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Migraine Aura Without Headache Donald M B rief Reports Migraine Aura Without Headache Donald M. Pedersen, PA-C, PhD, William M. Wilson, PhD, George L. White, Jr, PA-C PhD Richard T. Murdock, MS/HSA, and Kathleen B. Digre, MD Salt Lake City, Utah Migraine is described as a familial disorder characterized to the disturbance described. The patient also denies by recurrent headaches that are variable in intensity, antecedent trauma or emotional stress. The episodes arc frequency, and duration.1 Attacks are usually unilateral reportedly always similar in nature, with an expanding but can also be bilateral and accompanied by throbbing scintillating scotoma and without subsequent headache, pain, photophobia, phonophobia, nausea, and vomiting. The patient’s first episode, his m ost recent episode, and Some migraines are preceded by, or are associated with, “a few” of the others have occurred after a 60-minutc neurological and mood disturbances. All of the above exercise period, which he performs consistently as a mat­ characteristics, however, are not necessarily present in ter of his daily routine. There is a history of myopia, for each attack, nor in each patient.2 correction o f which soft contact lenses are used, and It has been suggested that die prevalence of mi­ numerous vitreous floaters have been reported. The pa­ graine is probably markedly underestimated. Estimates tient takes no medication, has no history of illicit drug range from 10% to 34% of the general population, with use, and is otherwise healthy except for a history of mild some authors reporting both age-related and sex-related seasonal allergic rhinitis. There is a family history of differences. Prevalence appears to be highest among migraines. women and among young adults of both sexes. Patients A physical and neurologic examination of the pa­ with acephalgic migraine (migraine aura without head­ tient was performed, and the findings were within nor­ ache) may represent as many as 3% of migraineurs.3 mal limits. The diagnosis o f migraine aura without head­ ache was made. The patient was not placed on ant specific therapeutic intervention. Since his episodes of Case Report scotoma occur only sporadically (every 4 to 6 months) and are not associated with additional symptomology, A 40-ycar-old man presented for evaluation of a 12-year initiation of prophylaxis or abortive therapy was deemed history of periodic visual disturbance. The disturbance, which occurs approximately every 6 months, reportedly inappropriate. begins centrally as a small, bilateral, circular distortion, Long-term follow-up o f the patient includes annual and then expands, over a 20-minute period, into an examination. He has been encouraged to keep a diary of enlarging three-quarter circle of brightly colored and visual phenomena, paying particular attention to activity, flickering lights described as being “similar to multiple diet, and associated symptoms. small prisms laid side-by-side in semicircular fashion.” The disturbance continues to enlarge until it grows out of the patient’s field of vision. There is no history of paresthesia, olfactory or auditory disturbance, nausea, Discussion vomiting, or headache preceding, during, or subsequent The terms acephalgic migraine or m igrain e equivalents have been replaced within the Classification and Diag­ Submitted, revised, December 7, 1990. nostic Criteria for Headache Disorders, Cranial Neural­ gias and Facial Pain by the Headache Classification Com­ From the Department o f Family and Preventive Medicine (DM.P., W M .W ., R .T M .), Department o f Ophthalmology (G.L.W.), and Department o f Neurology! mittee o f the International Headache Society. These Ophthalmology (K.BD .), University o f Utah School o f Medicine, Salt Lake City, Utah. previous designations have been replaced by the term Requests for reprints should be sent to William M. Wilson, PhD, Department o f Family and Preventive Medicine, University o f Utah, 50 N Medical Dr, Salt Lake City, UT migraine aura without headache, which describes migrain­ 84132. ous events exclusively manifested by one of the neuro- © 1991 Appleton & Lange ISSN 0094-3509 520 The fournal of Family Practice, Vol. 32, No. 5,1$ Migraine Pedersen, Wilson, White, et al logical disturbances that usually precede or accompany Table 1. Neurologic Manifestations Associated the headache of classical migraine. with Migraines Approximately 20% o f migraineurs may experience Visual disturbances acephalgic attacks of migraine at one time or another.1 Scintillating scotoma (fortification spectrum/wavy vision) Indeed, that various symptoms can occur in the absence Heminopia Diplopia of any headache has been noted for some time; in fact, Blurred vision visual phenomena were described as early as the 12th cen­ Blindness tury. It is