Keywords: rheumatoid arthritis, high-resolution CT, imaging, bone, bone density, bone microstructure

“High resolution CT imaging of finger joints: Automation of cortical interruption detection”

Rheumatoid arthritis is a chronic disease characterised by inflammation of the joints causing bone destruction of, for instance, the finger joints. High-resolution peripheral quantitative computed tomography (HR-pQCT) is a new technology allowing the assessment of bone microstructure and bone density and consequently the detection of minor damage (i.e. cortical disruptions). Up to now, cortical disruptions found on HR-pQCT images have been visually scored, which is a rather unreliable, time-consuming method. This dissertation shows the development of a computer algorithm allowing reliable detection of minor cortical disruptions of the finger joints. We found that patients with rheumatoid arthritis had more cortical disruptions and a lower bone density. In summary, this dissertation shows that HR-pQCT combined with our algorithm has great potential for the evaluation of (early) bone damage of the finger joints in patients with rheumatoid arthritis. This method can be a useful addition to the currently available imaging techniques, not only in terms of detecting cortical disruptions but also in terms of quantifying bone density and bone microstructure.