Ch 1: Clinical Correlates pg 12-20

Question 1

what causes a stroke and what general deficits result?

Answer 1

ischemia or infarction of brain tissue–>sudden onset of neurological deficits

Question 2

what are common causes of a hemorrhagic stroke?

Answer 2

1. subarachnoid hemorrhage (SAH) from blood leaking from berry aneurysm
2. arteriovenous malformation (AVM)

Question 3

what symptoms are associated with berry aneurysms?

Answer 3

• blood released from an aneurysm accumulates in the subarachnoid space and irritates the meninges–>headaches, increased intracranial pressure, vomiting, altered level of consciousness
• CN II and III commonly compressed

Question 4

where do berry aneurysms most commonly occur?

Answer 4

branch points of Circle of Willis (85% AComm and ACA, PComm and internal carotid, superior/inferior divisions of MCA)

Question 5

what is an ischemic stroke?

Answer 5

vascular occlusion without hemorrhage (80% of strokes)

Question 6

what are common causes of ischemic strokes?

Answer 6

thrombus or embolus or from systemic hypoperfusion

Question 7

what are symptoms associated with a thrombus in the anterior circulation?

Answer 7

weakness or sensory loss in the contrlateral upper limb, lower limb, or face, which may be combined with aphasia, apraxia or agnosia

Question 8

what are symptoms associated with a thrombus in the posterior circulation?

Answer 8

weakness or sensory loss in the contralateral upper limb, lower limb, or face, which may be combined with CN signs, gait ataxia, or hemanopsia

Question 9

an embolus in the MCA can result in what symptoms?

Answer 9

weakness or sensory loss in the contralateral upper limb or face, and may have aphasia, apraxia or agnosia depending on which hemisphere/branch

Question 10

an embolus in the posterior circulation can result in what symptoms?

Answer 10

CN signs, gait ataxia, or hemianpsia

Question 11

what causes a water-shed infarct? where do they occur? what symptoms do they cause?

Answer 11

• sudden occlusion/rise in systemic arterial pressure of an internal carotid artery–>unilateral ischemia or infarction in an MCA-ACA watershed area
• weakness and sensory deficits in the arm and shoulder, sensory deficits in the trunk (MCA) and weakness in thigh muscles and sensory deficits in the thigh (ACA)

Question 12

what is a lacunar stroke and what causes it?

Answer 12

ischemia stroke that involve deep small branches of the anterior or posterior circulation

most commonly results from progressive weakening or narrowing of a deep branch of a cerebral artery in patients chronic hypertension or diabetes mellitus

Question 13

what structures do lacunar strokes most commonly affect? what are associated symptoms?

Answer 13

basal ganglia, thalamus, internal capsule, ventral pons or midbrain

contralateral hemiparesis, contralateral hemianesthesia, or both

aphasia, apraxia, agnosias are uncommon

Question 14

what is a transient ischemic attack?

Answer 14

results from temporary occlusion of a branch of a cerebral artery which last less than an hour (typically <10 min)

if longer can cause infarction and permanent neurological defects

Question 15

what commonly causes a TIA?

Answer 15

small emboli that arise from a thrombus and may precede a thrombolytic or embolitis stroke

Question 16

what common symptoms are TIAs associated with?

Answer 16

• if emboli form internal carotid plaque–>retina branches of ophthalmic artery (first branch of internal carotid) commonly involved
• amaurosis fugax= transient blindness on affected side, like a “window shade” going down over eye

Question 17

what arteries that supply the spinal cord are more susceptible to stroke and why?

Answer 17

• anterior spinal vascular territories of thoracic cord segments
• posterior spinal arteries have more potential anastomoses

Question 18

what symptoms result from a patient who has disrupted the radicular contributors to the anterior spinal artery at thoracic spinal cord segments?

Answer 18

bilateral weakness in lower limbs, bilateral pain and temperature loss in lower limbs, loss of bladder and bowel control