Case of de novo cerebral microbleeds in ischemic-type pediatric moyamoya disease

Studies on pediatric patients with moyamoya disease who presented with cerebral microbleeds (CMBs) are extremely rare. Herein, we report a 7-year-old boy with moyamoya disease who had CMBs during treatment. He presented with transient left-side motor weakness and was diagnosed with moyamoya disease. He underwent revascularization surgery on the right cerebral hemisphere. Six months after the surgery, he presented with transient right-side motor weakness and MRA revealed progression of stenosis in the left middle cerebral artery. After another 3 months, three CMBs were identified. He underwent revascularization surgery on the left side. The symptom disappeared completely after surgery and no additional CMBs were identified 1 year after surgery. This is the first report on CMBs in pediatric patients. Although the significance of CMBs in pediatric patients is completely unknown, attention should be paid to not only ischemic stroke but also hemorrhagic stroke. Although the short-term course is good in the current case, follow-up period is too short to assess for rebleeding and long-term follow-up is still important. Further, more cases should be collected.