Some patients may report only the visual symptomatology of migraine aura without any associated headache. The occurrence of visual symptoms of migraine without headache (acephalgic migraine; 5% of migraine) must be differentiated from transient ischemic attacks (TIAs). Visual migraine equivalents include scintillating scotomata, transient homonymous hemianopia without positive visual phenomena, peripheral visual field constriction progressing to tunnel vision or complete visual loss, transient monocular visual loss, and episodic diplopia (usually vertical and accompanied by other neurologic symptoms). Symptoms typically last less than 60 minutes and tend to develop and remit progressively during that time. A positive patient history or family history of migraine with aura is helpful for the diagnosis, as is a description of the deficit. The classic scintillating scotoma with fortification spectrum is suggestive of migraine. Residual visual field defects may indicate another underlying process, such as cerebrovascular disease or a vascular malformation.
Often attributed to migraine, vasospasm may, less commonly, affect only 1 eye (sometimes referred to as retinal migraine), resulting in monocular visual loss. Transient retinal opacification and narrowing of the retinal arterioles may be seen during symptomatic episodes in some patients.
, KupersmithMJ, WirtschafterJD, FormanS. Brief report: treatment of vasospastic amaurosis fugax with calcium-channel blockers.1993;329(6):396–398.