Journal of Neuro-Ophthalmology, March 2007, Volume 27, Issue 1

Most Cases Labeled as Retinal Migraine Are Not Migraine

BACKGROUND: Monocular visual loss has often been labeled "retinal migraine." Yet there is reason to believe that many such cases do not meet the criteria set out by the International Headache Society (IHS), which defines "retinal migraine" as attacks of fully reversible monocular visual disturbance associated with migraine headache and a normal neuro-ophthalmic examination between attacks. METHODS: We performed a literature search of articles mentioning "retinal migraine," "anterior visual pathway migraine," "monocular migraine," "ocular migraine," "retinal vasospasm," "transient monocular visual loss," and "retinal spreading depression" using Medline and older textbooks. We applied the IHS criteria for retinal migraine to all cases so labeled. To be included as definite retinal migraine, patients were required to have had at least two episodes of transient monocular visual loss associated with, or followed by, a headache with migrainous features. RESULTS: Only 16 patients with transient monocular visual loss had clinical manifestations consistent with retinal migraine. Only 5 of these patients met the IHS criteria for definite retinal migraine. No patient with permanent visual loss met the IHS criteria for retinal migraine. CONCLUSIONS: Definite retinal migraine, as defined by the IHS criteria, is an exceedingly rare cause of transient monocular visual loss. There are no convincing reports of permanent monocular visual loss associated with migraine. Most cases of transient monocular visual loss diagnosed as retinal migraine would more properly be diagnosed as "presumed retinal vasospasm."

ORIGINAL CONTRIBUTION Most Cases Labeled as " Retinal Migraine" Are Not Migraine Donna L. Hill, MD, Robert B. Daroff, MD, Anne Ducros, MD, PhD, Nancy J. Newman, MD, and Valerie Biousse, MD Background: Monocular visual loss has often been labeled " retinal migraine." Yet there is reason to believe that many such cases do not meet the crite­ria set out by the International Headache Society ( IHS), which defines " retinal migraine" as attacks of fully reversible monocular visual disturbance asso­ciated with migraine headache and a normal neuro-ophthalmic examination between attacks. Methods: We performed a literature search of articles mentioning " retinal migraine," " anterior visual pathway migraine," " monocular migraine," " ocular migraine," " retinal vasospasm," " transient monocular visual loss," and " retinal spreading depression" using Medline and older textbooks. We applied the IHS criteria for retinal migraine to all cases so labeled. To be included as definite retinal migraine, patients were required to have had at least two episodes of transient monocular visual loss associated with, or followed by, a headache with migrainous features. Results: Only 16 patients with transient monocular visual loss had clinical manifestations consistent with retinal migraine. Only 5 of these patients met the IHS criteria for definite retinal migraine. No patient with permanent visual loss met the IHS criteria for retinal migraine. Conclusions: Definite retinal migraine, as defined by the IHS criteria, is an exceedingly rare cause of transient monocular visual loss. There are no convincing reports of permanent monocular visual loss associated with migraine. Most cases of transient monocular visual loss diagnosed as retinal migraine would more properly be diagnosed as " presumed retinal vasospasm." ( J Neuro- Ophthalmol 2007; 27: 3- 8) After the development of the ophthalmoscope permitted visualization of the retina in vivo, Galezowski ( 1) observed retinal changes suggesting infarction in patients presenting with visual symptoms and presumed migraine headaches. Working with Charcot in Paris, Galezowski had heard Fere ( 2,3), one of Charcot's residents, report that cerebral infarction may be related to migraine. Galezowski ( 4) hypothesized that a permanent " retinal or optic nerve affection," similar to changes described in the brain by Fere, could be secondary to migraine. In 1892, Galezowski ( 4) used the term " ophthalmic megrim" to describe permanent monocular visual loss associated with migraine headache. Subsequently, Fisher ( 5,6) in 1952 and 1971 and Walsh and Hoyt ( 7) in 1969 suggested that the eye itself can be affected by migraine. In 1970, Carroll ( 8) introduced the term " retinal migraine" to describe 15 patients with transient and persis­tent monocular visual loss. None of the patients, however, had associated headaches. Authors have since used the term " retinal migraine" to describe a multitude of mono­cular visual symptoms, including events without associated headache and those resulting in persistent visual loss. Some authors have used other terms, including " anterior visual pathway migraine," " ocular migraine," " ophthalmic migraine," and " monocular migraine" ( 9- 17). In the original ( 1988) classification of headache, the International Headache Society ( IHS) included " retinal migraine" as a subtype of migraine ( 18) and provided strict diagnostic criteria. These criteria stated that retinal migraine could be diagnosed only in the presence of fully reversible monocular visual disturbances associated with Departments of Ophthalmology ( DLH, NJN, VB), Neurology ( NJN, VB), and Neurological Surgery ( NJN), Emory University School of Medicine, Atlanta Georgia; Department of Neurology and Office of the Vice Dean ( RBD), Case Western Reserve University School of Medicine, Cleveland, Ohio; and Acute Headache Center and Department of Neurology ( AD), Hopital Lariboisiere, Paris, France. This study was supported in part by a departmental grant ( Department of Ophthalmology) from Research to Prevent Blindness, Inc, New York, NY, and by core grant P30- EY06360 ( Department of Ophthalmology) from the National Institutes of Health, Bethesda, MD. Dr. Newman is a recipient of a Research to Prevent Blindness Lew R. Wasserman Merit Award. Dr. Hill was supported by unrestricted educational grants from NovaVision and TEVA Neuroscience. Address correspondence to Valerie Biousse, MD, Neuro- ophthalmology Unit, Emory Eye Center, 1365- B Clifton Road, NE, Atlanta, Georgia; E- mail: vbiouss@ emory. edu J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 3 J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 Hill et al typical migraine headache and with a normal neuro-ophthalmic examination between attacks. As with all forms of migraine, other causes had to be excluded. The revised 2004 IHS classification ( 19) also included retinal migraine. As in the 1988 classification, retinal migraine was con­sidered sufficiently atypical as an aura that it was not clas­sified under " migraine with aura" but listed as a separate entity ( Table 1). The diagnostic criteria were unchanged ( Table 2), again requiring " at least two attacks" of " fully reversible" monocular visual symptoms " associated with migraine headache" ( Table 3). Spreading depression ( SD), as described by Leao ( 20) in 1944, is an excitation wave followed by depression of neuronal activity propagating through gray matter with a velocity of approximately 3 mm/ min that investigators have observed in almost all gray matter regions of the central nervous system ( 21). Functional imaging and magneto - encephalographic studies strongly suggest that cortical SD constitutes the biological basis for the occipital aura that precedes headache in migraineurs ( 22,23). SD is often cited as the cause of retinal migraine. TABLE 1. Classification of migraine according to the International Headache Society criteria 1.1 Migrame without aura 1.2 Migraine with aura 1.2.1 Typical aura with migraine headache 1.2.2 Typical aura with non- migraine headache 1.2.3 Typical aura without headache 1.2.4 Familial hemiplegic migraine 1.2.5 Sporadic hemiplegic migraine 1.2.6 Basilar- type migraine 1.3 Childhood periodic syndromes that are commonly precursors of migraine 1.3.1 Cyclical vomiting 1.3.2 Abdominal migraine 1.3.3 Benign paroxysmal vertigo of childhood 1.4 Retinal migraine 1.5 Complications of migraine 1.5.1 Chronic migraine 1.5.2 Status migrainosus 1.5.3 Persistent aura without infarction 1.5.4 Migrainous infarction 1.5.5 