Prediction of Intracranial Arterial Stenosis Progression in Patients with Moyamoya Vasculopathy: Contrast-Enhanced High-Resolution Magnetic Resonance Vessel Wall Imaging.

OBJECTIVE: Moyamoya vasculopathy (MMV) is characterized by progressive stenosis of the intracranial arteries. MMV currently has no curative treatments, and cerebral ischemia and hemorrhage are the major outcomes. Evaluation of the stroke risk of each patient resulting from the progression of intracranial arterial stenosis is clinically important.
METHODS: We prospectively reviewed patients with intracranial arterial stenosis and already diagnosed MMV. High-resolution magnetic resonance imaging using contrast agent is the novel vessel wall imaging (VWI) technique for directly evaluating vascular walls and intracranial artery disease. All patients underwent high-resolution vessel wall imaging and magnetic resonance angiography at the time of registration, and they underwent follow-up magnetic resonance angiography. The Fisher exact test was used to assess associations between the degrees of wall enhancement and between stable and progressive intracranial arterial stenosis.
RESULTS: A total of 24 patients (17 female; mean age, 36.1 ± 16.8 years; range 3-67 years) with MMV were consecutively recruited to this study. Progression of stenosis was shown in 6 lesions (66.6%) on strong enhancement, 2 lesions (12.5%) on mild enhancement, and 1 lesion (4.3%) on lack of enhancement. Arterial vessel wall enhancement in MMV patients correlated closely with progression of intracranial arterial stenosis (P = 0.002).
CONCLUSIONS: Arterial vessel wall enhancement in MMV patients was closely related to progression of intracranial arterial stenosis. Strong enhancement of the intracranial vessel wall was associated with intracranial arterial stenosis progression, and lack of enhancement correlated with the stability of intracranial arterial stenosis.