Migraine aura and related phenomena: beyond scotomata and scintillations

Reduced functional connectivity between salience and visual networks in migraine with aura

BACKGROUND

Migraine with visual aura (MA) is associated with distinct visual disturbances preceding migraine attacks, but shares other visual deficits in between attacks with migraine without aura (MO). Here, we seek to determine if abnormalities specific to interictal MA patients exist in functional brain connectivity of intrinsic cognitive networks. In particular, these networks are involved in top-down modulation of visual processing.

METHODS

Using resting-state functional magnetic resonance imaging, whole-brain functional connectivity maps were derived from seeds placed in the anterior insula and the middle frontal gyrus, key nodes of the salience and dorsal attention networks, respectively. Twenty-six interictal MA patients were compared with 26 matched MO patients and 26 healthy matched controls.

RESULTS

The major findings were: connectivity between the anterior insula and occipital areas, including area V3A, was reduced in MA but not in MO. Connectivity changes between the anterior insula and occipital areas further correlated with the headache severity in MA only.

CONCLUSIONS

The unique pattern of connectivity changes found in interictal MA patients involved area V3A, an area previously implicated in aura generation. Hypoconnectivity to this and other occipital regions may either represent a compensatory response to occipital dysfunctions or predispose MA patients to the development of aura.

Redefining amaurosis fugax

Amaurosis fugax is a common term fraught with different interpretations. Disparities inunderstanding appear to be related to professional training. A new framework to facilitateinterdisciplinary communication and clinical research is presented.

Vision and migraine

BACKGROUND

Migraine, a common brain disorder, disrupts vision more than any other motor or sensory function. The possible visual aura symptoms vary from occasional small flashes of light to complex visual hallucinations, the stereotyped teichopsia being the most typical pattern. It is unclear as to why aura occurs serendipitously, sometimes preceding, but also occurring after the headache, and why aura can present with multiple phenotypes.

METHODS

To better understand the nature of visual disturbances in migraine, 4 aspects must be considered: What are the visual perceptions in migraine; why vision is affected in migraine; the role of cortical spreading depression (CSD); how does vision could affect migraine. Evidence supporting each of these topics is reviewed.

RESULTS

CSD travels at a similar pace as the march of symptoms in the visual field. Functional neuroimaging studies show spreading changes compatible with CSD regardless of aura. Computerized models reproducing the CSD march on the visual cortex predict a sensory experience compatible with naturally occurring visual auras. Rather than spreading in all directions, these models suggest that CSD moves preferentially in one direction. Migraine-preventive drugs increase the CSD threshold and reduce CSD velocity. Blind migraineurs may present atypical visual aura, with more colors, shorter duration, different shapes, and atypical symptoms, such as auditory experiences.

CONCLUSIONS

CSD is the underlying phenomenon in migraine with and without aura. In migraine without aura, CSD probably does not run over silent areas of the cortex, but rather does not reach symptomatology threshold. Normal vision is important in migraine, as lack of sight may change the visual experience during migraine aura, probably due to cortical reorganization and changes in local susceptibility to CSD.

Cortical hot spots and labyrinths: why cortical neuromodulation for episodic migraine with aura should be personalized

Stimulation protocols for medical devices should be rationally designed. For episodic migraine with aura we outline model-based design strategies toward preventive and acute therapies using stereotactic cortical neuromodulation. To this end, we regard a localized spreading depression (SD) wave segment as a central element in migraine pathophysiology. To describe nucleation and propagation features of the SD wave segment, we define the new concepts of cortical hot spots and labyrinths, respectively. In particular, we firstly focus exclusively on curvature-induced dynamical properties by studying a generic reaction-diffusion model of SD on the folded cortical surface. This surface is described with increasing level of details, including finally personalized simulations using patient's magnetic resonance imaging (MRI) scanner readings. At this stage, the only relevant factor that can modulate nucleation and propagation paths is the Gaussian curvature, which has the advantage of being rather readily accessible by MRI. We conclude with discussing further anatomical factors, such as areal, laminar, and cellular heterogeneity, that in addition to and in relation to Gaussian curvature determine the generalized concept of cortical hot spots and labyrinths as target structures for neuromodulation. Our numerical simulations suggest that these target structures are like fingerprints, they are individual features of each migraine sufferer. The goal in the future will be to provide individualized neural tissue simulations. These simulations should predict the clinical data and therefore can also serve as a test bed for exploring stereotactic cortical neuromodulation.

