Imaging abnormalities in sporadic hemiplegic migraine on conventional MRI, diffusion and perfusion MRI and MRS

Clinical characteristics and perfusion-computed tomography alterations in a series of patients with migraine with aura attended as stroke code

OBJECTIVE

The aim of the current study was to determine the clinical characteristics of migraine with aura (MA) as well as the frequency and patterns of perfusion-computed tomography (PCT) alterations, in a series of patients with MA mimicking acute ischemic stroke.

BACKGROUND

MA is one of the most frequent stroke mimics, following seizures and psychiatric disorders. Previous case reports and short series have reported abnormal PCT patterns in patients with MA.

METHODS

We conducted a retrospective cohort study including all consecutive patients presenting with focal neurological symptoms during complete multimodal CT including baseline CT, angio-CT, and PCT with a final diagnosis of MA. We collected demographic data and clinical information about MA variables using the hospital electronic database.

RESULTS

We found 25 patients with a final diagnosis of MA among 1761 patients who attended our stroke center with complete multimodal CT (1.4% [95% CI: 0.9-2.1]). Among them, 14/25 (56%) were women, average age 38.7 years (SD 12.5), and 16/25 (64%) had a previous history of migraine. The most frequent type of aura was sensory. The median time elapsed between the onset of symptoms and CT was 171 min (IQR: 119-244). PCT alteration was found in 3/25 (12%) consisting of a hypoperfusion pattern not restricted to a vascular territory. The three patients had aphasia as the presenting symptom.

CONCLUSION

This is, to the best of our knowledge, the largest series of patients with MA managed as presumed stroke with clinical characteristics and PCT. In our study, most patients were young and had a prior history of migraine. PCT was normal in 88% of cases, with patients being still symptomatic by the time they were scanned. Further research will clarify the presence and type of PCT alterations in this entity.

Prolonged Hemiplegic Migraine Led to Persistent Hyperperfusion and Cortical Necrosis: Case Report and Literature Review

Hemiplegic migraine (HM) is a rare subtype of migraine characterized by aura of motor weakness accompanied by visual, sensory, and/or speech symptoms. Aura symptoms usually resolve completely; permanent attack-related deficit and radiographic change were rare. Here, we reported a case presented with progressively aggravated hemiplegic migraine episodes refractory to medication. He experienced two prolonged hemiplegic migraine attacks that led to irreversible visual impairment and cortical necrosis on brain MRI. Multimodal MRI during attack showed persistent vasodilation and hyperperfusion in the affected hemisphere associated with deterioration of clinical symptoms and worsening of brain edema. Patent foramen ovale (PFO) was found on the patient. PFO closure resulted in a significant reduction of HM attacks. This case indicated that prolonged hemiplegic migraine attack could result in irreversible neurological deficit with radiographic changes manifested as cortical necrosis. Persistent hyperperfusion might be an important factor contributing to prolonged attack and persistent attack-related neurological deficit. We recommend screening for PFO in patients with prolonged or intractable hemiplegic migraine, for that closure of PFO might alleviate the attacks thus preventing the patient from disabling sequelae.

Cortical excitability in migraine: Contributions of magnetic resonance imaging

Migraine is characterized by symptoms related to cortical hyperexcitability such as photophobia, phonophobia, osmophobia and allodynia. One-third of migraineurs experience aura, whose neurophysiological substrate is thought to be cortical spreading depression (CSD). Functional magnetic resonance imaging (MRI) has shown the migraine aura to be characterized by cerebral hyperactivity/hyperperfusion followed by hypometabolism/hypoperfusion spreading along the occipital cortex with the same spatiotemporal organization as the experimentally triggered CSD. The link between migraine aura and headache remains undetermined. Neuroimaging studies have failed to show a leakage of the blood-brain barrier, which was suspected to occur during CSD and to cause the stimulation of trigeminal nociceptive receptors. However, recent studies have highlighted the involvement of neuroglial inflammation and other studies have suggested that a common central network plays a role in the link between CSD and migraine pain. Finally, MRI has made it possible to study the contribution of metabolites such as glutamic acid, γ-amino-butyric acid and sodium in the pathophysiology of hyperexcitability in migraine.

