How do lacunar strokes typically present, and what underlying pathology commonly causes lacunar infarcts?

• A. Lacunar stroke often causes pure motor or pure sensory deficits; cortical strokes cause aphasia or neglect; lacunar infarcts are commonly due to lipohyalinosis from hypertension/diabetes.
• B. Lacunar stroke presents with aphasia; cortical strokes present with neglect.
• C. Lacunar infarcts are caused by emboli from the heart.
• D. Lacunar strokes affect only the visual field.

Answer: (A)

Lacunar strokes come from small-vessel disease affecting deep penetrating arteries, most often due to lipohyalinosis from long-standing hypertension and diabetes. This leads to small, deep infarcts in areas like the internal capsule, thalamus, or brainstem. Because these strokes involve deep, subcortical structures rather than the cortex, the typical presentation is a pure motor deficit (weakness on one side) or a pure sensory deficit (numbness), without the higher-order cortical signs you’d expect from cortical strokes.

Cortical strokes, which involve the brain’s outer layer, more often produce aphasia, neglect, or other cortical deficits because they affect language, attention, and other complex functions. Embolic or large-vessel causes tend to produce cortical symptoms and larger areas of damage, not the classic pure motor or sensory lacunar syndromes. Occipital or visual-field deficits point to posterior circulation or occipital cortex involvement, not lacunar deep-structure disease.

So the best description is that lacunar strokes typically present with pure motor or pure sensory deficits, and lacunar infarcts are commonly due to lipohyalinosis from hypertension and diabetes.