Effects of visual pathway lesions on the visual aura of migraine.

The aim was to to determine if the visual aura of migraine is altered by disease of the afferent visual pathways and if visual aura changes are associated with pre- or postgeniculate lesions. Functional neuroimaging during migraine demonstrates primary visual/extrastriate cortex as an anatomical substrate of visual aura. Neuro-ophthalmological records (including kinetic and static perimetry) of 25 patients with visual loss and typical aura with or without migraine headache were reviewed. Twenty-five patients (16 women, nine men) (mean age 59.8 years) with typical aura had visual loss from pregeniculate (72%) or postgeniculate lesions (28%). Eight patients (four postgeniculate cerebrovascular accidents or arteriovenous malformations, two lifelong optic neuropathy/retinopathy, one childhood ocular trauma, one anisometropic amblyopia) reported absence or alteration of visual aura. Postgeniculate lesions were significantly associated (P = 0.017) with visual aura changes. The association of postgeniculate lesions with altered auras points to a postgeniculate effect on aura appearance (consistent with functional neuroimaging findings). Although statistically significant, this series' association of postgeniculate disease and aura changes is even more robust (P = 0.0002) when structural changes of ocular dominance columns are posited in three patients with optic neuropathy, retinopathy and keratopathy of congenital or childhood origin.