Assessment of normalized cerebral blood flow and its connectivity with migraines without aura during interictal periods by arterial spin labeling

BACKGROUND

Migraine constitutes a global health burden, and its pathophysiology is not well-understood; research evaluating cerebral perfusion and altered blood flow between brain areas using non-invasive imaging techniques, such as arterial spin labeling, have been scarce. This study aimed to assess cerebral blood flow (CBF) and its connectivity of migraine.

METHODS

This study enrolled 40 patients with episodic migraine without aura (MwoA), as well as 42 healthy patients as control (HC). Two groups of normalized CBF and CBF connectivity were compared, and the relationship between CBF variation and clinical scale assessment was further evaluated.

RESULTS

In comparison to HC subjects, MwoA patients exhibited higher CBF in the right middle frontal orbital gyrus (ORBmid.R) and the right middle frontal gyrus, while that in Vermis_6 declined. The increased CBF of ORBmid.R was positively correlated with both the Visual Light Sensitivity Questionnaire-8 (VLSQ-8) and the monthly attack frequency score. In MwoA, significantly decreased CBF connectivity was detected between ORBmid.R and the left superior frontal gyrus, the right putamen, the right caudate, as well as the right angular gyrus. In addition, increased CBF connectivity was observed between the left calcarine cortex and ORBmid.R.

CONCLUSIONS

Our results indicate that migraine patients exhibit abnormalities in regional CBF and feature CBF connection defects at the resting state. The affected areas involve information perception, information integration, and emotional, pain and visual processing. Our findings might provide important clues for the pathophysiology of migraine.

Altered Metabolites in the Occipital Lobe in Migraine Without Aura During the Attack and the Interictal Period

Background: Although there have been many magnetic resonance spectroscopy (MRS) studies of migraine, few have focused on migraines during an attack. Here, we aimed to assess metabolite changes in the brain of patients with migraine, both during an attack and in the interictal phase.

Methods: Six patients (one man and five women, mean age: 39 ± 10 years) with migraine without aura during the attack (MWoA-DA), 13 patients (three men and 10 women, mean age: 31 ± 9 years) with migraine without aura during the interictal period (MWoA-DI), and 13 healthy controls (HC) (four men and nine women, mean age: 31 ± 9 years) were studied. All subjects underwent an MRS examination focusing on the occipital lobe. Metabolite changes were investigated among three groups.

Results: The MWoA-DA patients had lower glutathione/total creatine ratio (GSH/tCr) than the MWoA-DI patients and HC. Furthermore, MWoA-DI patients showed lower total choline/total creatine ratio (tCho/tCr) than those in the other two groups. The GSH/tCr ratio was positively correlated with attack frequency in the MWoA-DI group. The tCho/tCr ratio was positively correlated with attack frequency and Migraine Disability Assessment Scale (MIDAS) scores in the MWoA-DA group.

Conclusion: The present study suggests the existence of distinct pathophysiological states between the MWoA-DA and MWoA-DI groups. Neuronal dysfunction is a possible predisposing factor for migraine attack onset, along with oxidative stress and inflammation.

Cortical glutamate and gamma-aminobutyric acid over the course of a provoked migraine attack, a 7 Tesla magnetic resonance spectroscopy study

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7T MRS separately measured glutamate, glutamine and GABA towards triggered attacks.

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Visual cortex GABA levels increased towards a preictal migraine state.

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Visual cortex glutamate and glutamine levels were stable across migraine states.

Enhanced activity of the glutamatergic system has been linked to migraine pathophysiology. The present study aimed to assess the involvement of the glutamatergic system in the onset of attacks. We provoked attacks by infusion of glyceryl trinitrate (GTN; 0.5 µg/kg/min over 20 min) in 24 female episodic migraineurs without aura and 13 female age-matched healthy controls. Over the course of a single day participants were scanned three times at fixed time slots (baseline before GTN infusion, 90 min and 270 min after start of GTN infusion). Single-volume proton magnetic resonance spectra (¹H–MRS) were acquired at 7 Tesla from a volume of interest (VOI, 2x2x3 cm) in the visual cortex. We assessed the concentrations of glutamate, its major precursor glutamine, and its product gamma-aminobutyric acid (GABA) over the course of a provoked attack. The preictal state was defined as the period after GTN infusion until the migraine-like headache started, independent of possible experienced premonitory symptoms, and the ictal state was defined as the period with provoked migraine-like headache. Data were analyzed using a linear mixed-effect model for repeated measures. Glutamate and glutamine levels did not change from interictal to the preictal and ictal state. GABA levels increased from interictal towards the preictal state for migraine patients compared with healthy controls. We conclude that high resolution 7T MRS is able to show changes in the glutamatergic system towards a triggered migraine attack, by revealing an increased GABA concentration associated with the onset of a migraine attack.

