Visual Evoked Cortical Potentials for Single Flashes and Flickering Light in Migraine

Lehtonen, Janne

doi:10.1111/j.1526-4610.1974.hed1401001.x

Cited by 64 publications

(38 citation statements)

References 17 publications

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“…Correlations with migraine duration have been looked for in SFVEPs, RFVEPs, and PRVEPs,24 29 30 but the range of duration in all these studies was fairly small, and in some29 30 the number of subjects with MA was also small. Doubtless the relation has only been recognised in the present study because of the large number of subjects with MA and their wide range of duration of migraine.…”

Section: Discussionmentioning

confidence: 99%

Long term decline of P100 amplitude in migraine with aura

Khalil

Legg²,

Anderson³

2000

Journal of Neurology, Neurosurgery &Amp; Psychiatry

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Objectives-To investigate visual function in migraine using visual evoked potentials. Methods-Electroretinograms(ERGs) and visual evoked potentials (VEPs) to single flash (SF) and pattern reversal (PR) stimuli were studied in 92 migraine subjects and 62 controls. Results-In subjects with migraine, ERGs to single flash were normal. Mean latencies of the P1 and P2 waves in the SFVEP were increased at the occiput by 6% and 4% respectively, but normal at the vertex. Mean latency of the P100 wave in the PRVEP was increased by 5%. These increases were not related to the presence or absence of an aura or to the duration of migraine. P100 amplitude showed a more complex abnormality. It was increased in migraine without aura by 23% compared with controls, regardless of duration of migraine. In migraine with aura it was similarly increased, by 23%, in cases of short duration, but in addition it showed a sharp decline with duration. In cases with a duration of 30 or more years it was 36% less than in cases of short duration, and 21% less than in controls. Conclusions-Subjects with migraine have constitutionally prolonged VEP latencies and increased P100 amplitude, but the latter declines to below normal in cases with a long history of migraine with aura. This decline may reflect subtle neuronal damage within the visual system from repeated transient ischaemia experienced during the aura. Future electrophysiological and other studies will need to be controlled for duration of migraine history. The studies reported here formed part of a PhD project 4 in which visual function was studied in 92 subjects with migraine and 62 controls, by neurophysiological and psychophysical methods. Here we report the results of investigation by electroretinogram (ERG), SFVEP, and PRVEP. Some preliminary data have already been published. Methods SUBJECTSThe patients in this study were not a random sample of the migraine population. They came from a wide age range, and there was a deliberate selection for those with a visual aura and with attacks precipitated by visual stimuli, to provide subgroups large enough for meaningful comparisons. Controls were found among colleagues, the spouses, or friends of subjects with migraine, and other volunteers. All subjects had a visual acuity of 6/6 or better, and none of them had any visual disorder.All 92 subjects fulfilled the International Headache Society (IHS) criteria for a diagnosis of migraine with or without aura.7 There were 72 women and 20 men, aged 16-59 years (mean 40.2 (SD 12.5) years). All were free of headache at the time of testing, and none were taking prophylactic treatment. Forty seven had migraine with aura (MA), 37 had migraine without aura (MO), and eight had both. Results from these eight patients have been included only when the whole migraine group is considered. All patients with MA had a visual aura, and seven also had other aura symptoms. Seventy three patients reported attacks triggered by visual stimuli, such as bright lights, flashing lights, or patterns. Migraine ...