The visual system in migraine: from the bench side to the office

BACKGROUND

Throughout history, migraine-associated visual symptoms have puzzled patients, doctors, and neuroscientists. The visual aspects of migraine extend far beyond the aura phenomena, and have several clinical implications.

METHODS

A narrative review was conducted, beginning with migraine mechanisms, then followed by pertinent aspects of the anatomy of visual pathways, clinical features, implications of the visual system on therapy, migraine on visually impaired populations, treatment of visual auras and ocular (retinal) migraine, effect of prophylactic migraine treatments on visual aura, visual symptoms induced by anti-migraine or anti-headache drugs, and differential diagnosis.

RESULTS

A comprehensive narrative review from both basic and clinical standpoints on the visual aspects of migraine was attained; however, the results were biased to provide any useful information for the clinician.

CONCLUSION

This paper achieved its goals of addressing and condensing information on the pathophysiology of the visual aspects of migraine and its clinical aspects, especially with regards to therapy, making it useful not only for those unfamiliar to the theme but to experienced physicians as well.

Features of migraine aura in teenagers

BACKGROUND

Complex migraine aura in teenagers can be complicated to diagnose. The aim of this study was to present detailed features of migraine aura in teenage migraineurs.

METHODS

This cross-sectional study was conducted in the period from 2008 till 2013. A total number of 40 teenage migraineurs (20 females and 20 males) met criteria for this study. The patients were interviewed using a specially designed questionnaire for collecting data about migraine aura features. Main outcome measures were frequency of visual, somatosensory and higher cortical dysfunction (HCD) symptoms in teenage migraineurs population during the aura, and also within each individual.

RESULTS

Visual aura was reported in every attack, followed by somatosensory (60%) and dysphasic (36.4%) aura. Scintillating scotoma and blurry vision were mostly reported and predominant visual symptoms. The most common somatosensory symptom was numbness in hand. HCD were reported by 22 (55%) patients. Slowed speech was mostly reported symptom of HCD, followed by dyslexia, déjà vu phenomenon, color dysgnosia, and dyspraxia. In patients with HCD, aura frequency per year (6.18 ± 3.17 vs. 3.33 ± 2.03, p = 0.003) and prevalence of somatosensory symptoms (77.3% vs. 38.9%, p = 0.014) were significantly higher than in patients without HCD.

CONCLUSIONS

Aura symptoms vary to a great extent in complexity in teenage migraineurs. Consequently, results obtained in this study provide useful information for clinicians when faced with unusual migraine aura.

Late-life migraine accompaniments: A narrative review

BACKGROUND

Migraine is one of the most common chronic neurological disorders. In 1980, C. Miller Fisher described late-life migraine accompaniments as transient neurological episodes in older individuals that mimic transient ischemic attacks. There has not been an update on the underlying nature and etiology of late-life migraine accompanimentsd since the original description.

PURPOSE

The purpose of this article is to provide a comprehensive and extensive review of the late-life migraine accompaniments including the epidemiology, clinical characteristics, differential diagnosis, and treatment.

METHODS

Literature searches were performed in MEDLINE®, PubMed, Cochrane Library, and EMBASE databases for publications from 1941 to July 2014. The search terms "Migraine accompaniments," "Late life migraine," "Migraine with aura," "Typical aura without headache," "Migraine equivalents," "Acephalic migraine," "Elderly migraine," and "Transient neurological episodes" were used.

CONCLUSION

Late-life onset of migraine with aura is not rare in clinical practice and can occur without headache, especially in elderly individuals. Visual symptoms are the most common presentation, followed respectively by sensory, aphasic, and motor symptoms. Gradual evolution, the march of transient neurological deficits over several minutes and serial progression from one symptom to another in succession are typical clinical features for late-life migraine accompaniments. Transient neurological disturbances in migraine aura can mimic other serious conditions and can be easily misdiagnosed. Careful clinical correlation and appropriate investigations are essential to exclude secondary causes. Treatments are limited and still inconsistent.

Pathophysiology and treatment of alien hand syndrome

Background

Alien hand syndrome (AHS) is a disorder of involuntary, yet purposeful, hand movements that may be accompanied by agnosia, aphasia, weakness, or sensory loss. We herein review the most reported cases, current understanding of the pathophysiology, and treatments.