Migraine- triggered seizure 1.6 Probable migraine 1.6.1 Probable migraine without aura 1.6.2 Probable migraine with aura 1.6.3 Probable chronic migraine Adapted from The International Classification of Headache Disorders, 2nd edition ( 19). We have reviewed the reported cases attributed to retinal migraine to determine whether they meet the strict criteria set out by the IHS. METHODS Using Medline and textbooks, we searched for arti­cles mentioning " retinal migraine," " anterior visual path­way migraine," " ophthalmic migraine," " ocular migraine," " retinal vasospasm," " transient monocular visual loss," " visual loss and migraine," " visual field defects in mi­graine," and " retinal spreading depression." Applying the most recent IHS criteria ( Table 2) ( 19) for retinal migraine to all reported patients, we separated them into three cate­gories: definite retinal migraine, probable retinal migraine, and possible retinal migraine ( Table 4). Articles were not included in Table 4 if they lacked sufficient informa­tion for adequate classification. We also excluded patients with underlying diseases known to produce migraine- like symptoms, such as cerebral autosomal dominant arterio-pathy with subcortical infarcts and leukoencephalopathy ( CADASIL), antiphospholipid antibody syndrome, or systemic lupus erythematosus ( 24- 27). To be included as definite retinal migraine, the patients must have had at least two episodes of transient monocular visual loss associated with or followed by a migraine headache. RESULTS We discovered 60 articles describing 142 patients with transient or persistent visual symptoms attributed to TABLE 2. International Headache Society criteria for retinal migraine Description: Repeated attacks of monocular visual disturbance, including scintillations, scotomata, or blindness, associated with migrame headache Diagnostic criteria: A. At least two attacks fulfilling criteria B and C B. Fully reversible monocular positive and/ or negative visual phenomena ( scintillations, scotomata, or blindness) confirmed by examination during an attack or ( after proper instruction) by the patient's drawing of a monocular field defect during an attack C. Headache, fulfilling criteria B- D for 1.1 Migraine without aura* begins during the visual symptoms or follows them within 60 minutes D. Normal ophthalmologic examination between attacks E. Not attributed to another disorderf Adapted from The International Classification of Headache Disorders, 2nd edition ( 19). * See Table 3. f Other causes of transient monocular visual loss must be excluded. 4 © 2007 Lippincott Williams & Wilkins Retinal Migraine J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 TABLE 3. International Headache Society criteria for migraine without aura Description: Recurrent headache disorder manifesting in attacks lasting 4- 72 hours. Typical characteristics of the headache are unilateral location, pulsating quality, moderate or severe intensity, aggravation by routine physical activity, Adapted from The International Classification of Headache Disorders, 2nd edition ( 19). Migraine without aura is 1.1 in this classification. * The criteria for headache associated with retinal migraine require " at least two attacks fulfilling criteria B and C" in Table 2. retinal migraine ( 4- 13,24- 57). Among these 142 patients, 39 ( from 25 articles) had persistent visual loss ( 4,6- 8, 11,25,27- 45). Among these 39, there was central retinal artery occlusion in 11 ( 4,6,7,11,25,33,36,42), cilioretinal artery occlusion in 4 ( 38,43), branch retinal artery occlu­sion in 9 ( 31,35,37,39,43), focal retinal ischemia in 1 ( 32), central retinal vein occlusion in 2 ( 27,40), ischemic optic neuropathy in 6 ( 34,41,44), optic atrophy in 5 ( 4,28), and no explanation in 1 ( 6,45). Also among these 39 patients with persistent visual loss, 10 ( 4,6,7,27,31,32,33,34,45) initially presented with recurrent transient monocular visual loss associated with headaches consistent with pre­sumed retinal migraine; these 10 patients developed per­manent visual loss from 6 weeks to 20 years after the onset of transient visual loss. Of the 103 patients