Figure 1. (a) T₁ weighted, (b) T₂ weighted and (c) fat suppressed T₂ weighted sagittal images of the left knee, demonstrating joint effusion and a large intra-articular heterogeneous mass with multiple peripheral serpentine signal voids (arrowheads). An area of highsignal intensity on T₁, T₂ and fat suppressed T₂ weighted images represents sub acute haemorrhage (arrows).