Enhancement of the Ivy Sign during an Ischemic Event in Moyamoya Disease

We herein report a case of increased and expanded ipsilateral ivy sign paralleling the expansion of cerebral infarction in a patient with moyamoya disease. A 67-year-old woman visited our hospital with symptoms of left hemiplegia, left homonymous hemianopia, and left unilateral spatial neglect. Magnetic resonance imaging of the head showed cerebral infarction in the right parietal lobe. In addition, ivy signs were evident on fluid-attenuated inversion recovery imaging. These findings were enhanced by the expansion of cerebral infarction and disappeared once the ischemia resolved, implying hemodynamic changes. As a result of continuing medical treatment without antithrombotic therapy, the patient obtained a good outcome. Treatment for moyamoya disease in the acute phase is considered to require complex knowledge of multiple factors, such as the anatomical background of the individual patient and the progression grade of ischemia.