with transient visual loss attributed to retinal migraine, only 16 had clinical manifestations that were actually consistent with retinal migraine ( Table 4) ( 45- 53). Among the many articles attributing transient mon­ocular visual loss to retinal migraine ( or equivalent terms for this condition), we found 12 patients with well-documented segmental retinal vasospasm of arteries or veins evident on ophthalmoscopy during an attack of transient monocular visual loss ( 7,13,56- 63). Only 1 of these 12 patients had headache during or immediately after the visual loss ( 57), but the pain did not conform to IHS-defined migraine. Two of the patients had a history of mi­graine without aura ( 56,63), and one had previous episodes of cluster headache ( 13), but no headaches temporally associated with the monocular visual loss. The duration of visual loss varied from seconds to 4 hours, but most episodes lasted a few minutes. All but one patient ( 59) had only negative visual phenomena. DISCUSSION Our review indicates that retinal migraine, as currently denned in the IHS classification, is exceedingly rare. We acknowledge that a literature review can only approximate accuracy, because many reports had incomplete descrip­tions or were published before the 1988 IHS Headache Classification. In addition, not all patients with retinal migraine have been reported. The authors of this article have examined several patients with monocular visual loss who meet the criteria for a diagnosis of retinal migraine. The typical visual aura of migraine occurs in a hemifield rather than a single eye, given that the aura originates from the occipital lobe ( primary visual cortex) ( 64). Many patients report this visual experience as mon­ocular ( 19,65,66), as they may attend only to the visual phe­nomena seen in the temporal field, perhaps because the temporal field is larger than the nasal field. Headache typically follows the aura, although there can be a migrainous aura without headache ( 18,19). Gradually expanding binocular scintillations, scotomas, and zig- zag lines (" scintillating scotoma" or " fortification scotoma"), with a duration usually between 5 and 20 minutes and not more than 60 minutes, are diagnostic of a migrainous visual aura ( 64,65,67), particularly if the aura is followed by headache. In 1971, Richards ( 67) attributed the zig- zag visual phenomena in the aura to the columnar organization of the visual cortex. By contrast, monocular visual phenomena typically originate in the retina, choroid, or optic nerve ( 68). The positive visual phenomena are usually simpler than those that originate in the occipital lobe. They consist of phos-phenes, flashing lights, flickering, or a " rain shower" ( 68- 74). Because these visual manifestations may be caused by any process that impairs ocular or optic nerve blood flow, IHS criteria require that " other causes" be excluded before establishing migraine as the diagnosis ( 18,19,75). The attribution of monocular visual loss to migraine is based on the concept of retinal SD, first described by Gouras ( 76) in 1958 in the frog retina. In 1966, Martins- Ferreira and de Castro ( 77) recorded similar changes in the and association with nausea and/ or photophobia. Diagnostic criteria: A. At least 5 attacks fulfilling criteria B- D* B. Headache attacks lasting 4- 72 hours ( untreated or unsuccessfully treated) C. Headache has at least two of the following characteristics: 1. Unilateral location 2. Pulsating quality 3. Moderate or severe intensity 4. Aggravation by or causing avoidance of routine physical activity ( for example, walking or climbing stairs) D. During headache at least one of the following: 1. Nausea and/ or vomiting 2. Photophobia and phonophobia E. Not attributable to another disorder 5 J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 Hill et al TABLE 4. Previously published patients with transient monocular visual loss suggesting 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Authors ( year) Grosberg et al. ( 2006) Grosberg et al. ( 2006) Gan et al. ( 2005) Guidetti et al. ( 2005) Lewinshtein et al. ( 2004) Lewinshtein et al. ( 