The Relationship Between Right-to-left Shunt and Brain White Matter Lesions in Patients With Migraine

Inclusion Criteria: * patients who fulfilled the criteria for migraine according to the International Classification of Headache Disorders III-beta were included. healthy volunteers without a history of migraine were included as controls. Exclusion Criteria: * Subjects were excluded from the study if they had severe arterial stenosis, an insufficient temporal window, inadequate cubital venous access, and/or were unable to perform the Valsalva manoeuvre (VM) because of severe heart or lung disease.