Response to Letter Regarding Article, “High-Resolution Magnetic Resonance Wall Imaging Findings of Moyamoya Disease”

We appreciate the constructive comments Shang et al1 provided on our report in Stroke ,2 which evaluated high-resolution wall MRI (HR-MRI) findings of Moyamoya disease (MMD) compared with intracranial atherosclerotic disease. MMD exhibited distinct HR-MRI findings, concentric enhancement on bilateral distal internal carotid arteries, and shrinkage of middle cerebral artery, regardless of symptoms (presence or severity) or stage (Suzuki grade).As Shang et al pointed out, the wall enhancement observed in our patients may have been because of luminal (and not wall) enhancement from slow-moving blood adjacent to the wall of the vessel (slow flow artifact). The suppression of intravascular signals is important in vessel wall imaging and various black-blood imaging techniques are used to achieve this, including spatial presaturation (commonly used with T1 fluid-attenuated inversion recovery or volumetric isotropic turbo spin-echo acquisition) and double inversion …