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Section: Discussionmentioning

confidence: 99%

Long term decline of P100 amplitude in migraine with aura

Khalil

Legg²,

Anderson³

2000

Journal of Neurology, Neurosurgery &Amp; Psychiatry

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“…In early studies it was preferred to use single flashes to evoke visual potentials (flash-evoked visual potentials). In almost all these pilot studies, the main evoked potential (EP) components showed higher amplitudes in migraineurs than in controls [8][9][10] except one [11]. Early visual evoked potential (VEP) components were reduced on the side opposite to the aura [12].…”

Section: Visual Cortex Response Patterns In Migrainementioning

confidence: 99%

Electrophysiological response patterns of primary sensory cortices in migraine

Ambrosini

Schoenen

2006

J Headache Pain

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Migraine is an ictal disorder characterised by a particular vulnerability of patients to sensory overload, both during and outside of the attack. Central nervous system dysfunctions are supposed to play a pivotal role in migraine. Electroneurophysiological methods, which aim to investigate sensory processing, seem thus particularly appropriate to study the pathophysiology of migraine. We have thus reviewed evoked potential studies performed in migraine patients. Although results are in part contradictory, these studies nonetheless demonstrate an interictal dysfunction of sensory cortices, and possibly of subcortical structures, in migraine with and without aura. The predominant abnormality is a deficient habituation of evoked responses to repeated stimuli, probably due to cortical, and possibly widespread neural, "dysexcitability".

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“…A generalized cortical inter-ictal hyper-excitability, more pronounced in the visual cortex, has been suggested in migraine [1, 2], although other psychophysical tests of the visual system yielded results suggestive of occipital cortex hypo-excitability or lack of intra-cortical excitation [3]. Neurophysiologic evidence for inter-ictal primary visual cortex hyper-excitability is nevertheless controversial, with some studies demonstrating amplitude differences of visual evoked responses in patients with migraine compared with controls [4–6], and other studies not confirming such results [7, 8]. However, a recent study using VEP with paired pulse stimulation in patients affected by migraine without aura demonstrated a reduced inhibitory response to the second pulse, compatible with a condition of reduced inhibition-increased excitability [9].…”

Section: Introductionmentioning

confidence: 99%

Transcranial magnetic stimulation of visual cortex in migraine patients: a systematic review with meta-analysis

et al. 2012

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We systematically reviewed the literature to evaluate the prevalence of phosphenes and the phosphene threshold (PT) values obtained during single-pulse transcranial magnetic stimulation (TMS) in adults with migraine. Controlled studies measuring PT by single-pulse TMS in adults with migraine with or without aura (MA, MwA) were systematically searched. Prevalence of phosphenes and PT values were assessed calculating mean difference (MD) and odds ratio (OR) with 95 % confidence intervals (CI). Ten trials (277 migraine patients and 193 controls) were included. Patients with MA had statistically significant lower PT compared with controls when a circular coil was used (MD −28.33; 95 % CI −36.09 to −20.58); a similar result was found in MwA patients (MD −17.12; 95 % CI −23.81 to −10.43); using a figure-of-eight coil the difference was not statistically significant. There was a significantly higher phosphene prevalence in MA patients compared with control subjects (OR 4.21; 95 % CI 1.18–15.01). No significant differences were found either in phosphene reporting between patients with MwA and controls, or in PT values obtained with a figure-of-eight coil in MA and MwA patients versus controls. Overall considered, these results support the hypothesis of a primary visual cortex hyper-excitability in MA, providing not enough evidence for MwA. A significant statistical heterogeneity reflects clinical and methodological differences across studies, and higher temporal variabilities among PT measurements over time, related to unstable excitability levels. Patients should therefore be evaluated in the true interictal period with an adequate headache-free interval. Furthermore, skull thickness and ovarian cycle should be assessed as possible confounding variables, and sham stimulation should be performed to reduce the rate of false positives. Phosphene prevalence alone cannot be considered a measure of cortical excitability, but should be integrated with PT evaluation.

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Visual Evoked Cortical Potentials for Single Flashes and Flickering Light in Migraine

Cited by 64 publications

References 17 publications

Long term decline of P100 amplitude in migraine with aura

Long term decline of P100 amplitude in migraine with aura

Electrophysiological response patterns of primary sensory cortices in migraine

Transcranial magnetic stimulation of visual cortex in migraine patients: a systematic review with meta-analysis

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