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IMAGING OF ANKYLOSING SPONDYLITIS

Ankylosing spondylitis is among HLA-B27-associated diseases. Four common diseases of the HLA-B27- associated group include ankylosing spondylitis, inflammatory bowel disease, psoriatic arthritis and reactive arthritis. This group is characterized by ankylosis, new bone formation and is common in large joints. Ankylosing spondylitis often have bilaterally asymmetrical sacroiliac joint involvement. Diagnosis is based on clinical, HLA-B27 testing and imaging. Conventional radiography is the classic diagnostic criteria. Magnetic resonance has recently been included in the 2009 ASAS diagnostic criteria for early diagnosis.