Migraine

  • Episodic headache often preceded by neurologic manifestation called "aura"
  • Most common aura: sparkling zigzag that migrates across visual hemifield and obscures it ("scintillating scotoma")
  • Visual aura starts as tiny scotoma appearing to both eyes adjacent to fixation
  • Scotoma enlarges across one hemifield with sparkling leading edge, blocking vision as it goes
  • Visual episode lasts 20 to 30 minutes
  • Headache, fatigue, nausea, mild confusion follow visual aura and last for hours to days
  • Visual aura may occur without other manifestations ("acephalgic migraine"), especially after age 50
  • Posterior circulation (vertebrobasilar) transient ischemic attack (TIA), but episode lasts seconds to minutes and scotoma does not migrate
  • Occipital lobe seizure, but duration of visual symptoms very variable and scotoma does not migrate
  • Vitreoretinal tug, but visual symptom is non-migrating flash lasting less than second
  • Retinal or optic nerve disorders, but visual symptom usually flickering lights
  • Consider alternative diagnoses if symptoms do not match migraine perfectly
  • Refer to ophthalmologist, who may refer patient to neurologist or internist, depending on findings
  • Advise patients with migraine and visual aura to avoid smoking and oral contraceptives, which increase risk of migrainous stroke
  • Recognize difficulty of excluding TIA or seizure, which are potentially life-threatening
  • Migraine may be disruptive if attacks frequent and painful, requiring medication