Ultrasound (US) Imaging Inflammatory Joint Diseases
My work primarily investigates the role of US imaging in the management of patients with inflammatory joint diseases. Using high frequency transducers we are able to non-invasively study synovium, tendons and ligaments which are primary targets of many of these important diseases. Additionally, US can identify subsequent bone damage which may result from untreated inflammation.
Our preliminary work focussed on the validation of the tool including reliability and validity (primarily comparing it with MRI and histological specimens obtained from arthroscopy). We have confirmed that US is both a reliable and valid tool for the assessment of inflammatory joint pathology. This work has led to the development of internationally agreed standardised pathological US definitions through the EULAR and OMERACT Task Forces.
We have subsequently demonstrated that US is more sensitive than our current standards of clinical examination and radiography for detecting synovitis, tendon disease and bone damage and have recommended its use in routine clinical practice. Images 1 and 2 demonstrate the presence of synovitis in a clinically non swollen joint using US and MRI. This acknowledgment of sub-clinical disease has enabled us to propose a re-classification of oligo-articular diseases based on imaging (Wakefield et al. Should oligoarthritis be reclassified? Ultrasound reveals a high prevalence of subclinical disease. ARD 2004;63:382-5), provide an earlier diagnosis of polyarticular diseases like RA and optimise disease suppression. A recent study showed that despite the establishment of clinical remission post anti-TNF therapy, disease activity remains on US.
Areas of work currently under investigation include: 1) the role of US as a prognostic marker; 2) the role of US in the longitudinal evaluation of joint diseases; and 3) the role of US as a treatment endpoint.
Figure 1 Ultrasound: Longitudinal, dorsal image through the index metacarpo-phalangeal joint of a patient with RA. Clinically, there was joint tenderness only but no evidence of swelling. There is grey scale synovitis (white arrows) with internal power Doppler signal indicating here a moderate degree of vascularitiy. MC=metacarpal, P= phalanx
Figure 2 MRI: Axial section through MCPJ of same patient. There is synovitis which is enhancing with i.v .contrast agent gadolinium.
Wakefield RJ, O’Connor PJ, Conaghan PG, McGonagle D, Gibbon W Brown C, Emery P. Finger tendon disease in untreated early RA: A comparison of ultrasound and magnetic resonance imaging, Arthritis Rheum 2007 Oct 15;57(7):1158-64.
Wakefield RJ, D’Agostino MA, Iagnocco A, Filippucci E, Backhaus M, Scheel AK, Joshua F, Naredo E, Schmidt WA, Grassi W, Moller I, Pineda C, Klauser A, Szkudlarek M, Terslev L, Balint P, Bruyn GA, Swen WA, Jousse-Joulin S, Kane D, Koski JM, O’connor P, Milutinovic S, Conaghan PG. The OMERACT Ultrasound Group: Status of Current Activities and Research Directions. J Rheumatol. 2007;34:848-51.
Wakefield RJ, Freeston J, Hensor EA, Bryer D, Emery P. Delay in Imaging versus Clinical Response Provides a Rationale for Prolonged Treatment with Anti-TNF Medication in Early Rheumatoid Arthritis Rheum 2007 Nov 29;57(8):1564-1567