Methods

We performed a PubMed search in July of 2014 using the phrases “alien hand syndrome,” “alien hand syndrome pathophysiology,” “alien hand syndrome treatment,” and “anarchic hand syndrome.” The search yielded 141 papers (reviews, case reports, case series, and clinical studies), of which we reviewed 109. Non-English reports without English abstracts were excluded.

Results

Accumulating evidence indicates that there are three AHS variants: frontal, callosal, and posterior. Patients may demonstrate symptoms of multiple types; there is a lack of correlation between phenomenology and neuroimaging findings. Most pathologic and functional imaging studies suggest network disruption causing loss of inhibition as the likely cause. Successful interventions include botulinum toxin injections, clonazepam, visuospatial coaching techniques, distracting the affected hand, and cognitive behavioral therapy.

Discussion

The available literature suggests that overlap between AHS subtypes is common. The evidence for effective treatments remains anecdotal, and, given the rarity of AHS, the possibility of performing randomized, placebo-controlled trials seems unlikely. As with many other interventions for movement disorders, identifying the specific functional impairments caused by AHS may provide the best guidance towards individualized supportive care.

Cortical spreading depression: origins and paths as inferred from the sequence of events during migraine aura

Patients with migraine with aura often experience a variety of visual and somatosensory phenomena and disturbances of higher cortical functions. Analysis of these alterations may provide important information about the involvement of different cortical regions in cortical spreading depression (CSD). We report five cases of migraineurs who experience unusually abundant clinical phenomena during auras. These patients were selected from a cohort of migraine with aura patients who were interviewed, using a specially designed questionnaire, to evaluate the presence of higher cortical dysfunctions. On the basis of the aura symptoms they reported, we attempted to infer the origin and the possible paths of CSD in each patient. According to their reported symptoms, CSD could begin in the primary visual cortex, in the primary somatosensory cortex or simultaneously in both, and propagate to the posterior parietal cortex, the temporal lobe and Broca's area. We believe that clinical descriptions of aura could play an important role in further investigations of the pathophysiology of migraine.

Migraineurs without aura show microstructural abnormalities in the cerebellum and frontal lobe

The involvement of the cerebellum in migraine pathophysiology is not well understood. We used a biparametric approach at high-field MRI (3 T) to assess the structural integrity of the cerebellum in 15 migraineurs with aura (MWA), 23 migraineurs without aura (MWoA), and 20 healthy controls (HC). High-resolution T1 relaxation maps were acquired together with magnetization transfer images in order to probe microstructural and myelin integrity. Clusterwise analysis was performed on T1 and magnetization transfer ratio (MTR) maps of the cerebellum of MWA, MWoA, and HC using an ANOVA and a non-parametric clusterwise permutation F test, with age and gender as covariates and correction for familywise error rate. In addition, mean MTR and T1 in frontal regions known to be highly connected to the cerebellum were computed. Clusterwise comparison among groups showed a cluster of lower MTR in the right Crus I of MWoA patients vs. HC and MWA subjects (p = 0.04). Univariate and bivariate analysis on T1 and MTR contrasts showed that MWoA patients had longer T1 and lower MTR in the right and left pars orbitalis compared to MWA (p < 0.01 and 0.05, respectively), but no differences were found with HC. Lower MTR and longer T1 point at a loss of macromolecules and/or micro-edema in Crus I and pars orbitalis in MWoA patients vs. HC and vs. MWA. The pathophysiological implications of these findings are discussed in light of recent literature.

Face recognition in patients with migraine

OBJECTIVES

Prosopagnosia is a rare dysfunction seen during the aura phase of migraine. We aimed to evaluate the face recognition, which has not previously been investigated in migraineurs during the interictal period, and its relationships with clinical features.

METHODS

Seventy-four migraineurs, with or without aura, diagnosed according to the International Headache Society criteria and 37 healthy control subjects were included. Benton face recognition test (BFRT) and judgment of line orientation test (LOT) for complex visual perception were applied to all participants.

RESULTS

Migraineurs showed significantly lower performance in both of the BFRT and LOT scores (P = 0.027; P = 0.014, respectively), indicating impaired visuospatial perception. In the subgroup analysis, these impairments were more pronounced in the group with migraine without aura.

CONCLUSION

Migraineurs had poorer performance in both face recognition and visuospatial perception. These findings could be based on functional differences in the migraineurs' brain or genetic changes.

