Page 127 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

monetary costs and radiation dose all fall between conventional radiography and CT. Tomosynthesis is currently used in mammography and research for other applications is ongoing. Recently, the value of tomosynthesis has been evaluated for features of OA and RA in hand joints. When CT was used as the reference standard, the specificity of both tomosynthesis and CR was high, but the sensitivity of tomosynthesis for JSN, osteophytes and erosions was much higher than CR.9-11. One study even concluded that the diagnostical performance of tomosynthesis was comparable to MRI for detection of erosions.12 These studies are very promising and tomosynthesis may therefore find it’s place in future research and clinical work.
Nuclear imaging methods are beyond the scope of this thesis, but may also be very interesting for OA and RA research. They show pathophysiology instead of anatomical details, and can be used in combination with radiological imaging methods. 18-fluoride is a positron emission tomography (PET)-tracer which is sensitive for bone remodeling. It has shown to be present in bone of OA patients at the place of BMLs and adjacent to mild cartilage damage. Future studies may show that 18F is an early marker of OA and predict (sub)chondral bone damage. The upcoming advent of PET-MRI may more easily combine these studies with morphological MRI and MRI measures of cartilage composition.
Conclusions:
• Direct cartilage imaging with high resolution MRI in small hand joints has a higher accuracy than indirect cartilage imaging.
• CT has a better detection rate of OA features in the STT joint than conventional radiography, and may therefore be recommend pre-surgery if this influences the surgical plan.
• Contrast enhanced low field MRI has a high accuracy for detection of early synovitis in the hand, but shows poor diagnostic performance in detection of bone marrow edema.
• Ultrasound has a lower sensitivity than contrast enhanced MRI for detection of early synovitis, but is specific.
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General discussion
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