmedication with antihypertensive medications, subclavian steal syndrome), or cerebrovascular spasm. The major clinical significance of TIA is as a precursor to susceptibility for both cerebral infarction and myocardial infarction. The risk for recurrent stroke is 3.5%, 8%, and 9.2% at 2, 30, and 90 days post-TIA respectively.

Question 21

Thrombotic strokes

Answer 21

Cerebral thrombosis refers to the formation or development of a blood clot within the cerebral arteries or their branches. It should be noted that lesions of extracranial vessels (carotid or vertebral arteries) can also produce symptoms of stroke. Thrombi lead to ischemia, or occlusion of an artery with resulting cerebral infarction or tissue death (atherothrombotic brain infarction [ABI]). Thrombi can also become dislodged and travel to a more distal site in the form of an intra-artery embolus.

Question 22

Embolic stroke

Answer 22

Cerebral embolus (CE) is composed of bits of matter (blood clot, plaque) formed elsewhere and released into the bloodstream, traveling to the cerebral arteries where they lodge in a vessel, producing occlusion and infarction. The most common source of CE is disease of the cardiovascular system. Occasionally, systemic disorders may produce septic, fat, or air emboli that affect the cerebral circulation.

Question 23

Hemorrhagic strokes (Intracerebral)

Answer 23

Intracerebral hemorrhage (IH) is caused by rupture of a cerebral vessel with subsequent bleeding into the brain.

Question 24

Subarachnoid hemorrhage (SH)

Answer 24

occurs from bleeding into the subarachnoid space typically from a saccular or berry aneurysm affecting primarily large blood vessels. Congenital defects that produce weakness in the blood vessel wall are major contributing factors to the formation of an aneurysm.

Question 25

Subdural hematomas

Answer 25

which are bleeds between the brain and the dura mater, can cause stroke-like symptoms due to increased pressure and potential blood vessel damage, but they are also a potential complication of stroke itself. Bleeding between the brain and the skull can cause a lot of damage in the brain through ICP.

Question 26

Ruptured cerebral aneurysm

Answer 26

A ruptured cerebral aneurysm, a weakened blood vessel in the brain that bursts, can cause a hemorrhagic stroke, a type of stroke characterized by bleeding in the brain. After a brain aneurysm ruptures, blood vessels in the brain may contract and narrow. This is known as vasospasm. Vasospasm can cause an ischemic stroke, in which there's limited blood flow to brain cells. This may cause additional cell damage and loss.

Question 27

Arteriovenous malformation

Answer 27

Arteriovenous malformation (AVM) is another congenital defect that can result in stroke. AVM is characterized by a tortuous tangle of arteries and veins with agenesis of an interposing capillary system. The abnormal vessels undergo progressive dilation with age and eventually bleed in about 50% of cases. Sudden and severe cerebral bleeding can result in death within hours, because intracranial pressures rise rapidly and adjacent cortical tissues are compressed or displaced as in brainstem herniation.

Question 28

Lacunar strokes

Answer 28

Lacunar strokes are caused by small vessel disease deep in the cerebral white matter (penetrating artery disease). They are strongly associated with hypertensive hemorrhage and diabetic microvascular disease. Lacunar syndromes are consistent with specific anatomical sites. Pure motor lacunar stroke is associated with involvement of the posterior limb of the internal capsule, pons, and pyramids. Pure sensory lacunar stroke is associated with involvement of the ventrolateral thalamus or thalamocortical projections. Other lacunar syndromes include dysarthria/clumsy hand syndrome (involving the base of the pons, genu of anterior limb, or the internal capsule), ataxic hemiparesis (involving the pons, genu of internal capsule, corona radiata, or cerebellum), sensory/motor stroke (involving the junction of the internal capsule and thalamus), and dystonia/involuntary movements (choreoathetosis with lacunar infarction of the putamen or globus pallidus; hemiballismus with involvement of the subthalamic nucleus).

Question 29

Pure motor lacunar stroke

Answer 29

is associated with involvement of the posterior limb of the internal capsule, pons, and pyramids.

Question 30

Pure sensory lacunar stroke i

Answer 30

associated with involvement of the ventrolateral thalamus or thalamocortical projections