Synovial haemangioma diagnosed during knee arthro-CT.

Synovial haemangiomas are uncommon lesions most frequently found in the knee. We report a case in the popliteal area fortuitously demonstrated during knee msCT arthrography in a young female. The diagnosis was made possible by the sharp enhancement of the tumor caused by the venous drainage of the contrast medium injected into the synovial cavity. The diagnosis was confirmed by msCT angiography and MRI.