1. From the Department of Radiology, Queen Mary Hospital, 102 Pokfulam Rd, Hong Kong, HKSAR (K.H.L., V.W.H.L.); Division of Rheumatology and Clinical Immunology, Department of Medicine (H.Y.C., C.S.L.), and Department of Diagnostic Radiology (X.X.), University of Hong Kong, Pokfulam, Hong Kong, HKSAR.