Aphasic and visual aura with increased vasogenic leakage: An atypical migrainosus status

Imaging the inflammatory phenotype in migraine

Several preclinical and clinical lines of evidence suggest a role of neuroinflammation in migraine. Neuroimaging offers the possibility to investigate and localize neuroinflammation in vivo in patients with migraine, and to characterize specific inflammatory constituents, such as vascular permeability, and macrophage or microglia activity. Despite all imaging data accumulated on neuroinflammation across the past three decades, an overview of the imaging evidence of neuroinflammation in migraine is still missing.We conducted a systematic review in the Pubmed and Embase databases to evaluate existing imaging data on inflammation in migraine, and to identify gaps in the literature. We included 20 studies investigating migraine without aura (N = 4), migraine with aura (N = 8), both migraine with and without aura (N = 3), or hemiplegic migraine (N = 5).In migraine without aura, macrophage activation was not evident. In migraine with aura, imaging evidence suggested microglial and parameningeal inflammatory activity. Increased vascular permeability was mostly found in hemiplegic migraine, and was atypical in migraine with and without aura. Based on the weight of existing and emerging data, we show that most studies have concentrated on demonstrating increased vascular permeability as a marker of neuroinflammation, with tools that may not have been optimal. In the future, novel, more sensitive techniques, as well as imaging tracers delineating specific inflammatory pathways may further bridge the gap between preclinical and clinical findings.

Biphasic neurovascular changes in prolonged migraine aura in familial hemiplegic migraine type 2

OBJECTIVE

To report biphasic changes in cerebral blood flow (CBF) in the acute phase of hemiplegic migraine with prolonged aura (HMPA), in which aura symptoms lasted longer than 24 h, in three patients with familial hemiplegic migraine (FHM) carrying a p.H916L mutation in ATP1A2 gene.

METHODS

We assessed neurovascular changes with time in the affected cerebral hemisphere corresponding to aura symptoms during the acute phase of HMPA. Arterial spin labelling MRI, SPECT for CBF measurement and EEG in three attacks, in one attack FDG-PET measurement for cerebral metabolism was performed. We evaluated CBF at different phases of aura symptoms in 11 attacks of HMPA.

RESULTS

In two attacks, we found biphasic CBF changes beginning with hypoperfusion followed by persistent hyperperfusion. FDG-PET revealed increased cerebral glucose metabolism in the regions corresponding to hyperperfusion on day 4 when aura symptoms still persisted. In four attacks, Z-score-based CBF mapping revealed multifocal hypoperfusion in the early phase. Hypoperfusion in our study was seen within 19 h of the onset of the symptoms in five of seven attacks, while hyperperfusion was seen 18 h or later in eight of nine attacks. EEG showed attenuated alpha activity without paroxysmal discharge.

CONCLUSIONS

This is the first report showing biphasic CBF changes during the prolonged aura of FHM2. This study suggested that the results of cross-sectional CBF studies should be interpreted carefully. Initial multifocal hypoperfusion is likely due to functional depression of multifocal origin in the affected hemisphere, but the mechanism of persistent hyperperfusion requires further investigation.

The evolution of a migraine attack - a review of recent evidence

A migraine attack is an extraordinarily complex brain event that takes place over hours to days. This review focuses on recent human studies that shed light on the evolution of a migraine attack. It begins with a constellation of premonitory symptoms that are associated with activation of the hypothalamus and may involve the neurotransmitter dopamine. Even in the premonitory phase, patients experience sensitivity to sensory stimuli, indicating that central sensitization is a primary phenomenon. The migraine attack progresses to a phase that in some patients includes aura, which involves changes in cortical function, blood flow, and neurovascular coupling. The aura phase overlaps with the headache phase, which is associated with further changes in blood flow and function of the brainstem, thalamus, hypothalamus, and cortex. Serotonin receptors, nitric oxide, calcitonin gene-related peptide, pituitary adenylate cyclase-activating polypeptide, and prostanoids are demonstrated specific chemical mediators of migraine based on therapeutic and triggered migraine studies. A number of migraine symptoms persist beyond resolution of headache into a postdromal phase, accompanied by persistent blood flow changes in several brain regions. Although these phases of migraine have substantial temporal, neurochemical, and anatomical overlap, each represents an important window onto the pathophysiology of migraine as well as a target for therapeutic intervention. A comprehensive approach to migraine requires an understanding of the entire range of mechanisms and resultant symptoms that occur throughout the evolution of an attack.

Sporadic hemiplegic migraine presenting as acute encephalopathy

A 10-year-old boy with psychomotor developmental delay and cerebellar vermis atrophy developed right hemiplegia with vomiting, unconsciousness, convulsions, and late-onset fever. Slow delta activity was noted over the left hemisphere on electroencephalography, and neuroimaging revealed swelling of the left temporo-occipital cerebral cortex with restricted diffusivity, successive transient cortical atrophy, and hyperperfusion over the left cerebral hemisphere. Interleukin-6 was elevated in the cerebrospinal fluid. The acute symptoms resolved completely within 3 weeks after onset, but hypoperfusion persisted in the left posterior cortex thereafter. Another episode with transient left hemiplegia appeared 7 months later, followed by recurrence of migraine attacks. Analysis of the CACNA1A gene revealed a mutation of c.1997 C>T (p.T666M). None of his family members had migraine. This case represents an unusual evolution of sporadic hemiplegic migraine with manifestations of acute encephalopathy, for which the role of migraine-related inflammatory process is assumed.