lacunar infarct
Pronunciation: LAK-yoo-nar
A small deep brain infarct typically less than 15mm diameter, resulting from occlusion of penetrating arterioles.
Full Definition
Lacunar infarcts are small subcortical ischemic lesions caused by occlusion of single penetrating arterioles that supply deep brain structures including the basal ganglia, thalamus, internal capsule, and brainstem. These infarcts typically measure less than 15mm in diameter and result from lipohyalinosis or microatheroma affecting small perforating vessels. On MRI, acute lacunar infarcts appear hyperintense on diffusion-weighted imaging and may evolve into chronic lacunes - small fluid-filled cavities that appear hypointense on T1 and hyperintense on T2-weighted images.
Usage
Usage note: Specify acute vs. chronic; distinguish from enlarged perivascular spaces.
In Context
- "A new lacunar infarct in the left corona radiata was identified on diffusion-weighted imaging." — Acute stroke report
- "Multiple chronic lacunar infarcts were present throughout the basal ganglia, consistent with chronic small vessel disease." — Vascular dementia assessment