Which statement about the hippocampus is true?

• A. It receives its arterial supply from the posterior cerebral artery territory.
• B. It is exclusively supplied by the middle cerebral artery.
• C. It is not affected in MTLE.
• D. It has no vascular supply.

Answer: (A)

The vascular supply to the hippocampus is the main idea here. The hippocampus sits in the medial temporal lobe and is primarily nourished by branches of the posterior cerebral artery. Posterior hippocampal arteries from the PCA (with perforators from the posterior choroidal arteries) deliver the blood that perfuses the hippocampal formation, including the CA fields and dentate gyrus. There is some contribution from the anterior choroidal artery to the anterior aspect, but the dominant supply comes from the PCA territory.

This makes the statement about PCA territory being the blood source correct. The middle cerebral artery mainly nourishes the lateral aspects of the temporal lobe and cortical areas, not the hippocampus as its primary source, so claiming exclusive MCA supply isn’t accurate. Regarding MTLE, the hippocampus is commonly involved in mesial temporal lobe epilepsy with sclerosis, so saying it isn’t affected is not correct. And like any brain structure, the hippocampus does have vascular supply; the idea that it has none is false.