WASHINGTON – Aura with migraine seems to be a heterogeneous phenomenon, with up to 40% of patients in a prospective cohort reporting color as a component of the visual manifestation.
Dr. Deborah Friedman, a professor of ophthalmology and neurology at the University of Rochester (N.Y.), discussed results of an observational study of 122 subjects with migraine and aura at the meeting. They were surveyed about the characteristics of their visual symptoms and asked to draw their aura. The surveys were carried out at the university and at a clinic in Florianópolis, Brazil, during 2009-2010. Most (102) were women.
A majority of the patients (83%) were diagnosed as having typical aura with migraine. Another 9% had typical aura with nonmigraine headache. Others had had aura without headache (5%) or aura with probable migraine (3%).
In additional to visual symptoms, about 33% of the group also had other types of aura, including sensory, speech disturbance, motor symptoms, dizziness, and olfactory sensations.
“About 40% reported that they always experience aura with all of their headaches,” Dr. Friedman said. Another 40% reported that aura occurred with fewer than half of their headaches, and 20% said aura accompanied more than half of their headaches.
Auras started early in the headache history for most patents – 61% said the symptom appeared within the first year of having migraine.
The phenomenon begins in different fields of vision and different locations in relation to the region of pain.
“In about half, the aura starts in the peripheral visual field and in 45%, centrally. Only 5% said the aura clearly began in one hemifield of the vision.” Most auras were unilateral (75%). But 8% of patients said their aura always occurred on the contralateral side of a unilateral headache.
Motion was a common feature. “We tend to think about aura as moving across the visual field. In 57% of our group, this was true, with the aura moving from the center to the periphery in 48% and from the periphery to the center in the rest of the patients.” Most (67%) also reported a shimmering quality to the aura.
Timing was variable, Dr. Friedman said. “Most patients experienced aura before the onset of headache, with 65% reporting it less than 30 minutes before.” But 15% said it could occur up to 4 hours before a headache, and 20% said the two occurred simultaneously.
Color was a component of 40% of aura, with 18% of patients reporting their auras as always colorful. The majority also reported blurred vision as part of the phenomenon.
Other characteristics included small bright dots, zigzag lines, and crescent or C-shaped manifestations. Less often, patients reported bright flashes, blind spots, flickering lights, “heat wave” shimmer, partial loss of vision, colored or white spots, and corona.
Patients' drawings of their aura show small bright dots, zigzag lines, crescent or C-shaped manifestations, mosaic patterns, round forms, and tunnel vision.
Source Images courtesy Dr. Deborah Friedman