Parto Teb Azma

History (HX):
Pain and swelling of the right elbow and right ankle / clinical history of hemophilia, Male 13 yr

Findings:
-Hemosiderin deposing in synovial membrane around these joints low signal on both T1W and T2WI
-Subchondral and intraosseous cysts. Most of them high signal on T2WI and low signal on T1WI compatible with nonhemorrhagic fluid and some are low signal on both T1WI and T2WI representing fibrotic tissue and hemosiderin
-Small cortical erosions

Diagnostic (DX):
Hemophilic arthropathy

Discussion:
The differential diagnosis of synovial-based lesions hypointense on T2WI includes PVNS, GCT  of tendon sheath, synovial chondromatosis, hemophilic arthropathy, amyloid , longstanding RA and siderotic synovitis