Visual field losses in subjects with migraine headaches

PURPOSE. To characterize the visual fields of subjects with migraine headac hes using static and temporal modulation perimetry. METHODS. Sixteen subjects with migraines (15 with aura, 1 without) and 15 n onheadache controls were tested. Perimetry was conducted 7 days after the o ffset of a headache with both static and temporally modulated targets using the Medmont M-600 automated perimeter (Medmont Pty Ltd., Camberwell, Victo ria, Australia). Flicker thresholds were measured using the autoflicker tes t, which varies flicker rate with eccentricity. A subset of four subjects w ith migraines (3 with aura, 1 without) had the temporal tuning characterist ics of their loss evaluated using fixed temporal frequencies (4, 6, 9, 12, and 16 Hz). RESULTS. Field losses were identified with temporal modulation perimetry in 11 of 16 migraine subjects. The majority of these losses occurred in the p resence of normal static thresholds (8/11). The deficits displayed temporal tuning, being greatest for higher temporal frequencies (greater than or eq ual to 9 Hz). None of the subjects revealed deficits typical of cortical le sions. The migraine-without-aura subject displayed a selective loss to temp orally modulated stimuli, which was consistent with the aura group. This de fect altered over time, decreasing for 30 to 40 days but remaining, to a sm aller extent, for up to 75 days after the headache event. CONCLUSIONS. Visual dysfunction that is selective for temporally modulated targets occurs in migraine subjects. The migrainous pattern of dysfunction shares some features with that identified in early stages of glaucoma and r aises the possibility for a common precortical vascular involvement in thes e two conditions.