What is the likelihood of migraine patients developing multiple periventricular and juxtacortical lesions simultaneously?

Likelihood of Migraine Patients Showing Multiple Periventricular and Juxtacortical Lesions Simultaneously

Migraine patients have a relatively low likelihood of presenting with multiple periventricular AND juxtacortical lesions simultaneously, as this pattern is more characteristic of multiple sclerosis than migraine. 1, 2

Periventricular Lesions in Migraine

• Up to 30% of migraine patients may have periventricular lesions 1, 2
• However, these lesions typically have distinct characteristics compared to MS lesions:
  • Usually small, punctate hyperintensities 2, 3
  • Often do not directly abut the ventricles 2
  • Lack the "Dawson's fingers" appearance (ovoid shape perpendicular to ventricles) 1, 2
  • Rarely present as multiple (≥3) lesions directly touching the ventricles 1, 2

Juxtacortical Lesions in Migraine

• Juxtacortical lesions can occur in migraine patients 2, 4
• In one study, juxtacortical spots on FLAIR images were found in 55.1% of migraine patients compared to 22.2% of healthy controls 4
• Migraine-related juxtacortical lesions:
  • Are typically separated from the cortex by a rim of normal white matter 2
  • Often appear as small, punctate hyperintensities 3
  • May be associated with right-to-left shunts in migraine patients 4

Distinguishing Features from MS Lesions

When both periventricular AND juxtacortical lesions are present simultaneously, consider these distinguishing features:

1. Number and location:

   • MS typically shows ≥3 periventricular lesions 1
   • MS lesions commonly involve the corpus callosum, infratentorial regions, and spinal cord 1, 2

2. Morphology:

   • MS periventricular lesions are ovoid and perpendicular to ventricles (Dawson's fingers) 1
   • MS juxtacortical lesions directly abut the cortex 1, 2
   • Migraine lesions are typically small and punctate 2, 3

3. Distribution pattern:

   • The simultaneous presence of multiple periventricular AND juxtacortical lesions is more suggestive of MS than migraine 1, 2
   • Migraine patients more commonly have deep white matter lesions 2, 5

Risk Factors for White Matter Lesions in Migraine

• Female sex 5, 4
• Migraine with aura 1, 5
• Higher attack frequency (≥1 attack per month) 5
• Presence of right-to-left cardiac shunts 6, 4

Pathophysiological Mechanisms

• Cortical spreading depolarization in migraine may cause oligemia leading to ischemic/hypoxic changes at watershed areas 7
• Endothelial dysfunction, hypercoagulability, and platelet aggregation may contribute to white matter lesions 6
• Women with migraine with aura have an increased risk for late-life ischemic lesions on brain MRI 1

Clinical Implications

• When multiple periventricular AND juxtacortical lesions are found simultaneously in a migraine patient, consider:

  1. Possibility of comorbid MS (especially with ≥3 periventricular lesions with Dawson's fingers appearance) 1
  2. CADASIL if lesions involve the anterior temporal pole, external capsule, basal ganglia, and/or pons 2, 3
  3. Other vascular or inflammatory conditions 1, 2

• The MAGNIMS consensus guidelines recommend using ≥3 periventricular lesions (not just 1) as a criterion for MS diagnosis to improve specificity 1

In summary, while migraine patients can have both periventricular and juxtacortical lesions, the simultaneous presence of multiple lesions in both locations with MS-like characteristics (Dawson's fingers, direct abutment to ventricles/cortex) is uncommon in migraine and should prompt consideration of alternative diagnoses.