Diagnostic and therapeutic aspects of hemiplegic migraine

Hemiplegic migraine (HM) is a clinically and genetically heterogeneous condition with attacks of headache and motor weakness which may be associated with impaired consciousness, cerebellar ataxia and intellectual disability. Motor symptoms usually last <72 hours and are associated with visual or sensory manifestations, speech impairment or brainstem aura. HM can occur as a sporadic HM or familiar HM with an autosomal dominant mode of inheritance. Mutations in CACNA1A, ATP1A2 and SCN1A encoding proteins involved in ion transport are implicated. The pathophysiology of HM is close to the process of typical migraine with aura, but appearing with a lower threshold and more severity. We reviewed epidemiology, clinical presentation, diagnostic assessment, differential diagnosis and treatment of HM to offer the best evidence of this rare condition. The differential diagnosis of HM is broad, including other types of migraine and any condition that can cause transitory neurological signs and symptoms. Neuroimaging, cerebrospinal fluid analysis and electroencephalography are useful, but the diagnosis is clinical with a genetic confirmation. The management relies on the control of triggering factors and even hospitalisation in case of long-lasting auras. As HM is a rare condition, there are no randomised controlled trials, but the evidence for the treatment comes from small studies.

A novel computed tomography perfusion-based quantitative tool for evaluation of perfusional abnormalities in migrainous aura stroke mimic

BACKGROUND

Migrainous aura (MA) represents the third most common stroke mimic (SM). Advanced neuroimaging is pivotal in the assessment of patients with focal neurological acute symptoms. We investigated brain perfusion alterations in MA-SM patients using a novel CT perfusion (CTP)-based quantitative approach in order to improve differential diagnosis between MA and acute stroke.

METHODS

We processed and analysed the clinical and neuroimaging CTP data, acquired within 4.5 h from symptom onset, of patients with acute focal neurological symptoms receiving a final diagnosis of MA. The differences between ROI, compatible with MA symptoms, and contralateral side were automatically estimated in terms of asymmetry index (AI%) by the newly developed tool for mean transit time (MTT), CBF, and cerebral blood volume (CBV) CTP parameters. The AI% ≥ 10% was considered significant.

RESULTS

Out of 923 admitted patients, 14 patients with MA were included. In 13 out of 14 cases, a significant pattern of hypoperfusion was observed by quantitative analysis in at least one of the CTP maps. In 7 patients, all three CTP maps were significantly altered. In particular, MTT-AI% increased in 11 (79%) cases, while CBF-AI% and CBV-AI% decreased in 12 (86%) and in 9 (64%) patients, respectively. All CBV values were above ischemic stroke core threshold and all MTT-AI were below ischemic penumbra threshold.

CONCLUSIONS

Our data suggest that a novel CTP-quantitative approach may detect during MA a moderate hypoperfusion pattern in the cerebral regions compatible with aura symptoms. The use of this novel tool could support differential diagnosis between MA and acute stroke.

Interrelated Pathogenesis? Neuronal Intranuclear Inclusion Disease Combining With Hemiplegic Migraine

BACKGROUND

Neuronal intranuclear inclusion disease (NIID) is considered a heterogeneous disease because of its highly variable clinical manifestations. To date, there are no reports of NIID patients presenting with hemiplegic migraine (HM)-like headache, or of HM and NIID co-occurring as comorbidity, and the connection between these 2 seemingly unrelated clinical conditions has yet to be established.

METHOD

We present a patient with NIID who was previously diagnosed with HM. To determine the pathogenesis of HM in this NIID patient, we systematically reviewed published NIID and HM cases and cataloged them based on their clinical manifestations.

RESULT

The clinical manifestations of NIID is highly various; however, there is no case reported to date that shows HM-like symptoms or cerebral edema. All documented symptomatic HM cases show vascular dysfunction to various degrees, but none of them has been shown to be correlated with NIID.

