Migraine with binocular blindness: A clinic-based study

Objective.â To describe the syndrome of migraine with binocular blindness. Background.â Rarely do migraine patients complain of losing vision in both eyes during an attack of headache. There are no large clinic-based studies looking at the prevalence of binocular blindness in migraine sufferers and no information about patient demographics, neuroimaging, and laboratory testing. Methods.â Over a 14-month time period, 383 new patients with a diagnosis of migraine were seen at the Geisinger Headache Center. All patients were asked if they ever experienced an episode of complete bilateral blindness along with their headaches. Those with a positive history had coagulopathy testing as well as brain magnetic resonance imaging and magnetic resonance angiography of the intracranial circulation. Results.â A total of 6 patients or only 1.6% of the new migraine patients had episodes of binocular blindness with their headaches. All were female and each had a history of migraine for at least 3 years. Five patients had a diagnosis of migraine without aura, while one had a diagnosis of basilar-type migraine. In all patients the blindness episodes occurred in isolation during a migraine headache. In all but one patient the blindness was instantaneous and not a slow evolution. In 2 patients the blindness episode only occurred 1 time; in 3 patients episodes occurred more than once but were rare, while 1 patient had blindness with 50% of her headaches. In regard to duration, in 2 patients blindness lasted only several seconds, 2 patients between 2 and 10 minutes, 1 patient 30 minutes and 1 patient 60-120 minutes. Neuroimaging was normal in all. Three patients had a history of smoking and 3 never smoked. Coagulopathy testing was abnormal in all patients. Two patients were homozygous for methylenetetrahydrofolate reductase (MTHFR) 677TT polymorphism, but both had normal homocysteine levels; 3 patients were heterozygous for MTHFR 677CT polymorphism and 1 had elevated homocysteine levels and 1 patient had a positive lupus anticoagulant (had the most frequent episodes of blindness). Conclusion.â Binocular blindness with migraine headache is a very rare occurrence at least in a headache specialty clinic population. It is a female-predominant event and occurs mostly in migraine patients who do not have a history of aura. Blindness episodes can be very brief or prolonged and many do not fit the typical duration of a migraine aura. They are typically infrequent events and may occur only 1 time without recurrence. Migraine with binocular blindness may reflect an underlying clotting disorder. A possible etiology outside of a coagulopathy-related event is retinal spreading depression.