Imaging in psoriasis and psoriatic arthritis: GRAPPA 2008.

At the 2008 meeting of GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis), the primary focus of the imaging session was the enthesis. Presentations from Dennis McGonagle (Leeds, UK), Richard Hodgson (Leeds, UK), and Paolo Gisondi (Verona, Italy) elaborated on this theme and prepared the meeting attendees for group discussions of further work in this area. Imaging, notably magnetic resonance imaging (MRI) and ultrasonography, provides evidence of pathological change at the enthesis in psoriatic arthritis (PsA). Further, imaging abnormalities are found at sites that are asymptomatic in both PsA and psoriasis. The role of newer imaging modalities, such as ultra-short echo time (UTE) MRI, is promising but remains to be fully elucidated. The implication of these findings in relation to subclinical and predisease status is intriguing and requires further study in longitudinal studies. Further work is also required to examine the proposed common biomechanical basis between joint and skin, the mechanism of the resulting inflammation, and how these mechanisms differ from those seen in rheumatoid arthritis.