CONCLUSION

Our patient is the first documented case in which HM and NIID occur simultaneously. Vascular dysfunctions that cause cerebral hypoperfusion and glucose hypometabolism, two of the dominant causes of symptomatic HM, may be associated with the accumulation of eosinophilic hyaline inclusions that cause NIID. However, the existence of inclusions may also alter neuronal behavior and indirectly cause cerebral hypoperfusion and glucose hypometabolism. Further research and observations are needed to examine the relationship between HM and NIID.

White Matter Hyperintensities in Patients with Sporadic Hemiplegic Migraine

BACKGROUND AND PURPOSE

To identify the differences in overall occurrence, location, and disease burden of white matter hyperintensities (WMH) in patients with sporadic hemiplegic migraine (SHM) and patients with migraine headaches.

METHODS

We included patients who met diagnostic criteria proposed by the third International Classification of Headache Disorders (ICHD-3) for SHM and migraine headache. WMHs were identified using T2 fluid-attenuated inversion recovery axial sequence and classified based upon the location. The disease burden was assessed using Scheltens visual rating scale.

RESULTS

Fifty patients met the diagnostic criteria for SHM and 100 patients for migraine headache. Patients in the study group were similar to the control group in terms of age (47.7 ± 12.2 years vs. 48.17 ± 9.7 years; P = .814) and gender (M: F; 14:36 vs. M: F 25:75; P = .693). WMH were found in 28 (56%) patients with SHM and 44 (44%) in patients with migraine headache. The proportion of patients with WMH was not different between the two groups (P = .166). On univariate analysis, the proportion of patients with WMH in parietal, occipital, and infratentorial regions was higher in patients with SHM. White matter burden determined by visual rating scale and proportion of patients with lesions ≥5 mm in diameter was also significantly higher in patients with SHM. On multivariate analysis, the WMH occurrence in the parietal lobe (P = .043) was found to be significantly higher in SHM.

CONCLUSIONS

The WMH occurrence in patients with SHM is significantly more in the parietal lobe when compared to those with migraine headaches. WMH burden was also higher in patients with SHM, and larger white matter lesions occurred more frequently in these patients with SHM (compared to ordinary migraineurs).

Stroke-like migraine attacks after radiation therapy syndrome: Case report and review of the literature

A 26-year-old female presented with vision loss accompanied by migraine-like headaches. A contrast-enhanced magnetic resonance imaging of the brain was performed which revealed findings suggestive of stroke-like migraine attacks after radiation therapy (SMART) syndrome. SMART syndrome is a delayed complication of brain radiation characterized by neurologic symptoms including migraine-like headaches, seizures, and hemispheric impairment. The purpose of this article is to make the readers aware of this rare complication of brain irradiation. Appropriate diagnosis of SMART syndrome is essential to avoid invasive tests.

Understanding the Neurophysiology and Quantification of Brain Perfusion

Newer neuroimaging technology has moved beyond pure anatomical imaging and ventured into functional and physiological imaging. Perfusion magnetic resonance imaging (PWI), which depicts hemodynamic conditions of the brain at the microvascular level, has an increasingly important role in clinical central nervous system applications. This review provides an overview of the established role of PWI in brain tumor and cerebrovascular imaging, as well as some emerging applications in neuroimaging. PWI allows better characterization of brain tumors, grading, and monitoring. In acute stroke imaging, PWI is utilized to distinguish penumbra from infarcted tissue. PWI is a promising tool in the assessment of neurodegenerative and neuropsychiatric diseases, although its clinical role is not yet defined.

A case report of sporadic hemiplegic migraine associated cerebral hypoperfusion: comparison of arterial spin labeling and dynamic susceptibility contrast perfusion MR imaging

The pathogenesis of sporadic hemiplegic migraine remains unclear, and perfusion-weighted magnetic resonance imaging (PWI) has been used for characterization of hemodynamic changes in migraine aura. We report a case of sporadic hemiplegic migraine in which magnetic resonance perfusion imaging showed left cerebral hypoperfusion. Dynamic susceptibility contrast (DSC) perfusion maps showed hypoperfusion with posterior predominance in the left cerebral hemisphere. Findings with arterial spin labeling (ASL) perfusion correlated well with DSC perfusion findings.

