Occipital pole

The backmost part of the occipital lobe is called the occipital pole.

On the inner surface of the occipital lobe, the visual fields from the retina are arranged in a specific way: the outer part of the visual field is represented towards the front, while the central part is represented towards the back. The most central area of the visual field, known as the macula, is represented at the occipital pole on the inner surface. Strokes that affect the posterior cerebral artery (PCA)–the main artery supplying the occipital lobe–can cause a condition called left homonymous hemianopia, where there are visual deficits on the opposite side of the affected hemisphere (for example, left homonymous hemianopia can occur in strokes affecting the right PCA). However, it’s worth noting that, on the medial side, the posterior most part of occipital lobe, called the occipital pole, receives additional blood supply from the middle cerebral artery (MCA). The artery extends from lateral surface of the brain and reaches the medial side. Because the MCA supplies blood to the macular region, even when a PCA stroke occurs, the central region of our vision, known as the macula, is usually unaffected. This condition is called contralateral homonymous hemianopia with macular sparing, and it represents a natural protective mechanism for preserving our central vision.