Migraine generator network and spreading depression dynamics as neuromodulation targets in episodic migraine

Migraine is a common disabling headache disorder characterized by recurrent episodes sometimes preceded or accompanied by focal neurological symptoms called aura. The relation between two subtypes, migraine without aura (MWoA) and migraine with aura (MWA), is explored with the aim to identify targets for neuromodulation techniques. To this end, a dynamically regulated control system is schematically reduced to a network of the trigeminal nerve, which innervates the cranial circulation, an associated descending modulatory network of brainstem nuclei, and parasympathetic vasomotor efferents. This extends the idea of a migraine generator region in the brainstem to a larger network and is still simple and explicit enough to open up possibilities for mathematical modeling in the future. In this study, it is suggested that the migraine generator network (MGN) is driven and may therefore respond differently to different spatio-temporal noxious input in the migraine subtypes MWA and MWoA. The noxious input is caused by a cortical perturbation of homeostasis, known as spreading depression (SD). The MGN might even trigger SD in the first place by a failure in vasomotor control. As a consequence, migraine is considered as an inherently dynamical disease to which a linear course from upstream to downstream events would not do justice. Minimally invasive and noninvasive neuromodulation techniques are briefly reviewed and their rational is discussed in the context of the proposed mechanism.

Towards dynamical network biomarkers in neuromodulation of episodic migraine

Computational methods have complemented experimental and clinical neurosciences and led to improvements in our understanding of the nervous systems in health and disease. In parallel, neuromodulation in form of electric and magnetic stimulation is gaining increasing acceptance in chronic and intractable diseases. In this paper, we firstly explore the relevant state of the art in fusion of both developments towards translational computational neuroscience. Then, we propose a strategy to employ the new theoretical concept of dynamical network biomarkers (DNB) in episodic manifestations of chronic disorders. In particular, as a first example, we introduce the use of computational models in migraine and illustrate on the basis of this example the potential of DNB as early-warning signals for neuromodulation in episodic migraine.

Acute confusional migraine: a variant not to be missed

A middle age woman who had frequent migraines was admitted with memory loss following severe unilateral headache, restlessness and confusion. Investigations including haematology, biochemistry, cerebrospinal fluid analysis serology and imaging were normal. As she had frequent migraines with a history of ophthalmoplegic migraine, acute confusional migraine was thought of as a possibility. The patient responded dramatically to intravenous sodium valproate. We report this case to emphasise that acute confusional migraine, a rare variant of migraine, is occasionally encountered in adults and prompt recognition will lead to appropriate management.

The missing link: enhanced functional connectivity between amygdala and visceroceptive cortex in migraine

BACKGROUND

Migraine is a neurovascular disorder in which altered functional connectivity between pain-modulating circuits and the limbic system may play a role. Cortical spreading depression (CSD), which underlies migraine aura (MWA), induces C-fos expression in the amygdala. The role of CSD and amygdala connectivity in migraine without aura (MwoA) is less clear and may differentiate migraine from other chronic pain disorders.

METHODS

Using resting-state functional MRI, we compared functional connectivity between the amygdala and the cortex in MWA and MWoA patients as well as in healthy subjects and in two other chronic pain conditions not associated with CSD: trigeminal neuralgia (TGN) and carpal tunnel syndrome (CTS).

RESULTS

Amygdala connectivity in both MWA and MWoA was increased to the visceroceptive insula relative to all other groups examined.

CONCLUSION

The observed increased connectivity within the limbic/viscerosensory network, present only in migraineurs, adds to the evidence of a neurolimbic pain network dysfunction and may reflect repetitive episodes of CSD leading to the development of migraine pain.

The typical duration of migraine aura: a systematic review

BACKGROUND

According to ICHD-II, and as proposed for ICHD-III, non-hemiplegic migraine aura (NHMA) symptoms last between five and 60 minutes whereas hemiplegic migraine aura can be longer. In ICHD-III it is proposed to label aura longer than an hour and less than a week as probable migraine with aura. We tested whether this was appropriate based on the available literature.

METHODS

We performed a systematic literature search identifying articles pertaining to a typical or prolonged duration of NHMA. We also performed a comprehensive literature search in order to identify all population-based studies or case series in which clinical features of NHMA, including but not restricted to aura duration, were reported, in order to gain a complete coverage of the available scientific data on aura duration.