CONCLUSION

With unique advantages compared with DSC PWI, ASL has significant potential in the evaluation of the patients with sporadic hemiplegic migraine.

WHAT IS KNOWN

Sporadic hemiplegic migraine is a rare variety of migraine defined by migraine attacks, which include the presence of motor weakness/hemiparesis during the aura phase and where no first- or second-degree relative (parent, sibling, or child) has identical attacks.

WHAT IS NEW

Reports on imaging abnormalities described in sporadic hemiplegic migraine are sparse. To our knowledge, this is the first report to describe arterial spin labeling (ASL) perfusion abnormalities in patients with sporadic hemiplegic migraine, as compared with dynamic susceptibility contrast perfusion-weighted magnetic resonance imaging (PWI).

Recurrent steroid-responsive cerebral vasogenic edema in status migrainosus and persistent aura

Background

Status migrainosus (SM) and persistent aura (PA) without infarction are complications of migraine. Although several patients have been reported to have reversible brain lesions associated with complications of migraine, their nature and pathophysiology remain unclear.

Case

We report on a 38-year-old male who presented with nine episodes of SM and PA over eight years. Serial neuroimaging studies including brain magnetic resonance imaging (MRI), blood flow single photon emission tomography (SPECT),18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) and11 C-flumazenil PET (FMZ-PET) demonstrated cerebral vasogenic edema (CVE) with hypoperfusion and hypometabolism in the area, anatomically corresponding to the area with PA. SM and PA were effectively controlled by corticosteroid therapy. Follow-up MRI revealed complete reversibility of the CVE, which was supported by normal FMZ-PET and FDG-PET findings.

Conclusion

We have described a patient with transient brain lesions associated with complications of migraine who was diagnosed with fully reversible and steroid responsive CVE.

Perfusion patterns in migraine with aura

OBJECTIVES

Migraine with aura is a common neurological disorder, and differentiation from transient ischemic attack or stroke based on clinical symptoms may be difficult.

METHODS

From an MRI report database we identified 33 patients with migraine with aura and compared these to 33 age-matched ischemic stroke patients regarding perfusion patterns on perfusion-weighted imaging (PWI)-derived maps: time to peak (TTP), mean transit time (MTT), and cerebral blood flow and volume (CBF, CBV).

RESULTS

In 18/33 (54.5%) patients with migraine with aura, TTP showed areas of hypoperfusion, most of these not limited to the territory of a specific artery but affecting two or more vascular territories. In patients with migraine with aura, TTP (1.09 ± 0.05 vs. 1.47 ± 0.40, p < 0.001) and MTT ratios (1.01 ± 0.10 vs. 1.19 ± 0.21, p = 0.003) were significantly lower compared to patients with ischemic stroke. In contrast to this, CBF and CBV ratios did not differ significantly between both groups.

CONCLUSIONS

Migraine aura is usually associated with a perfusion deficit not limited to a specific vascular territory, and only a moderate increase of TTP. Thus, hypoperfusion restricted to a single vascular territory in combination with a marked increase of TTP or MTT may be regarded as atypical for migraine aura and suggestive of acute ischemic stroke.

The diagnostic role for susceptibility-weighted MRI during sporadic hemiplegic migraine

Background

Hemiplegic migraine is a rare form of migraine with aura that includes motor weakness. Diagnosis during the first episode can be difficult to make and costly, especially with the sporadic form.

Cases

Our study evaluates the ictal magnetic resonance imaging (MRI) features of four sequential pediatric patients during a first-time, sporadic hemiplegic migraine. Susceptibility-weighted imaging (SWI) revealed cerebral venous prominence and increased magnetic susceptibility affecting brain regions that corresponded with each patient’s neurologic deficits. Repeat MRI (performed in three patients) following migraine recovery demonstrated resolution of all susceptibility abnormalities.

Conclusion

When combined with conventional MRI sequences, SWI has diagnostic value in the acute setting of motor weakness and with clinical features consistent with hemiplegic migraine. The sequence may help to further characterize ictal cerebral blood flow changes during the hemiplegic migraine aura.

