Moyamoya disease in pregnancy: a single institute experience

Moyamoya disease is a rare chronic, occlusive cerebrovascular disease characterized by bilateral steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network at the base of the brain. Moyamoya disease particularly affects children and young adults with female predominance, thus pregnant patients with moyamoya disease are not uncommon. Among 4,400 patients with consecutive deliveries in our hospital, 6 patients (0.14%) aged from 24 to 40 years (mean 32.7 years) were found to have moyamoya disease, all of whom underwent cesarean section. Four patients who had been diagnosed with moyamoya disease before pregnancy did not show neurological events in pregnancy and puerperium, but two patients who were newly diagnosed or progressed during the perinatal period suffered neurological deterioration due to ischemic stroke. Surgical revascularization at the subacute stage relieved their symptoms and they did not suffer permanent neurological deficit. We recommend that pregnant patients with moyamoya disease should be carefully managed under the collaboration of obstetricians and neurosurgeons, and that the procedure of the delivery should selected by the obstetricians to avoid unfavorable sequelae caused by hyperventilation and/or blood pressure elevation.