RESULTS

We did not find any article exclusively focusing on the prevalence of a prolonged aura or more generally on typical NHMA duration. We found 10 articles that investigated NHMA features, including the aura duration. Five articles recorded the proportion of patients in whom whole NHMA lasted for more than one hour, which was the case in 12%-37% of patients. Six articles reported some information on the duration of single NHMA symptoms: visual aura disturbances lasting for more than one hour occurred in 6%-10% of patients, sensory aura in 14%-27% of patients and aphasic aura in 17%-60% of patients.

CONCLUSIONS

The data indicate the duration of NHMA may be longer than one hour in a significant proportion of migraineurs. This seems to be especially true for non-visual aura symptoms. The term probable seems inappropriate in ICHD-III so we propose reinstating the category of prolonged aura for patients with symptoms longer than an hour and less than one week.

Underestimated phenomena: higher cortical dysfunctions during migraine aura

INTRODUCTION

Aura occurs in 20-30% of patients with migraine. Some descriptions of aura go far beyond the most frequent visual and sensory symptoms, suggesting the involvement of different cortical areas. The aim of this prospective study was to evaluate the frequency and types of disorders of higher cortical functions (HCF) that occur during visual and/or sensory aura.

METHODS

We interviewed 60 patients with visual and/or sensory aura about HCF disorders of praxia, gnosia, memory, and speech, during aura. Patients were divided into two groups, with and without HCF disorders, and were compared in terms of demographic data and aura characteristics.

RESULTS

From all 60 patients, 65% reported at least one HCF disorder during aura. The patients with HCF disorders had longer-lasting auras (28.51 ± 16.39 vs. 19.76 ± 11.23, P  = 0.016). The most common HCF disorders were motor dysphasia (82.05%) and dysnomia (30.74%). Motor dysphasia was more often reported by patients with visual as well as sensory aura ( P  = 0.002). The number of HCF disorders correlated with the aura duration ( P  = 0.003).

CONCLUSION

According to our results, HCF disorders during aura occur more often than previously thought. The aura duration has some influence on the HCF disorders.

Involvement of AMPA receptors in CSD-induced impairment of LTP in the hippocampus

OBJECTIVE

To investigate the alteration of hippocampal long-term plasticity and basal synaptic transmission induced by repetitive cortical spreading depressions (CSDs).

BACKGROUND

There is a relationship between migraine aura and amnesia attack. CSD, a state underlying migraine attacks, may be responsible for hippocampus-related symptoms. However, the precise role of CSD on hippocampal activity has not been investigated.

METHODS

Male Wistar rats were divided into CSD and control groups. Repetitive CSDs were induced in vivo by topical application of solid KCl. Forty-five minutes later, the ipsilateral hippocampus was removed, and hippocampal slices were prepared for a series of electrophysiological studies.

RESULTS

Repetitive CSDs led to a decrease in the magnitude of long-term potentiation in the hippocampus. CSD also reduced hippocampal synaptic efficacy, as shown by a reduction in post-synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor responses. In contrast, the post-synaptic N-methyl-d-aspartate receptor responses remained unchanged. In addition, there were no changes in paired-pulse profiles between the groups, indicating that CSD did not induce any presynaptic alterations.

CONCLUSION

These findings suggest that a reduction of post-synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor responses is the mechanism responsible for impaired hippocampal long-term potentiation induced by CSD.

Acute confusional migraine: our knowledge to date

Acute confusional migraine (ACM) is a rare migraine variant, affecting children and adolescents, as well as adults. Between 0.45 and 7.8% of children with migraine present with ACM, but the disorder may well be underdiagnosed. ACM is an exclusion diagnosis and some dangerous causes of confusion (e.g., epilepsy, ischemia, hemorrhagia, neoplasm, intoxication and encephalitis) should be ruled out. The confusional state often manifests with a wide diversity of cortical dysfunctions, such as speech difficulties, increased alertness, agitation and amnesia. Exact history taking, clinical examination, and laboratory, radiological and electroencephalographical findings lead the practitioner towards the diagnosis. Approximately half of the cases may be triggered by mild head trauma. Transient global amnesia is an important differential diagnosis, possibly caused by similar pathophysiological mechanisms. The exact pathomechanism remains unclear, with the common hypothesis comprising of the confusional state as a complex aura phenomenon, in which the cortical spreading depression wave reaches not only the occipital, but also the temporal, parietal and frontal cortex, as well as the brainstem and the hippocampi, leading to transient hypoperfusion and dysfunction of these brain areas.