Familial and sporadic hemiplegic migraine: diagnosis and treatment

OPINION STATEMENT

Hemiplegic migraine (HM) is a rare subtype of migraine with aura, characterized by transient hemiparesis during attacks. Diagnosis is based on the International Classification of Headache Disorders criteria (ICHD-II). Two types of HM are recognized: familial (FHM) and sporadic hemiplegic migraine (SHM). HM is genetically heterogeneous. Three genes have been identified (CACNA1A, ATP1A2, and SCN1A) but more, so far unknown genes, are involved. Clinically, attacks of the 3 subtypes cannot be distinguished. The diagnosis can be confirmed but not ruled out by genetic testing, because in some HM patients other, not yet identified, genes are involved. The presence of additional symptoms (such as chronic ataxia or epilepsy) may increase the likelihood of identifying a mutation. Additional diagnostics like imaging, CSF analysis, or an EEG are mainly performed to exclude other causes of focal neurological symptoms associated with headache. Conventional cerebral angiography is contraindicated in HM because this may provoke an attack. Because HM is a rare condition, no clinical treatment trials are available in this specific subgroup of migraine patients. Thus, the treatment of HM is based on empirical data, personal experience of the treating neurologist, and involves a trial-and-error strategy. Acetaminophen and NSAIDs often are the first choice in acute treatment. Although controversial in HM, triptans can be prescribed when headaches are not relieved sufficiently with common analgesics. An effective treatment for the severe and often prolonged aura symptoms is more warranted, but currently no such acute treatment is available. Prophylactic treatment can be considered when attack frequency exceeds 2 attacks per month, or when severe attacks pose a great burden that requires reduction of severity and frequency. In no strictly preferred order, flunarizine, sodium valproate, lamotrigine, verapamil, and acetazolamide can be tried. While less evidence is available for prophylactic treatment with topiramate, candesartan, and pizotifen, these drugs can also be considered. The use of propranolol in HM is more controversial, but evidence of adverse effects is insufficient to contraindicate beta-blockers.

Magnetic resonance spectroscopy in migraine: what have we learned so far?

OBJECTIVE

To summarize and evaluate proton ((1)H) and phosphorus ((31)P) magnetic resonance spectroscopy (MRS) findings in migraine.

METHODS

A thorough review of (1)H and/or (31)P-MRS studies in any form of migraine published up to September 2011.

RESULTS

Some findings were consistent in all studies, such as a lack of ictal/interictal brain pH change and a disturbed energy metabolism, the latter of which is reflected in a drop in phosphocreatine content, both in the resting brain and in muscle following exercise. In a recent interictal study ATP was found to be significantly decreased in the occipital lobe of migraine with aura patients, reinforcing the concept of a mitochondrial component to the migraine threshold, at least in a subgroup of patients. In several studies a correlation between the extent of the energy disturbance and the clinical phenotype severity was apparent. Less consistent but still congruent with a disturbed energy metabolism is an observed lactate increase in the occipital cortex of several migraine subtypes (MwA, migraine with prolonged aura). No increases in brain glutamate levels were found.

CONCLUSION

The combined abnormalities found in MRS studies imply a mitochondrial component in migraine neurobiology. This could be due to a primary mitochondrial dysfunction or be secondary to, for example, alterations in brain excitability. The extent of variation in the data can be attributed to both the variable clinical inclusion criteria used and the variation in applied methodology. Therefore it is necessary to continue to optimize MRS methodology to gain further insights, especially concerning lactate and glutamate.

Cerebral perfusion changes in migraineurs: a voxelwise comparison of interictal dynamic susceptibility contrast MRI measurements

INTRODUCTION

The increased risk of cerebro- and cardiovascular disease in migraineurs may be the consequence of a systemic condition affecting whole body vasculature. At cerebrovascular level, this may be reflected by interictal global or regional cerebral perfusion abnormalities. Whether focal perfusion changes occur during interictal migraine has not been convincingly demonstrated.

METHODS

We measured brain perfusion with dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in 29 interictal female migraineurs (12 migraine with aura (MA), 17 migraine without aura (MO)), and 16 female controls. Perfusion maps were compared between these groups with a voxelwise (p < 0.001, uncorrected, minimum cluster size 20 voxels) and a region-of-interest approach.

