Synovial hemangioma

Synovial hemangiomas are rare benign vascular malformations that occur in relation to the joint. It is sometimes considered a subtype of soft tissue hemangiomas.

Epidemiology

The lesions typically present in children and young adults. Occasionally patients can have recurrent haemarthroses .

Clinical presentation

Patients may have pain, swelling and/or limited joint mobility.

Pathology

The lesions can be cavernous, capillary or mixed.

Location

Most lesions tend to occur around the knee .

Radiographic features

Plain radiograph

Plain film findings are generally non-specific and may be seen as a soft tissue mass adjacent to the knee. Accompanying phleboliths may be present.

MRI

Typically seen as a lobulated intra-articular mass (although the lesions can be either lobulated or diffuse).

Signal characteristics include:

• T1: usually of intermediate signal
• T2 
  • markedly hyperintense background; likely from pooled blood within vascular spaces
  • low-signal-intensity linear structures within lesion; likely from fibrous septa or vascular channels
  • fluid-fluid levels may be present 
• T1 C+: marked enhancement

Differential diagnosis

Imaging differential considerations include:

• cystic synovial hyperplasia: usually peripheral enhancement only
• synovial chondromatosis
• pigmented villonodular synovitis (PVNS)

Siehe auch:

• synoviale Osteochondromatose
• Pigmentierte villonoduläre Synovialitis
• synoviale Raumforderungen
• proliferations of the synovial membrane
• zystische Synoviahyperplasie
• Hämatom der Synovialmembran

und weiter:

• Hämangiom
• Lipoma arborescens
• siderotic synovitis
• Weichteilhämangiom
• WHO Klassifikation der Weichteiltumoren
• skeletal mass with fluid-fluid levels
• extraskeletal musculoskeletal tumors by compartment
• extra skeletal musculoskeletal lesions by compartment
• Lipoma arborescens Kniegelenk
• Flüssigkeit-Flüssigkeitsspiegel