Anatomy, Physiology, and Pathophysiology of Stroke Flashcards

Which cerebral artery supplies the lateral surface of the frontal and parietal lobes, including the primary motor cortex of the upper extremity?

Answer: Middle cerebral artery

The middle cerebral artery (MCA) supplies the lateral hemispheres including the motor and sensory cortex for the face, arm, and hand.

A patient presents with bilateral leg weakness and urinary incontinence after a stroke. Which artery territory is most likely affected?

Answer: Anterior cerebral artery

The anterior cerebral artery (ACA) supplies the medial hemisphere including the leg area of the motor cortex; bilateral ACA involvement causes bilateral leg weakness and incontinence.

During cerebral ischemia, the ischemic penumbra is best defined as:

Answer: Hypoperfused but potentially viable tissue surrounding the infarct core

The ischemic penumbra is electrically silent but metabolically viable tissue surrounding the infarct core that can be salvaged with timely reperfusion.

Which ion flux occurs first during the depolarization phase of ischemic neuronal injury?

Answer: Sodium influx

During ischemic depolarization, failure of the Na⁺/K⁺-ATPase pump leads to massive sodium influx, followed by water entry and cytotoxic edema.

Lacunar infarcts are most commonly caused by:

Answer: Lipohyalinosis of small penetrating arteries

Lacunar infarcts result from lipohyalinosis or microatheroma of small penetrating arteries (< 15 mm diameter), most commonly in the basal ganglia, thalamus, and internal capsule.

A 58-year-old patient develops sudden onset diplopia, dysphagia, and ipsilateral facial numbness with contralateral body numbness. Which syndrome does this represent?

Answer: Wallenberg (lateral medullary) syndrome

Wallenberg syndrome results from posterior inferior cerebellar artery occlusion causing ipsilateral facial and contralateral body pain/temperature loss, dysphagia, dysarthria, and Horner syndrome.

Which mechanism accounts for the majority of hemorrhagic strokes in elderly hypertensive patients?

Answer: Hypertensive lipohyalinosis with vessel rupture

Chronic hypertension causes lipohyalinosis of small penetrating vessels, making them prone to rupture and causing intracerebral hemorrhage, typically in the basal ganglia, thalamus, pons, or cerebellum.