RESULTS

In whole brain voxelwise analyses interictal hyperperfusion was observed in the left medial frontal gyrus in migraineurs and in the inferior and middle temporal gyrus in MO patients, in comparison with controls. Hypoperfusion was seen in the postcentral gyrus and in the inferior temporal gyrus in MA patients and in the inferior frontal gyrus in MO patients. Additional focal sites of hyperperfusion were noted in subgroups based on attack frequency and disease history. Region-of-interest analyses of the pons, hypothalamus, occipital lobe, and cerebellum did not show interictal perfusion differences between migraineurs and controls.

CONCLUSIONS

We conclude that interictal migraine is characterized by discrete areas of hyper- and hypoperfusion unspecific for migraine pathophysiology and not explaining the increased vulnerability of particular brain regions for cerebrovascular damage.

Sporadic hemiplegic migraine with seizures and transient MRI abnormalities

Hemiplegic migraines are characterised by attacks of migraine with aura accompanied by transient motor weakness. There are both familial and sporadic subtypes, which are now recognised as separate entities by the International Classification of Headache Disorders, edition II (ICHD-II). Sporadic hemiplegic migraine is a rare variant of migraine, We report a case of sporadic hemiplegic migraine and seizures with MRI features suggestive of cortical hyper intensity and edema on T2 and FLAIR images with no restriction pattern on diffusion and these changes completely resolving over time, suggesting that these changes are due prolonged neuronal depolarization and not of ischemic origin.

Multimodal neuroimaging in a child with sporadic hemiplegic migraine: A contribution to understanding pathogenesis

Background: Hemiplegic migraine (HM) is a rare variety of migraine with aura, characterized by motor deficits during the aura, often beginning in childhood. The hemiplegic attacks can be severe and prolonged but the prognosis is usually good. Data on neuroimaging, including diffusion-weighted imaging (DWI) and spectroscopy, during prolonged attacks of HM are quite limited, particularly in children.

Case: An eight-year-old female had a prolonged attack of sporadic HM characterized by right-sided hemiplegia, global aphasia, fever and impairment of consciousness. MRI nine hours after hemiplegia onset was negative, while the following MRI scans (days 4 and 11) documented a progressive increase in cortical swelling in the left hemisphere with mild hyperintensity on DWI and mild reduction of apparent diffusion coefficient values. Proton MRI spectroscopy (MRS) (day 15) showed a decrease in the N-acetylaspartate/creatine ratio in the left hemisphere. 99mTc-ECD single-photon emission tomography (SPET) (day 27) showed marked left hemispheric hypoperfusion. The patient recovered completely after 40 days and neuroimaging follow-up (MRI and SPET) after six months was normal. The patient carried a missense mutation of the ATP1A2 gene.

Conclusion: Multimodal neuroimaging (MRI, DWI, MRS, SPET) in a prolonged HM attack supports evidence for a primary neuronal dysfunction.

(1)H-MRS of brain metabolites in migraine without aura: absolute quantification using the phantom replacement technique

OBJECTIVE

Several studies have demonstrated differences in migraine patients when performing (1)H-MRS; however, no studies have performed (1)H-MRS in migraine without aura (MwoA), the most common migraine subtype. The aim of this (1)H-MRS study was to elucidate whether any differences could be found between MwoA patients and controls by performing absolute quantification.

MATERIALS AND METHODS

(1)H-MRS was performed in 22 MwoA patients and 25 control subjects. Absolute quantification was based on the phantom replacement technique. Corrections were made for T (1) and T (2) relaxation effects, CSF content, coil loading and temperature. The method was validated by phantom measurements and in vivo measurements in the occipital visual cortex.

RESULTS

After calibration of the quantification procedure and the implementation of the required correction factors, measured absolute concentrations in the visual cortex of MwoA patients showed no significant differences compared to controls, in contrast to relative results obtained in earlier studies.

CONCLUSION

In this study, we demonstrate the implementation of quantitative in vivo (1)H-MRS spectroscopy in migraine patients. Despite rigorous quantification, no spectroscopic abnormalities could be found in patients with migraine without aura.

