High-resolution Magnetic Resonance Imaging of Moyamoya Disease

OBJECTIVE: To introduce the imaging characteristics of moyamoya disease (MMD) using high-resolution magnetic resonance imaging (HR-MRI) and to discuss the role of HR-MRI in differentiating MMD from other intracranial artery diseases, especially intracranial atherosclerotic disease (ICAD). DATA SOURCES: This review was based on the data in articles published between 2005 and 2015, which were obtained from PubMed. The keywords included HR-MRI, MMD, ICAD, and intracranial artery diseases. STUDY SELECTION: Articles related to HR-MRI for MMD or other intracranial artery diseases were selected for review. RESULTS: There are differences between the characteristic patterns of HR-MRI in MMD and ICAD. MMD is associated with inward remodeling, smaller outer diameters, concentric occlusive lesions and homogeneous signal intensity, while ICAD is more likely to be associated with outward remodeling, normal outer diameters, eccentric occlusive lesions, and heterogeneous signal intensity. Other intracranial artery diseases, such as dissection and vasculitis, also have distinctive characteristics in HR-MRI. HR-MRI may become a useful tool for the differential diagnosis of MMD in the future. CONCLUSIONS: HR-MRI of MMD provides a more in-depth understanding of MMD, and it is helpful in evaluating pathological changes in the vessel wall and in differentiating MMD from other intracranial artery steno-occlusive diseases, particularly ICAD.