Multimodality Imaging of Moyamoya Disease: A Practical Guide for Neuroradiologists Based on a Case Report

<b>Background and Clinical Significance</b>: Moyamoya disease is a rare, progressive cerebrovascular disease characterized by steno-occlusion of the terminal internal carotid arteries and the arteries around the circle of Willis, with the formation of abnormal collateral vessels. Early clinical manifestations include recurrent hemodynamic transient ischemic attacks (TIAs), especially in young subjects. Multimodality imaging, including computed tomography, magnetic resonance, and digital subtraction angiography, is necessary to reach a correct diagnosis in young patients with stroke-like symptoms. Various radiological findings are crucial for early diagnosis, staging, and management of moyamoya disease. <b>Case Presentation</b>: We describe the case of a 31-year-old male presenting with acute focal neurological deficits and a history of recurrent TIAs. Neuroimaging was performed to assess vascular pathology, parenchymal injury, and collateral circulation and to provide critical information on vascular anatomy and the extent of ischemic damage. <b>Conclusions</b>: The purpose of this case report is to illustrate the main specific radiological signs and the diagnostic value of multimodality neuroimaging in the evaluation of moyamoya disease, providing a practical imaging-based diagnostic approach for neuroradiologists.