Abnormal MRI in a patient with 'headache with neurological deficits and CSF lymphocytosis (HaNDL)'

A 27-year-old woman was admitted to the Emergency Department with right upper-extremity numbness and mild weakness followed by a bifrontal throbbing headache for 30 min, which was similar to a headache lasting for 12 h that had occurred 3 days ago. Laboratory tests were unremarkable except for cerebrospinal fluid (CSF) lymphocytic pleocytosis. On the following day, a headache episode with left hemiparesis and hemihypoaesthesia, left hemifield visio-spatial inattention, anosagnosia and confusion recurred. The headache was diagnosed as headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) syndrome according to the criteria of the second edition of the International Classification of Headache Disorders. Simultaneously performed magnetic resonance imaging (MRI) revealed swelling of the grey matter, CSF enhancement in the sulci of the right temporal and occipital regions and hypoperfusion of the same brain regions. During the following 10 days two more similar episodes recurred and during the ensuing 12 months the patient remained headache free. Neuroimaging findings of the HaNDL syndrome are always thought as virtually normal. MRI abnormalities in our patient have not been reported in HaNDL syndrome previously, although they have been reported in hemiplegic migraine patients before. The findings in our case suggest that hemiplegic migraine and HaNDL syndrome may share a common pathophysiological pathway resulting in similar imaging findings and neurological symptoms.

Arterial spin-labeled MR perfusion imaging: clinical applications

Arterial spin labeling (ASL) imaging soon will be available as a routine clinical perfusion imaging sequence for a significant number of MR imaging scanners. The ASL perfusion technique offers information similar to that provided by conventional dynamic susceptibility sequences, but it does not require the use of an intravenous contrast agent, and the data can be quantified. The appearance of pathology is affected significantly by the ASL techniques used. Familiarity with the available sequence parameter options and the common appearances of pathology facilitates perfusion interpretation.

Sporadic hemiplegic migraine: report of a case with clinical and radiological features

A case of visual hallucination, headache and left hemiparesis is reported. The patient had a history of recurrent attacks of similar semiology for the previous 15 years. MRI brain revealed a cortical hyperintensity on T2W, FLAIR and diffusion weighted imaging (DWI) in the right cerebral hemisphere with a normal ADC (apparent diffusion coefficient) map and MR angiogram. Detailed workup for MELAS was negative. A diagnosis of sporadic hemiplegic migraine was made and he was managed conservatively. He made a gradual complete recovery over 2 weeks. He was discharged on flunarizine for prophylaxis and has remained asymptomatic over the ensuing 4 months. This interesting condition is reviewed and discussed herein.

Migraine associated cerebral hyperperfusion with arterial spin-labeled MR imaging

We present a case series demonstrating abnormal regional cerebral hyperperfusion associated with migraine headache using arterial spin-labeling (ASL). In 3 of 11 patients, regional cortical hyperperfusion was demonstrated during a headache episode that corresponded to previous aura symptoms.

Prolongierte Migräneaura vs. akuter ischämischer Insult

BACKGROUND

According to the "time is brain" concept, differential diagnosis of acute stroke and prolonged migrainous aura is of vital importance in this era of systemic thrombolysis for acute cerebral ischemia. We demonstrate the value of cerebral magnetic resonance imaging (cMRI) in acute situations by presenting two patients.

PATIENTS AND METHODS

Two patients were sent to our hospital for lysis treatment after the sudden appearance of global aphasia and slight right-sided hemiparesis. Further exploration was impossible due to the aphasia, and therefore we performed diffusion- and perfusion-weighted cMRI.

RESULTS

We excluded acute cerebral infarction by the aid of diffusion-weighted cMRI, however left-sided cerebral hypoperfusion was seen in both patients. After resolution of neurologic symptoms, unilateral headache occurred and both patients reported pre-existing migraine with aura.

CONCLUSION

Hypoperfusion of the malfunctioning brain region contralateral to the affected side of the body has been described on cMRI in only a few patients with prolonged migrainous aura. We conclude from our two cases that--provided rapid availability--cMRI can add important information for differential diagnosis, in particular when lysis therapy is a treatment option.

Migrainous infarction with appearance of laminar necrosis on MRI

Although there is accepted criteria for migrainous infarction, the pathophysiology of this disease process remains poorly defined. Delineation of MRI characteristics of migrainous infarction may improve our understanding of the pathophysiology, diagnosis, and prognosis of this disorder. We present a case of a migrainous infarction that involved apparent laminar necrosis of a "cortical ribbon" of the right temporal, parietal, and occipital lobes.