1. From the Departments of Imaging (C.A.R., S.R.D., C.M., D.L.L., S.M., T.S., E.S., S.P.G.P., A.D.), Anaesthesia and Critical Care (S.P., C.B., B.V.P.), and Haematology (D.J.A.), Royal Brompton Hospital, Sydney Street, London SW3 6NP, England; School of Medicine (N.J.), Inflammation & Immunology (D.J.A.), Surgery & Cancer (B.V.P.), and Haematology (D.J.A.), Imperial College London, London, England.