Post-gadoliniun enhancement(PGE) in ICAD may be related to endothelial dysfunction or breakdown or secondary to plaque inflammation. Delayed ferumoxytol imaging allows intravascular clearance with retention in the macrophages present in vulnerable atherosclerotic plaque. A 3D BB ME T2* Imaging technique allows the quantitative ferumoxytol imaging on delayed scans by measuring T2* in intracranial atherosclerotic plaque. We performed 3D BB T2* sequences on ten patients with ICAD and measured T2* changes between baseline and 72 hour after ferumoxytol injection. The iron nanoparticle uptake in symptomatic ICAD presented in this work may provide important mechanistic implications for the pathophysiology of PGE.