Subfalcine herniation compresses which artery?

• A. Anterior cerebral artery
• B. Middle cerebral artery
• C. Posterior cerebral artery
• D. Basilar artery

Answer: (A)

Subfalcine herniation occurs when the cingulate gyrus herniates underneath the falx cerebri due to increased intracranial pressure. In this position, the cingulate gyrus can press on the anterior cerebral artery as it travels in the interhemispheric fissure, making the anterior cerebral artery the most vulnerable vessel. The ACA supplies the medial portions of the frontal and parietal lobes, so its compression can cause contralateral leg weakness and behavioral or personality changes from involvement of the medial frontal regions. The middle cerebral artery lies laterally and is more at risk in other herniation patterns (like uncal herniation), while the posterior cerebral and basilar arteries are not typically affected by subfalcine herniation.