Page 89 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints
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 AUSCAN physical, mean (SD) [0-900]
High-resolution MRI of cartilage in finger joints
We acquired 19 MRI image sets of the dominant hand of healthy controls and 48 MRI Image sets of patients diagnosed with hand OA. The images of 5 hand OA patients and 1 healthy control were used for training and calibration. Two image sets of hand OA patients were excluded because of poor image quality. In the remaining image sets of 18 healthy controls and 41 patients, 3 joints could not be rated on the PD images and 1 joint on the SPGR images because of artefacts. Details of patient characteristics can be found in Table 1.
Table 1. Characteristics of participants in final reading Female, n (%)
Age, mean (range) yrs
Right hand scanned, n (%)
ACR criteria hand OA, n (%)
AUSCAN pain, mean (SD) [0-500] 201(114) . 5
Hand grip strength of scanned hand, mean (SD) kg
ACR, American College of Rheumatology; AUSCAN, Australian/Canadian Hand Index
The inter-reader and intra-reader PEA and PCA values of both scores were comparable (Table 2). The inter-reader reliability kappa score of the hrMRI cartilage score was significantly higher than for inter-bone distance. The intra- reader reliability was similar for both features. Readers agreed in 170/233 joints on the inter bone distance scale. They agreed on normal inter-bone distance in 142 joints, reduced inter-bone distance grade 1 in 25 joints and grade 2 in 3 joints. Most discrepancies in the inter-bone distance score were between grade 0 (normal) and grade 1 (narrowing without bone-bone contact) (50 out of the 63 discrepant joints). In these instances reader 2 scored higher in 38/50 discrepant joints. 24 of these discrepancies were in healthy controls. Readers agreed in 176/234 joints on the hrMRI cartilage score. They agreed on normal cartilage in 137 joints, cartilage damage grade 1 in 21 joints, grade 2 in 16 joint and grade 3 in 2 joints. The observers disagreed the most on grade 0 (normal) versus grade 1 (thinning of cartilage >10% of surface) and grade 1 versus grade 2 (thinning with complete cartilage loss without bone-bone contact) in 23 joint and 22 joints, respectively. Reader 1 scored higher in 42/45 discrepancies.
Hand OA patients (n=41)
Healthy controls (n=18)
36 (85)
59 (40-80) 32 (78)
31 (76)
18 (100) 25 (18-31) 12 (67)
0 (0)

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