The favored explanation for why the center visual field is preserved after large hemispheric lesions is that the macular regions of the cortex have a double vascular supply from the middle cerebral artery (MCA) and the posterior cerebral artery (PCA). If there is damage to one vascular pathway, like in the case of a MCA or PCA stroke, there is still another blood supply that the macular portions of the visual cortex can rely on. Vision in the center of the visual field is then preserved whereas vision in peripheral areas is lost due to the resulting infarct. Another possible reason is that the maculae project to both hemispheres, so in the event of a lesion in one hemisphere, the other intact hemisphere will still receive and process visual information from the maculae in both eyes.
Macular sparing
Macular scarring
Macular edema
Progressive retinal atrophy
Tunnel vision
Optic disc pallor
Optic disc drusen
Macular hypoplasia