Imaging of Moyamoya Disease and Moyamoya Syndrome: Current Status

Abstract

Moyamoya disease (MMD) and Moyamoya syndrome (MMS) are referring to a progressive steno-occlusive vasculopathy at terminal portions of the bilateral internal carotid arteries and their proximal branches with prominent collateral artery formation. They can be found throughout the world and cause irreversible damage to the cerebral hemodynamics due to the progressive nature. Prompt diagnosis and accurate assessment could significantly improve the prognosis of MMD and MMS. Some imaging modalities could be used for diagnosis and nonquantitative evaluation of MMD and MMS, such as conventional computed tomography (CT) and magnetic resonance imaging (MRI), digital subtraction angiography, CT angiography (CTA), and magnetic resonance angiography. Some could quantitatively evaluate the cerebral hemodynamics of MMD and MMS, such as single-photon emission CT, positron emission tomography, xenon-enhanced CT, perfusion CT, dynamic susceptibility contrast MRI, arterial spin labeling MRI, and the hemodynamic parameters measured by those imaging methods could guide treatment of MMD and MMS. All the imaging modalities have their merits and demerits, and they can play a part in certain situation. We need establish standardized protocols for preoperative and postoperative evaluation with different imaging techniques in the further science for MMD and MMS.

FIGURE 1

Internal carotid artery angiography shows smog-like vessels. Figure 1 can be viewed online in color at www.jcat.org.

FIGURE 2

Maximal intensity projection images of CTA and bilateral ICA occlusion of the bed segment occlusion. A, Maximal intensity projection images of CTA showed bilateral ICA bed segment occlusion. There was no development of bilateral anterior and middle cerebral arteries, as well as multiple abnormal vascular network at basis crania. B, Magnetic resonance angiography images of bilateral ICA occlusion of the bed segment occlusion. Bilateral middle cerebral artery showed no development. Multiple abnormal vascular network at basis crania.

FIGURE 3

T1-weighted imaging–enhanced scan and FLAIR sequence at basis crania. A, T1-weighted imaging–enhanced display of multiple abnormally enhanced vascular network at basis crania. B, FLAIR sequence bilateral radial coronary region multiple cerebral infarction.

FIGURE 4

FLAIR sequence and T1WI-enhanced scan. A, FLAIR sequence showed multiple dots and bars of high signals (arrows) along the soft meninges distributed in the cerebral cortex of both hemispheres, ivy-like. B, T1-weighted imaging–enhanced scan was performed on both hemispheres of the brain with abnormal enhancement of blood vessels, ivy-like.

FIGURE 5

Basic changes of cerebral hemodynamics in MMD and MMS. Abbreviation: MTT, mean transit time.