Vessel Wall Imaging at 7T in Moyamoya arteriopathy
Matthew N DeSalvo1, Loai Aker2, Alfred P See2
1From the Department of Radiology (M.N.D., L.A., D.P.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA and Cerebrovascular Surgery and Interventions Center (A.P.S., J.S.M.), Department of Neurosurgery, Boston Children's Hospital, Boston, MA. mdesalvo@bwh.harvard.edu.
Background:
Ultra-high-field 7 Tesla (7T) vessel wall imaging (VWI) enables high-resolution evaluation of intracranial arterial pathology, but its clinical reproducibility and diagnostic value in moyamoya arteriopathy have not been demonstrated.
Purpose:
To evaluate the technical feasibility and inter-reader reliability of a structured segment-wise 7T VWI framework in moyamoya arteriopathy and to characterize patterns of vessel wall abnormalities.
Methods:
Eighteen patients (12 female, median age 25.4 years, IQR 19.0-26.9) with moyamoya arteriopathy underwent 7T VWI including 0.5 mm isotropic T1-weighted fat saturated pre- and post-contrast SPACE sequences. Twelve arterial segments per patient were assessed for remodeling, wall thickening, and enhancement. Inter-reader reliability between two readers was evaluated using Cohen's kappa. Associations with clinical variables including prior stroke, revascularization status, disease duration, and time since revascularization were analyzed.
Results:
Across 210 analyzable segments, remodeling was present in 72.4%, wall thickening in 65.2%, and enhancement in 15.7%. Inter-reader reliability was high for all features: remodeling (κ = 0.895; 95% CI, 0.827-0.962; 95.7% agreement), thickening (κ = 0.834; 95% CI, 0.755-0.912; 92.4% agreement), and enhancement (κ = 0.763; 95% CI, 0.639-0.888; 93.8% agreement), with overall agreement of 94.0%. Remodeling was strongly associated with thickening (p<0.001) and enhancement (p<0.001), and was the only imaging feature significantly associated with prior stroke (p=0.011). Enhancement demonstrated a significant inverse correlation with time since revascularization (ρ = -0.45, p=0.013), although this was highly collinear with disease duration.
Conclusion:
Segment-wise 7T VWI in moyamoya arteriopathy is technically feasible and demonstrates high inter-reader reproducibility, including in distal small-caliber arteries. This framework enables detailed and reliable characterization of vessel wall abnormalities and may support clinical assessment as well as future studies of disease biology and longitudinal progression.
Related Concept Videos
01:19Imaging Studies VII: Vascular Imaging
01:21Imaging Studies for Cardiovascular System IV: CMRI