2004) Hachinski et al. ( 1973) Corbett ( 1983) Joffe ( 1971) Joffe ( 1971) Joffe ( 1971) Kupersmith et al. ( 1979) Kupersmith et al. ( 1979) Kupersmith et al. ( 1987) Kupersmith et al. ( 1987) Kupersmith et al. ( 1987) Age/ Gender 42/ W 35/ M 40/ M 9/ M 12/ W 13/ M 17/ M 26/ M 18/ M 18/ M 34/ M 53/ W 21/ M 26/ W 16/ W 28/ W Number of episodes Multiple Multiple Multiple Multiple Multiple Multiple Multiple Multiple Multiple Multiple Multiple 2 2 Multiple Multiple Multiple Eye involved OS OS Either OD OD OD Either Either OD Either OS OS OD OD OD OS Type of visual symptoms Positive and negative Negative Negative Negative Positive and negative Positive and negative Positive and negative Negative Negative Negative Negative Negative Negative Negative Negative Negative Duration of visual symptoms 7- 8 minutes 5 minutes 5- 10 minutes 2- 3 minutes < 30 minutes 3 minutes 15 minutes Seconds to minutes NA NA NA 60 minutes 5 minutes 60 minutes NA 20 minutes retinal migraine Headaches Follow visual symptoms Follow visual symptoms Follow visual symptoms During or following visual symptoms. Some without headache Follow visual symptoms No details No details Some with binocular visual aura. Some without headache Some with binocular visual aura No details Some with binocular visual aura Some with binocular visual aura No details No details No details Some with binocular visual aura Side of headache NA Ipsilateral NA Bilateral Ipsilateral NA Ipsilateral NA Ipsilateral Ipsilateral Bilateral Ipsilateral NA Ipsilateral Ipsilateral Bilateral NA, Not available. Only patients with at least two episodes of transient monocular visual loss and headaches suggestive of migraine are included. None of these patients had permanent visual loss. Patients 1- 5 had retinal migraine fulfilling IHS- ICHD2 criteria. We designated these patients as " definite retinal migraine." Patients 6- 7 had headaches that could not be diagnosed definitely as migraine, as defined by IHS- ICHD2. We designated these patients as " probable retinal migraine." Patients 8- 16 are reported in insufficient detail and so are designated " possible retinal migraine." Most had migraine with binocular visual aura, as well as monocular episodes. Patient 6 had a nerve fiber layer infarct during an episode of transient monocular visual loss. optical signal during SD in the chick retina. This model of SD has since been extensively investigated in vitro, mostly on the chick retina ( 78). The technique involves removal of the eye from the animal, followed by separating the retina from the vitreous and placing the eyecup in buffered solution. Mechanical stimulation is applied to the periphery of the retina and a wave, similar to that described by Leao ( 20) propagates in a circular path through the whole tissue. This wave is accompanied by a reversible voltage shift that induces changes in the intrinsic optical properties of the tissue ( 20,23). Variations in light scattering allow the observer to visualize the circling wave as an enlarging dark circle invading the retinal tissue ( Fig. 1) ( 77,78). Retinal SD has only been demonstrated in vitro in avascular chick and frog retina. No in vivo models have demonstrated retinal SD, nor has it been demonstrated in any animal with retinal vasculature. The isolated retina in animal experiments is not representative of the human eye in vivo, which is vascularized and supported by the highly vascular choroid. SD would seem unlikely in the choroid, a blood- filled sponge, or optic nerve, where dysfunction generally produces visual loss and rarely simple 2007 Lippincott Williams & Wilkins Retinal Migraine J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 FIG. 1. Photographic appearance of light- scattering changes produced by retinal spreading depression in a chick eyecup immersed in bathing solution at different time intervals after mechanical stimulation at the center of the delineated circle. A. Before stimulation. B. 40 seconds after stimulation. C. 100 seconds after stimulation. ( Adapted from: Martins- Ferreira and Nedergaard ( 78) with permission from Elsevier.) phosphenes. Although some of the monocular visual