Silent or non-clinical infarct-like lesions in the posterior circulation territory in migraine: brain hypoperfusion or hyperperfusion?

White matter lesions progression in migraine with aura: a clinical and MRI longitudinal study

OBJECTIVE

To prospectively evaluate longitudinal changes in white matter lesions (WMLs) in migraineurs with aura, by magnetic resonance imaging (MRI), and to correlate WMLs modifications with patients' clinical characteristics.

METHODS

Forty-one consecutive migraineurs with aura were followed for a mean time of 33.2 months. Patients underwent MRI at baseline and follow-up and were evaluated for cerebrovascular risk factors. Presence of WMLs on MRI was assessed by two neuroradiologists.

RESULTS

WMLs were present in 26 subjects (63.4%) at baseline MRI. At follow-up a total of 8 patients had new WMLs (19.5%). There was a significant correlation between aura duration and number of new WMLs, and between the number of migraine attacks with aura and new WMLs.

CONCLUSIONS

Our study demonstrates that in migraine with aura WMLs number can progress over time and suggests an association between aura features and WMLs progression. Studies with a higher number of patients are required to confirm these findings.

Risk of "silent stroke" in patients older than 60 years: risk assessment and clinical perspectives

With the increasing size of the elderly population and evolving imaging technology, silent brain infarction (SBI) has garnered attention from both the public and the physicians. Over 20% of the elderly exhibit SBI, and the prevalence of SBI increases steadily with age, ie, 30%–40% in those older than 70 years. Well-known cardiovascular risk factors such as hypertension has been identified as a risk factor of SBI (odds ratio [OR] = 3.47) Besides this, blood pressure (BP) reactivity to mental stress, morning BP surges, and orthostatic BP changes have been demonstrated to contribute to the presence of SBI. Further, a metabolic syndrome not only as a whole syndrome (OR =2.18) but also as individual components could have an influence on SBI. Increased C-reactive protein and interleukin-6, coronary artery disease, body mass index, and alcohol consumption have also been associated with SBI. The ORs and possible mechanisms have been discussed in this article. Overt stroke, dementia, depression, and aspiration pneumonia were all associated with SBI. (overt stroke: hazard ratio [HR] =1.9, 95% confidence interval [CI]: 1.2–2.8; dementia: HR =2.26, 95% CI: 1.09–4.70). We also looked into their close relationship with SBI in this review.

Migraine and stroke: current perspectives

OBJECTIVE

The purpose of this article is to review the latest concepts regarding migraine and ischemic stroke. In addition, focal neurological deficits and MRI changes in migraine patients will be reviewed.

METHODS

A PubMed search of neurological literature pertaining to this study was conducted using specific keyword search terms pertaining to migraine and ischemic stroke.

RESULTS

Migraine, especially with aura, is a relative risk factor for stroke. Neuroimaging demonstrates the posterior circulation as being most vulnerable, although the reason for this distribution is unclear. Factors that may contribute to stroke in migraine include changes during cortical spreading depression with hyper- or hypoperfusion of neural tissue, vasospasm and endothelial dysfunction. Estrogen affects migraine expression as well as cerebral circulation, yet most women with migraine without aura are not at increased risk. Co-morbidity with patent foramen ovale can be mechanism of both disorders via presumed lack of filtration of microemboli or toxic substances; however, closure with reversal of right to left shunt seems to be more beneficial for cryptogenic stroke than migraine. Migraine and stroke are found in specific genetic disorders such as CADASIL, HERNS and MELAS giving clues to genetic factors. Stroke associated with migraine treatments such as ergots or triptans is rare, and usually associated with special circumstances such as overuse or concomitant thrombogenic conditions.

CONCLUSION

Although true migrainous infarction is rare, our understanding of the subtle associations between migraine and cerebrovascular behavior is expanding.

Arterial spin-labeling in routine clinical practice, part 3: hyperperfusion patterns

Arterial spin-labeled (ASL) perfusion imaging can be implemented successfully into a routine clinical neuroimaging protocol and can accurately demonstrate alterations in brain perfusion. We have observed patterns of focal, regional, and global hyperperfusion in a wide variety of disease processes. The causes of hyperperfusion at clinical ASL have not been previously characterized. Focal lesions such as brain tumors and vascular malformations with increased perfusion can be well depicted by ASL. More global causes of hyperperfusion, including postanoxia vasodilation and hypercapnia, may go undetected on conventional MR images, whereas the regional hyperperfusion, which may occur in reversible encephalopathies and luxury perfusion, has been consistently illustrated on ASL cerebral blood flow maps at our institution.

White Matter Lesions in Migraine and Right-to-Left Shunt: A Conventional and Diffusion MRI Study

Subjects with migraine with aura (MA) have a high prevalence of white matter lesions (WMLs) on magnetic resonance imaging (MRI). Moreover, right-to-left shunt (RILES), mainly due to patent foramen ovale, is frequently associated with MA. The aim of this study was to clarify the relationship between RILES and WML in MA. We enrolled 87 consecutive subjects affected by MA. Patients were screened for migraine characteristics and cerebrovascular risk factors. Transcranial Doppler was used to diagnose RILES and MRI with T2-weighted and diffusion-weighted imaging (DWI) to evaluate presence, number and volume of WMLs. RILES was present in 45% of patients. We did not detect any DWI hyperintense lesion; WMLs were present in 61% of patients on T2-weighted images. Presence of WMLs did not correlate with any migraine clinical feature, whereas the presence, number and volume of WMLs increased with subjects' age. There was no significant difference in the total volume and number of WMLs in the group with and without RILES. In conclusion, RILES does not increase the likelihood of finding WMLs in migraineurs.