1. From the University Department of Radiology (T.T., S.P.S.H., R.T., M.J.G., J.U.K.-I., Z.Y.L., J.H.G.), Cambridge University Hospitals NHS Foundation Trust, Cambridge; Biostatistics and Data Sciences (S.R.M.), GlaxoSmithKline, Harlow; Translational Medicine and Genetics (A.P.B.), GlaxoSmithKline, Greenford; Department of Neurosurgery (S.P.S.H., P.K.), Cambridge University Hospitals NHS Foundation Trust, Cambridge; and the Vascular Unit (T.T., M.E.G.), Cambridge University Hospitals NHS Foundation...