Painful heat reveals hyperexcitability of the temporal pole in interictal and ictal migraine States

During migraine attacks, alterations in sensation accompanying headache may manifest as allodynia and enhanced sensitivity to light, sound, and odors. Our objective was to identify physiological changes in cortical regions in migraine patients using painful heat and functional magnetic resonance imaging (fMRI) and the structural basis for such changes using diffusion tensor imaging (DTI). In 11 interictal patients, painful heat threshold + 1°C was applied unilaterally to the forehead during fMRI scanning. Significantly greater activation was identified in the medial temporal lobe in patients relative to healthy subjects, specifically in the anterior temporal pole (TP). In patients, TP showed significantly increased functional connectivity in several brain regions relative to controls, suggesting that TP hyperexcitability may contribute to functional abnormalities in migraine. In 9 healthy subjects, DTI identified white matter connectivity between TP and pulvinar nucleus, which has been related to migraine. In 8 patients, fMRI activation in TP with painful heat was exacerbated during migraine, suggesting that repeated migraines may sensitize TP. This article investigates a nonclassical role of TP in migraineurs. Observed temporal lobe abnormalities may provide a basis for many of the perceptual changes in migraineurs and may serve as a potential interictal biomarker for drug efficacy.

The borderland of migraine with aura: episodic unilateral mydriasis

We present the case of a patient who had a 3-year history of episodes of transitory unilateral mydriasis with omolateral blurred vision followed by headache. Thereafter, during the last 4 years, the patient developed a migraine with visual aura, without further episodes of transitory mydriasis. We suggest that the transitory mydriasis previously present could be considered as an unusual form of migrainous aura. A possible pathogenetic mechanism is proposed.

One-year prevalence of migraine in Spain: A nationwide population-based survey

Aim

The purpose of the study was to estimate the one-year prevalence of migraine among a population-based sample of Spanish adults.

Method

Men and women aged 18-65 years were selected at random according to quotas for age, sex, size of habitat (10,000 inhabitants, 10,001–50,000 inhabitants, 50,001 −200,000 inhabitants and 200,000 inhabitants) and residence proportional to the population size of the geographical location. A random-digit-dial, computer-assisted telephone interview (CATI) survey was conducted between April and July 2006. The 2004 International Headache Society operational diagnostic criteria were applied.

Results

From a total of 70,692 telephone calls and 26,255 (31.7%) valid contacts, 5,668 (21.6%) respondents completed the CATI survey. A total of 476 subjects (8.4%, 95% confidence interval [CI] 7.7-9.1%) with strict migraine and 236 with probable migraine (4.2%, 95% CI 3.7-4.7%) were recorded. The 1-year prevalence of total migraine (N = 712) was 12.6% (95% CI 11.6-13.6) (17.2% in females, 8.0% in males). The prevalence rates showed significant geographic variations, from 7.6% in Navarra to 18% in the Canary Islands. One-half of the subjects had migraine with aura. One-third of subjects were never diagnosed for migraine.

Conclusions

The one-year prevalence of migraine in Spain is 12.6%, with a prevalence of migraine with and without aura of 8.4% and probable migraine of 4.2%. These findings add data to the current understanding of migraine.

Confusional migraine is an adult as well as a childhood disease

Background: Acute confusional migraine (ACM) is considered a rare migraine variant primarily seen in children and adolescents.

Patients and Methods: We present a series of eight adults and two adolescents suffering from migraine attacks associated with transient confusional states.

Results: Eight patients reported two or more such attacks. One of them reported mild head trauma in the past. One patient reported mild head trauma as a possible trigger. Further investigations were unremarkable in all patients and did not suggest underlying structural abnormalities, epilepsy or cerebrovascular disease. In none of these patients did we find another cause to explain the observed phenomenon.

Conclusions: Based on this series of patients, we suggest expanding the concept of confusional migraine from the paediatric population to adults. The temporal course of the confusion as well as the association with visual and other aura symptoms suggest cortical spreading depression as the underlying pathophysiology.

Recurrent Wernicke's aphasia: migraine and not stroke!

