Small Demyelination of the Cortex May Be a Potential Marker for the Right-to-Left Shunt of the Heart

Migraine is a common clinical primary headache with unclear aetiology. In recent years, studies have shown that migraine is related to right-to-left shunts (RLS), and some patients with migraine have white matter lesions. However, the relationship among the three is unclear. To explore the characteristics of white matter lesions (WMLs) in migraine patients with right-to-left shunts and to predict the presence of right-to-left shunts through magnetic resonance imaging (MRI) characteristics in patients with migraine, we conducted a retrospective study. We enrolled 214 patients who were diagnosed with migraines in an outpatient clinic from January 2019 to December 2021. All of them had completed contrast transcranial Doppler ultrasound (cTCD) and magnetic resonance imaging (MRI) examination. Through the inclusion and exclusion criteria, 201 patients were finally included. The patients were grouped according to the presence of WMLs and were compared by age, sex, hypertension, diabetes, RLS, and other characteristic data. We observed the MRI fluid attenuation inversion recovery sequence (FLAIR) image and compared the differences in WMLs between the RLS-positive group and the RLS-negative group. There were 71 cases and 130 cases of migraine with and without WMLs, respectively. A statistically significant difference in near-cortical WMLs with RLS in migraine patients was observed (p = 0.007). Logistic regression analysis was adjusted by age, sex, duration of migraine, and severity. Migraine with aura and family history identified the RLS status as the sole determinant for the presence of near-cortical WMLs (OR = 2.69; 95%CI 1.386–5.219; p = 0.003). Near-cortical white matter lesions in migraine patients are related to RLS, especially in the blood supply area of the anterior cerebral artery. This small demyelination of the near-cortical WMLs may be a potential marker for the right-to-left shunt of the heart. Transcranial Doppler ultrasonography may help finding more RLS in migraineurs with near-cortical WMLs.