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Microemboli may link spreading depression, migraine aura, and patent foramen ovale

Ala Nozari1, Ergin Dilekoz, Inna Sukhotinsky

  • 1Stroke and Neurovascular Regulation Laboratory, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA.

Annals of Neurology
|March 13, 2010
PubMed
Abstract

Insights

Microemboli can trigger cortical spreading depression (CSD), a key factor in migraine aura, without causing strokes. This finding suggests a link between paradoxical embolization from shunts and migraine aura, potentially classifying some auras as hypoperfusion disorders.

Area of Science:

  • Neurology
  • Cardiology
  • Vascular Biology

Background:

  • Patent foramen ovale and pulmonary arteriovenous shunts are linked to serious neurological complications, including stroke and migraine with aura.
  • The underlying pathophysiological mechanisms connecting these conditions remain unclear.
  • Understanding this link is crucial for developing targeted therapies.

Purpose of the Study:

  • To investigate the potential mechanism linking microembolization to migraine aura.
  • To establish an experimental animal model to study this relationship.
  • To determine if transient microvascular occlusion can trigger cortical spreading depression (CSD).

Main Methods:

  • Particulate or air microemboli were introduced into the carotid circulation of mice.
  • The study assessed whether microemboli triggered CSD without causing infarction.
  • Histological analysis and magnetic resonance imaging were used to evaluate brain injury.

Main Results:

  • Air microemboli consistently triggered CSD without inducing infarction.
  • Polystyrene microspheres and cholesterol crystals also triggered CSD in a significant portion of mice, often without detectable infarcts or inflammation.
  • Magnetic resonance imaging revealed no injury in most examined animals, indicating CSD can occur without sustained tissue damage.

Conclusions:

  • Microemboli can trigger CSD in a mouse model, frequently without causing microinfarction.
  • This suggests paradoxical embolization may link right-to-left shunts to migraine aura.
  • Migraine auras may represent a spectrum of hypoperfusion disorders, alongside transient ischemic attacks and silent infarcts.

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