Presentation
Knee swelling and chronic pain
Patient Data
MRI typically shows large joint effusion with multiple foci of low signal intensity within the joint space, and extensive mass-like synovial proliferation with low signal intensity on T1-WI and low to intermediate signal on T2-WI and high signal intensity on PD sequences. Multiple osseous erosions are seen.
Case Discussion
Imaging findings are characteristic of recurrence of a pathologically proven pigmented villonodular synovitis (PVNS). PVNS is a rare synovial disorder but the features of this disease on MRI is unique, The characteristic blooming seen on GRE images and low T1 and T2 signal intensity reflect the hemosiderin-laden synovial tissue.
Recurrence is more frequent with diffuse intra-articular PVNS, and adjuvant radiation therapy may be useful.