A new magnetic resonance imaging scoring method for assessment of haemophilic arthropathy

Abstract

In a European multicentre study, 39 ankles in 28 haemophilic boys were investigated by magnetic resonance imaging (MRI). A new MRI score was developed in the format A(e:s:h) for evaluating haemophilic arthropathy. This scheme provides high resolution and allows separation of different pathological components. The factor A is calculated as the sum of scores for subchondral cysts (maximum value 6), irregularity/erosion of subchondral cortex (maximum 4) and chondral destruction (maximum 6); e, s and h, respectively, represent effusion/haemarthrosis, synovial hypertrophy and haemosiderin deposition, and they are separately evaluated on a scale of 0-4. Working independently, two radiologists scored the 39 ankles twice using both this new 'European' scoring method and a previously published 'Denver' scoring scheme. Final classification was achieved by consensus. The reproducibility of the readings was assessed, and for both scoring methods the results indicated good or moderate intraobserver agreement, and good, moderate or fair interobserver agreement. These findings suggest that MRI can be useful for semiquantitative evaluation of haemophilic arthropathy, providing the examination is performed according to an appropriate protocol, and the images are evaluated by specially trained radiologists.