We report the clinical findings of a 40-year-old woman with recurrent migraine presenting with Wernicke's aphasia in accordance with the results of a standardized battery for language assessment (Boston Aphasia Diagnostic Examination). The patient had no evidence of parenchymal or vascular lesions on MRI and showed delta and theta slowing over the left posterior temporal leads on the EEG. Although the acute onset of a fluent aphasia suggested stroke as a likely etiology, the recurrence of aphasia as the initial symptom of migraine was related to cortical spreading depression and not to stroke.

A Note on the Digiti Quinti Sign in Hemiplegic Migraine

The digiti quinti sign (DQS) was described as an indication of mild hemiparesis. It consists of a wider space between the fourth and fifth fingers at the affected side when the patient extends both arms horizontally to the front with the palms down. The three successively examined sporadic hemiplegic migraine patients presented herein disclosed no other neurological abnormality except the interictally present DQS on the same side of the motor deficits. This sign is perhaps clinically useful for the diagnosis of hemiplegic migraine.

Migraine aura: retracting particle-like waves in weakly susceptible cortex

Cortical spreading depression (SD) has been suggested to underlie migraine aura. Despite a precise match in speed, the spatio-temporal patterns of SD observed in animal cortex and aura symptoms mapped to the cortical surface ordinarily differ in aspects of size and shape. We show that this mismatch is reconciled by utilizing that both pattern types bifurcate from an instability point of generic reaction-diffusion models. To classify these spatio-temporal pattern we suggest a susceptibility scale having the value sigma = 1 at the instability point. We predict that human cortex is only weakly susceptible to SD (sigma<1), and support this prediction by directly matching visual aura symptoms with anatomical landmarks using fMRI retinotopic mapping. Moreover, we use retinal SD to give a proof of concept of the existence of this instability point and describe how cortical susceptibility to SD must be adjusted for migraine drug testing. Close to the instability point at sigma = 1 the dynamical repertoire of cortical tissue is increased. As a consequence, the picture of an engulfing SD that became paradigmatic for migraine with aura needs to be modified in most cases towards a more spatially confined pattern that remains within the originating major gyrus or sulcus. Furthermore, we discuss the resulting implications on migraine pharmacology that is hitherto tested in the regime (sigma>1), and potentially silent aura occurring below a second bifurcation point at sigma = 0 on the susceptible scale.

Migraine headaches: diagnosis and management

BACKGROUND

Patients often complain to their optometrist about their headaches, of which migraines are a common type. They may ask if their pain is from visual causes or whether the visual auras they experience are normal.

METHODS

The literature on migraine is reviewed to provide the optometrist with current information to manage these patients.

RESULTS

Included in the review are migraine epidemiology, pathophysiology, categorization, clinical presentation, diagnosis, and treatment.

CONCLUSION

Optometrists can help their migraine patients with a thorough examination, advice, proper referrals, and optical management when appropriate.

Current migraine management - patient acceptability and future approaches

Despite its high prevalence and individual as well as societal burden, migraine remains underdiagnosed and undertreated. In recent years, the options for the management of migraine patients have greatly expanded. A number of drugs belonging to various pharmacological classes and deliverable by several routes are now available both for the acute and the preventive treatments of migraine. Nevertheless, disability and satisfaction remain low in many subjects because treatments are not accessible, not optimized, not effective, or simply not tolerated. There is thus still considerable room for better education, for more efficient therapies and for greater support from national health systems. In spite of useful internationally accepted guidelines, anti-migraine treatment has to be individually tailored to each patient taking into account the migraine subtype, the ensuing disability, the patient's previous history and present expectations, and the co-morbid disorders. In this article we will summarize the phenotypic presentations of migraine and review recommendations for acute and preventive treatment, highlighting recent advances which are relevant for clinical practice in terms of both diagnosis and management.

Neuro-ophthalmologic manifestations of primary headache disorders

Headaches are the most common disorders of the central nervous system affecting 46% of the adult population worldwide. Headaches may be lifelong illnesses, often associated with substantial disability for the individual and the population as a whole. The International Classification of Headache Disorders (ICHD-II) codifies headache disorders into fourteen categories, predominantly primary headaches and secondary headache disorders. Primary headache disorders, mainly migraine and trigeminal autonomic cephalgias (TACs), are frequently associated with neuro-ophthalmologic manifestations. Ophthalmologists are often the first physicians to be involved in the deciphering of headache-related visual disturbances. This article reviews two major primary headache disorders, migraine and trigeminal autonomic cephalgias, and discusses their neuro-ophthalmic complications, clinical presentation, and treatment.