The WORMS method described in this report provides multi-feature, whole-organ assessment of the knee in OA using conventional MR images, and shows high inter-observer agreement among trained readers. This method may be useful in epidemiological studies and clinical trials of OA.

Summary Objectives To report on the process and criteria for selecting acquisition protocols to include in the osteoarthritis initiative (OAI) magnetic resonance imaging (MRI) study protocol for the knee. Methods Candidate knee MR acquisition protocols identified from the literature were first optimized at 3 Tesla (T). Twelve knees from 10 subjects were scanned one time with each of 16 acquisitions considered most likely to achieve the study goals and having the best optimization results. The resultant images and multi-planar reformats were evaluated for artifacts and structural discrimination of articular cartilage at the cartilage–fluid, cartilage–fat, cartilage–capsule, cartilage–meniscus and cartilage–cartilage interfaces. Results The five acquisitions comprising the final OAI MRI protocol were assembled based on the study goals for the imaging protocol, the image evaluation results and the need to image both knees within a 75 min time slot, including positioning. For quantitative cartilage morphometry, fat-suppressed, 3D dual-echo in steady state (DESS) acquisitions appear to provide the best universal cartilage discrimination. Conclusions The OAI knee MRI protocol provides imaging data on multiple articular structures and features relevant to knee OA that will support a broad range of existing and anticipated measurement methods while balancing requirements for high image quality and consistency against the practical considerations of a large multi-center cohort study. Strengths of the final knee MRI protocol include cartilage quantification capabilities in three planes due to multi-planar reconstruction of a thin slice, high spatial resolution 3D DESS acquisition and the multiple, non-fat-suppressed image contrasts measured during the T2 relaxation time mapping acquisition.

Objective. Achieving remission is the aim of treatment in rheumatoid arthritis (RA). This should represent minimal arthritis activity and ensure optimal disease outcome. However, we have previously demonstrated a high prevalence of imaging-detected synovial inflammation in RA patients who were in clinical remission. The purpose of this study was to evaluate the long-term significance of subclinical synovitis and its relationship to structural outcome.Methods. We studied 102 RA patients receiving conventional treatment who had been judged by their consultant rheumatologist to be in remission, as well as 17 normal control subjects. Subjects underwent clinical, laboratory, functional, and quality of life assessments over 12 months. In addition to standard radiography of the hands and feet, imaging of the hands and wrists was performed with musculoskeletal ultrasonography (US) and conventional 1.5T magnetic resonance imaging (MRI) at baseline and 12 months, using validated acquisition and scoring techniques.Results. Despite their being in clinical remission, 19% of the patients displayed deterioration in radiographic joint damage over the study period. Scores on musculoskeletal US synovial hypertrophy, power Doppler (PD), and MRI synovitis assessments in individual joints at baseline were significantly associated with progressive radiographic damage (P ‫؍‬ 0.032, P < 0.001, and P ‫؍‬ 0.002, respectively). Furthermore, there was a significant association between the musculoskeletal US PD score at baseline and structural progression over 12 months in totally asymptomatic metacarpophalangeal joints (P ‫؍‬ 0.004) and 12 times higher odds of deterioration in joints with increased PD signal (odds ratio 12.21, P < 0.001).Conclusion. Subclinical joint inflammation detected by imaging techniques explains the structural deterioration in RA patients in clinical remission who are receiving conventional therapy. Our findings reinforce the utility of imaging for the accurate evaluation of disease status and the prediction of structural outcome.

Objective. More timely and effective therapy for rheumatoid arthritis (RA) has contributed to increasing rates of clinical remission. However, progression of structural damage may still occur in patients who have satisfied remission criteria, which suggests that there is ongoing disease activity. This questions the validity of current methods of assessing remission in RA. The purpose of this study was to test the hypothesis that modern joint imaging improves the accuracy of remission measurement in RA.Methods. We studied 107 RA patients receiving disease-modifying antirheumatic drug therapy who were judged by their consultant rheumatologist to be in remission and 17 normal control subjects. Patients underwent clinical, laboratory, functional, and quality of life assessments. The Disease Activity Score 28-joint assessment and the American College of Rheumatology remission criteria, together with strict clinical definitions of remission, were applied. Imaging of the hands and wrists using standardized acquisition and scoring techniques with conventional 1.5T magnetic resonance imaging (MRI) and ultrasonography (US) were performed.Results. Irrespective of which clinical criteria were applied to determine remission, the majority of patients continued to have evidence of active inflammation, as shown by findings on the imaging assessments. Even in asymptomatic patients with clinically normal joints, MRI showed that 96% had synovitis and 46% had bone marrow edema, and US showed that 73% had gray-scale synovial hypertrophy and 43% had increased power Doppler signal. Only mild synovial thickening was seen in 3 of the control subjects (18%), but no bone marrow edema.

Treatment of tenosynovial giant-cell tumors with PLX3397 resulted in a prolonged regression in tumor volume in most patients. (Funded by Plexxikon; ClinicalTrials.gov number, NCT01004861.).