symptoms reported as retinal migraine progress and propagate at the same speed as cortical SD, retinal SD has never been demonstrated in mammals. Scientists studying retinal SD have never suggested any clinical correlation with migraine in humans. Retinal vasospasm can produce transient monocular visual loss. However, in the vast majority of well- documented cases of retinal vasospasm, the clinical presentation is not suggestive of migraine. Only 1 of the 12 well- documented patients with ophthalmoscopically seen vasospasm un­covered in our search had headache during or immediately after the visual loss ( 57), and the pain did not conform to IHS- defined migraine. All but one of these patients ( 59) had only negative visual phenomena. Based on our review, we find no basis for considering migraine to be the cause of permanent monocular visual loss unless the patient had previous transient monocular visual episodes consistent with IHS- defined retinal migraine. Two recent reviews suggesting that permanent monocular visual loss is present in up to 50% of patients with retinal migraine included patients who did not have IHS- defined retinal migraine before the visual loss ( 45,79). The various retinal lesions reported in presumed retinal migraine include central retinal artery occlusion, branch retinal artery occlu­sion, localized retinal ischemia, central retinal vein occlu­sion, and optic atrophy. These conditions cannot reasonably be explained by a single unifying mechanism such as SD. What authors have referred to as " retinal migraine" prob­ably represents a large heterogeneous group of underlying disorders involving the retina, choroid, or optic nerve. Based on our review, retinal migraine is unlikely to be the cause of transient or persistent monocular visual loss. Most reported cases attributed to this condition have not met strict IHS criteria. Moreover, there are no studies in humans to suggest that the retina is subject to SD, the process believed to underlie the binocular visual aura emanating from the visual cortex in migraine. We suggest that most patients reported to have had retinal migraine as the cause of transient monocular visual loss would be better labeled as having had " presumed retinal vasospasm ( 80)." REFERENCES 1. Amalric PM. The Galezowski tradition in Paris. Doc Ophthalmol 1999; 98: 105- 13. 2. Fere C. Contribution a 1' etude de la migraine ophthalmique. Rev Med ( Paris) 1881; 1: 625^ 9. 3. Fere C. Note sur un cas de migraine ophthalmique a acces repetes et suivie de mort. Rev Med ( Paris) 1883; 3: 194- 201. 4. Galezowski X. Ophthalmic megrim: an affection of the vasomotor nerves of the retina and retinal centre which may end in a thrombosis. Lancet 1882; 1: 176- 9. 5. Fisher CM. Transient monocular blindness associated with hemi­plegia. AMA Arch Ophthalmol 1952; 47: 167- 203. 6. Fisher CM. Cerebral ischemia- less familiar types. Clin Neurosurg 1971; 18: 267- 336. 7. Walsh FB, Hoyt WF Vascular lesions and circulatory disorders of the nervous system. In: Walsh FB, Hoyt WF, eds. Clinical Neuro-ophthalmology, 3rded. Baltimore: Williams & Wilkins; 1969: 1671- 89. 8. Carroll D. Retinal migraine. Headache 1970; 10: 9- 13. 9. Doyle E, Vote BJ, Casswell AG. Retinal migraine: caught in the act. Br J Ophthalmol 2004; 88: 301- 2. 10. Bigal M, Welsh KM. Basilar migraines and retinal migraines. In: Olesen J, Goadsby PJ, Ramadan NM, et al., eds. The Headaches, 3rd ed. Philadelphia: Lippincott Williams & Wilkins; 2006: 589- 93. 11. Pandit JC, Fritsche P. Permanent monocular blindness and ocular migraine. JR Soc Med 1997; 90: 691- 2. 12. Wolter JR, Burchfield WJ. Ocular migraine in a young man resulting in unilateral transient blindness and retinal edema. J Pediatr Opthalmol 1971; 8: 173- 6. 13. Kline LB, Kelly CL. Ocular migraine in a patient with cluster headaches. Headache 1980; 20: 253- 7. 14. Goodwin JA, Gorelick PB, Helgason CM. Symptoms of amaurosis fugax in atherosclerotic carotid artery disease. Neurology 1987; 37: 829- 33. 15. Hupp SL, Kline LB, Corbett JJ. Complicated migraine and vision. Headache Q 1990; 1: 146- 51. 16. Daroff RB. The eye and headache. Neuro Ophthalmol Jpn 2002; 19: 112- 24. 