Purpose  Rheumatoid arthritis (RA) is a disease characterized by progressive and irreversible destruction of bones and joints. According to current recommendations, magnetic resonance imaging (MRI) is used to asses three main signs of RA based on manual evaluation of MR images: synovitis, bone edema and bone erosions. The key feature of a future computer-assisted diagnostic system for evaluation RA lesions is accurate segmentation of 15 wrist bones. In the present paper, we focus on developing a wrist bones segmentation framework.Method   The segmentation procedure consisted of three stages: segmentation of the distal parts of ulna and radius, segmentation of the proximal parts of metacarpal bones and segmentation of carpal bones. At every stage, markers of bones were determined first, using an atlas-based approach. Then, given markers of bones and a marker of background, a watershed from markers algorithm was applied to find the final segmentation.Results  The MR data for 37 cases were analyzed. The automated segmentation results were compared with gold-standard manual segmentations using a few well-established metrics: area under ROC curve AUC, mean similarity MS and mean absolute distance MAD. The mean (standard deviation) values of AUC, MS and MAD were 0.97 (0.04), 0.93 (0.09) and 1.23 (0.28), respectively.Conclusion  The results of the present study demonstrate that automated segmentation of wrist bones is feasible. The proposed algorithm can be the first stage for the detection of early lesions like bone edema or synovitis.

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This paper probes the distinction between the so-called emotional support animals (ESAs), a term that is specific to the USA and that has recently been the subject of significant media attention, and service animals. The attention devoted to ESAs has largely taken on the form of jokes and critical comments related to the absurdity of the ‘political correctness’ that makes it possible for pigs to fly in the passenger cabin of airplanes and llamas to accompany their owners on trips to the supermarket. Much criticism is meted out, also from within the disability community, against animal guardians who try to ‘pass their animals off’ as service dogs and ESAs, with a call for the establishment of clear-cut criteria for the definition of ESAs and service animals. The paper’s methodology is an analysis of the media accounts of legitimate and illegitimate service animals; an analysis that reveals how the boundary between legitimate and illegitimate is constructed through the building blocks of these stories. ESAs are something of a limit case that points to the cultural paradoxes that govern Americans’ relationships with companion animals and with concepts of disability. The paper also argues that the insistence on establishing firm boundaries between ‘legitimate’ service animals and ESAs actually fosters a politics of suspicion, which can easily slip into suspicion directed at the human handlers of the animals.

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