Anterior cerebral artery (ACA) infarct

Anterior cerebral artery (ACA) territory infarcts are much less common than either middle or posterior cerebral artery territory infarcts.

Epidemiology

ACA territory infarcts are rare, comprising ~2% of ischemic strokes ^1,2.

Clinical presentation

ACA stroke syndrome presents as ^1-3:

• dysarthria, aphasia
• unilateral contralateral motor weakness (leg/shoulder > arm/hand/face)
• minimal sensory changes (two-point discrimination) in the same distribution as above
• left limb apraxia
• urinary incontinence

Pathology

ACA territory infarcts are less common because if the A1 segment is occluded there is generally enough collateral flow via the contralateral A1 segment to supply the distal ACA territory ².

Embolic strokes (often with MCA involvement) are the most common cause ³. Rarely, they are also seen as a complication of severe midline shift, where the ACA is occluded by mass effect or severe vasospasm.

Radiographic features

The features are those of cerebral infarction in the anterior cerebral artery vascular territory:

• paramedian frontoparietal cerebral cortex
• anterior corpus callosum
• anterior limb of the internal capsule
• inferior portion of the caudate head

Differential diagnosis

• watershed infarct
• cerebral venous infarct