17. Daroff RB. Ocular and non- ocular causes of eye and/ or head pain, and the ophthalmic manifestations of headaches. Headache Pain 2003; 14: 87- 92. 18. Headache Classification Committee of the International Headache Society. Classification and diagnostic criteria for headache disorders, cranial neuralgias, and facial pain. Cephalalgia 1988; 8( Suppl 7): 1- 96. 19. Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders, 2nd edition. Cephalalgia 2004; 24( Suppl 1): 1- 160. 7 J Neuro- Ophthalmol, Vol. 27, No. 1, 2007 Hill et al 20. Leao AAP. Spreading depression of activity in the cerebral cortex. J Neurophysiol 1944; 7: 359- 90. 21. Somjen GG. Mechanisms of spreading depression and hypoxic spread­ing depression- like depolarization. Physiol Rev 2001; 81: 1065- 96. 22. Teive HA, Kowacs PA, Maranhao Filho P, et al. Leao's cortical spreading depression: from experimental " artifact" to physiological principle. Neurology 2005; 65: 1455- 9. 23. Bolay H, Moskowitz MA. The emerging importance of cortical spreading depression in migraine headache. Rev Neurol ( Paris) 2005; 161: 655- 7. 24. Ravaglia S, Costa A, Santorelli F, et al. Retinal migraine as unusual feature of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( CADASIL). Cephalalgia 2004; 24: 74- 7. 25. Gutrecht JA, Kattwinkel N, Stillman MJ. Retinal migraine, chorea, and retinal artery thrombosis in a patient with primary antiphos-pholipid antibody syndrome. J Neurol 1991; 238: 55- 6. 26. Donders RC, Kappelle LJ, Derksen RH, et al. Transient monocular blindness and antiphospholipid antibodies in systemic lupus erythematosus. Neurology 1998; 51: 535^ 0. 27. Coppeto JR, Lessell S, Sciarra R, et al. Vascular retinopathy in migraine. Neurology 1986; 36: 267- 70. 28. Connor RC. Complicated migraine: a study of permanent neurolog­ical and visual defects caused by migraine. Lancet 1962; 2: 1072- 5. 29. Dunning HS. Intracranial and extracranial vascular accidents in migraine. Arch Neurol Psychiatry 1942; 48: 396^ 0. 30. Fujino T, Akiya S, Takagi S, et al. Amaurosis fugax for a long duration. J Clin Neuroophthalmol 1983; 3: 9- 12. 31. Inan LE, Uysal H, Ergun U, et al. Complicated retinal migraine. Headache 1994; 34: 50- 2. 32. James CB, Buckley SA, Cock S, et al. Retinal migraine. Lancet 1993; 342: 690. 33. Katz B. Migrainous central retinal artery occlusion. J Clin Neuro­ophthalmol 1986; 6: 69- 71. 34. Lee AG, Brazis PW, Miller NR. Posterior ischemic optic neuropathy associated with migraine. Headache 1996; 36: 506- 9. 35. Poole CJ, Ross Russell RW, Harrison P, et al. Amaurosis fugax under the age of 40 years. J Neurol Neurosurg Psychiatry 1987; 50: 81^ k 36. Silberberg DH, Laties AM. Occlusive migraine. Trans Pa Acad Ophthalmol Otolaryngol 1974; 27: 34- 8. 37. Glenn AM, Shaw PJ, Howe JW, et al. Complicated migraine resulting in blindness due to bilateral retinal infarction. Br J Ophthalmol 1992; 76: 189- 90. 38. Hykin PG, Gartry D, Brazier DJ, et al. Bilateral cilio- retinal artery occlusion in classic migraine. Postgrad Med J 1991; 67: 282^ k 39. Beversdorf D, Stommel E, Allen C, et al. Recurrent branch retinal infarcts in association with migraine. Headache 1997; 37: 396- 9. 40. Friedman MW. Occlusion of central retinal vein in migraine. AMA Arch Ophthalmol 1951; 45: 678- 82. 41. Weinstein JM, Feman SS. Ischemic optic neuropathy in migraine. Arch Ophthalmol 1982; 100: 1097- 100. 42. Gray JA, Carroll JD. Retinal artery occlusion in migraine. Postgrad Med J 1985; 61: 517- 8. 43. Brown GC, Magargal LE, Shields JA, et al. Retinal arterial obstruc­tion in children and young adults. Ophthalmology 1981; 88: 18- 25. 44. O'Hara M, O'Connor PS. Migrainous optic neuropathy. J Clin Neuroophthalmol 1984; 4: 85- 90. 45. Grosberg BM, Solomon S, Friedman DI, et al. Retinal migraine reappraised. Cephalalgia 2006; 26: 1275- 86. 46. Gan KD, Mouradian MS, Weis E, et al. Transient monocular visual loss and retinal migraine. CMAJ2005; 173: 1441- 2. 47. Lewinshtein D, Shevell MI, Rothner AD. Familial retinal migraines. Pediatr Neurol 2004; 30: 356- 7. 48. Corbett JJ. Neuro- ophthalmic complications of migraine and cluster headaches. Neurol Clin 1983; 1: 973- 95. 