Acute Thalamic Lacunar Infarction

Definition and Pathophysiology

Lacunar infarcts are subcortical strokes measuring <1.5 cm in diameter on CT or MRI without evidence of cortical involvement, primarily caused by small vessel disease affecting penetrating arteries deep in the brain, as stated by the American College of Cardiology 1, 2
The pathophysiology differs from other stroke subtypes: lacunar infarcts are generally not caused by atherosclerosis but rather by a distinct arteriopathy of small vessels, often related to chronic hypertension or diabetes, according to the American Heart Association 2, 3

Diagnosis requires neuroimaging (CT or MRI) showing a small (<1.5 cm) subcortical infarct in the thalamus, with MRI being more sensitive than CT for detecting acute lacunar infarcts, as recommended by the American College of Radiology 1, 2, 4
MRI with diffusion-weighted imaging (DWI) is the preferred modality for detecting acute thalamic lacunar infarction, as it can identify small acute ischemic lesions that may be missed on CT, according to the American College of Radiology 4

Among stroke subtypes, patients with small-artery (lacunar) occlusion have the highest survival rate at 85% at 2 years, making this the most favorable stroke subtype prognostically, as reported by the American Heart Association 1, 2, 3

Standard acute stroke management protocols apply, with antiplatelet drugs used for secondary prevention, as stated by the American College of Cardiology 1