Case report 731

Fig. 3. A Tl-weighted (TR 617/TE 20) axial magnetic resonance (MR) image of the right knee demonstrates a right popliteal mass with central punctate loci of signal void. B T2-weighted (TR 2000/TE 80) axial MR image shows the popliteal mass of increased signal with mixed areas of decreased signal. The central signal voids are unchanged. C T2-weighted (TR 2000/TE 80) sagittal MR image again shows the popliteal mass with heterogeneous signal. The signal voids are again noted on this image (arrows) corresponding to gas bubbles observed on plain film