Abstract：Objective: To evaluate the imaging features of pigmented villonodular synovitis(PVNS), and improve imaging diagnostic ability of the disease. Methods: The imaging findings of 12 cases with PVNS confirmed by operation and pathology were analyzed retrospectively. Plain film was performed in 9, CT in 4, MRI in 5. Results: There were totally 12 lesions. Swelling of joint was seen in all patients, and 3 cases with calcifications. In total 12 patients, joint space was normal in 7 cases, widened in 1 case, narrow in 4 cases; and bone erosion was seen in 5 patients, the sclerotic margins were presented in all lesions. CT scan showed diffuse form and joint effusion in all of the 4 patients. MRI in 5 patients showed diffuse form(4 cases) and localized form(1 case); in diffuse form of PVNS, joint effusion was present, and low signal proliferated synovium in all of the patients; in localized form of PVNS in 1 patient, the single mass with joint effusion occurred. Conclusion: The MRI findings of PVNS is characteristic, which is of specific value in the diagnosis and differential diagnosis. Calcifications should not be taken as a denial of PVNS.
2007, Vol. 18 