49. Hachinski VC, Porchawka J, Steele JC. Visual symptoms in the migraine syndrome. Neurology 1973; 23: 570- 9. 50. Joffe SN. Retinal blood vessel diameter during migraine. SAfr Med J 1971; 45: 1215- 8. 51. Guidetti V, Tagliente F, Galli F An adolescent with headache. In: Purdy R, Rapoport A, Sheftell F, et al, eds. Advanced Therapy of Headache, 2nd ed. London: BC Decker, 2005: 27- 9. 52. Kupersmith MJ, Hass WK, Chase NE. Isoproterenol treatment of visual symptoms in migraine. Stroke 1979; 10: 299- 305. 53. Kupersmith MJ, Warren FA, Hass WK. The non- benign aspects of migraine. Neuroophthalmology 1987; 7: 1- 10. 54. Tomsak RL, Jergens PB. Benign recurrent transient monocular blindness: a possible variant of acephalgic migraine. Headache 1987; 27: 66- 9. 55. Grosberg BM, Solomon S. Retinal migraine: two cases of prolonged but reversible monocular visual defects. Cephalalgia 2006; 26: 754- 7. 56. Appleton R, Farrell K, Buncic JR, et al. Amaurosis fugax in teen­agers. A migraine variant. Am JDis Child 1988; 142: 331- 3. 57. Killer HE, Forrer A, Flammer J. Retinal vasospasm during an attack of migraine. Retina 2003; 23: 253^ k 58. Humphrey WT. Central retinal artery spasm. Ann Ophthalmol 1979; 11: 877- 81. 59. Bernard GA, Bennett JL. Vasospastic amaurosis fugax. Arch Ophthalmol 1999; 117: 1568- 9. 60. Petzold A, Islam N, Plant GT Video reconstruction of vasospastic transient monocular blindness. N Engl J Med 2003; 348: 1609- 10. 61. Winterkorn JM, Kupersmith MJ, Wirtschafter JD, et al. Treatment of vasospastic amaurosis fugax with calcium- channel blockers. N Engl J Med 1993; 329: 396- 8. 62. Winterkorn JM, Teman AJ. Recurrent attacks of amaurosis fugax treated with calcium channel blocker. Ann Neurol 1991; 30: 423- 5. 63. Burger SK, Saul RF, Selhorts JB, et al. Transient monocular blindness caused by vasospasm. N Engl J Med 1991; 325: 870- 3. 64. Russell MB, Olesen J. A nosographic analysis of the migraine aura in a general population. Brain 1996; 119: 355- 61. 65. Rasmussen BK. Epidemiology of migraine. In: Olesen J, Goadsby PJ, Ramadan NM, et al, eds. The Headaches, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2006: 235^ 2. 66. Eriksen MK, Thomsen LL, Olesen J. The visual aura rating scale ( VARS) for migraine aura diagnosis. Cephalalgia 2005; 25: 801- 10. 67. Richards W The fortification illusions of migraines. Sci Am 1971; 224: 88- 96. 68. Biousse V, Trobe JD. Transient monocular visual loss. Am J Ophthalmol 2005; 140: 717- 21. 69. Evans RW, Daroff RB. Monocular visual aura with headache: retinal migraine? Headache 2000; 40: 603^ k 70. Hupp SL, Kline LB, Corbett JJ. Visual disturbances of migraine. Surv Ophthalmol 1989; 33: 221- 36. 71. Troost BT, Tomsak RL. Ophthalmoplegic migraine and retinal migraine. In: Olesen J, Tfelt- Hansen P, Welch KM, eds. The Headaches, 1st ed. New York: Raven Press, 1993: 421- 6. 72. Biousse V, Touboul PJ, D'Angelejan- Chatillon J, et al. Ophthalmo­logic manifestations of internal carotid artery dissection. Am J Ophthalmol 1998; 126: 565- 77. 73. Olesen J, Friberg L, Olsen TS, et al. Ischaemia- induced ( symptom­atic) migraine attacks may be more frequent than migraine- induced ischaemic insults. Brain 1993; 116: 187- 202. 74. Ramadan NM, Tietjen GE, Levine SR, et al. Scintillating scotomata associated with internal carotid artery dissection: report of three cases. Neurology 1991; 41: 1084- 7. 75. Bousser MG, Welch KM. Relation between migraine and stroke. Lancet Neurol 2005; 4: 533^ 2. 76. Gouras P. Spreading depression of activity in amphibian retina. Am J Physiol 1958; 195: 28- 32. 77. Martins- Ferreira H, de Castro GO. Light scattering changes accompanying spreading depression in isolated retina. J Neuro­physiol 1966; 29: 715- 26. 78. Martins- Ferreira H, Nedergaard M, Nicholson C. Perspectives on spreading depression. Brain Res Brain Res Rev 2000; 32: 215- 34. 79. Grosberg BM, Solomon S, Lipton RB. Retinal migraine. Curr Pain Headache Rep 2005; 9: 268- 71. 80. Winterkorn JMS, Burde RM. Vasospasm- not migraine- in the anterior visual pathway. Ophthalmol Clin NA 1996; 9: 393^ 05. 8 © 2007 Lippincott Williams & Wilkins