not, therefore, surprising that vivid accounts of Vertigo migraine accompaniments exist throughout history, since Sensor)' disturbance the scintillating scotoma is the most frequently occurring Face (when around the mouth and hand: chiro-oral) visual symptom in migraine with or without headache. Aphasia Terms such as “sparkling, dancing lights,” “vibrating light,” Hemiparesis/Hemiplegia “wiggly line,” “shimmering, like heat off a hot road,” Decreased hearing (very uncommon) “jagged flashes,” and “flickering light” are often used to describe this dramatic occurrence. Colors most often re­ Decreased level of consciousness (rare) ported are red, gold or yellow, green, and blue or purple.4 Pupillary abnormalities While acephalgic migraine would fall into the cate­ Mydriasis gory of migraine aura without headache, episodes of migraine aura without headache can occur in individuals with a history o f classic migraine. W hen acephalgic mi­ estimates that the cortical disturbance responsible for the graine begins after the age of 40, the diagnosis must be scotoma proceeds at a rate of 3 mm per minute through suspect, since throm botic transient ischemia can also be the visual cortex.7 During the scotoma, mental efficiency the cause. These patients have a history of classic mi­ may be impaired, and reasoning, reading, writing, or graine in younger years, then the headaches cease and the speaking may be affected.2'8 Men seem to experience patients begin having what C.M . Fisher has called “late- more specific, sharp, bright lines in their scotoma, while life migraine accompaniments.”s>6 Since one must be women more often describe blurring and bright spots.7 careful to assure no other underlying pathology, exten­ Theories abound regarding the cause of the mi­ sive studies of the heart and vascular system are fre­ graine phenomenon. The major explanations include vas­ quently needed to confirm this diagnosis. cular reactivity (vasoconstriction-vasodilation),8 changes in brain chemistry (serotonin), abnormalities of platelet function, and spreading cortical depression. The vaso­ Pathophysiology spastic and vasodilatory explanation is perhaps the oldest As described above, visual dysfunction is the most fre­ and most persistent and has enjoyed qualitative support quent manifestation o f migraine aura without headache over the years, particularly with regard to the existence of (Table 1). The classic scintillating scotoma, with march vasoconstriction during the migraine process.1 of fortification figures and expansion over time, is char­ In studying patients with classic migraine, Olsen9 acteristic of migraine. Typically, some alteration of per­ and Lauritzen10 found that by intracarotid injection of ception initially occurs either as an indistinct opacity or xenon, regional cerebral blood flow was reduced during the as a loss of illumination. This sensation is followed, in aura, beginning in the occipital area and gradually spread­ seconds to minutes, by the appearance of a small central ing anteriorly over the entire hemisphere. The reduction o f scotoma of only a few degrees that is lined on one side regional cerebral blood flow did not respect vascular terri­ with a luminous, zigzag line, termed the fortification tories, but instead seemed to respect architechtonic territo­ spectrum. The spectral lines usually form an acute angle ries such as the central sulcus and the sylvian fissure.9’10 The and are nonconfluent. These lines may be colored or authors were not able to demonstrate regions o f increased gray, and they appear to oscillate in brightness, suggest- flow; thus, their findings call into question the role of ®g a boiling or rolling effect. The fortification spectrum vasodilation in the migraine process. Furthermore, they expands in the shape o f a horseshoe and is often lined on could not reproduce similar decreases in flow in patients the inner edge by an absent area of vision termed the with common migraine (migraine without aura). negative scotoma.1 The term buildup is used to describe the gradual expansion of the fortification spectrum, and oc- Differential Diagnosis curs m 75% of cases.2 As the scotoma expands, it typi- ca% drifts or “marches” toward the periphery, this pro- As Wiley11 has noted, patients are usually able to ade­ cess generally lasts from 2 0 to 3 0 minutes. There are quately describe their symptoms by using their hands to T|x Journal of Family Practice, Vol. 32, No. 5, 1991 521 Migraine Pedersen, Wilson, White, et 1 show the vibrations starting in the center of the visual Table 2. Causes of Photopsia field and progressing to the periphery over a variable Environmental time course of 15 to 30 minutes. Having the patient Reflections off corrective lenses or windows, lightning flashes and diagram the aura on paper
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