PT  - JOURNAL ARTICLE
AU  - Stephanie Finzel
AU  - Sarah L. Manske
AU  - Cheryl C.M. Barnabe
AU  - Andrew J. Burghardt
AU  - Hubert Marotte
AU  - Andrea Scharmga
AU  - Ellen-Margrethe Hauge
AU  - Roland Chapurlat
AU  - Klaus Engelke
AU  - Xiaojuan Li
AU  - Bente C.J. van Teeffelen
AU  - Philip G. Conaghan
AU  - Kathryn S. Stok
TI  - Reliability and Change in Erosion Measurements by High-resolution Peripheral Quantitative Computed Tomography in a Longitudinal Dataset of Rheumatoid Arthritis Patients
AID  - 10.3899/jrheum.191391
DP  - 2021 Mar 01
TA  - The Journal of Rheumatology
PG  - 348--351
VI  - 48
IP  - 3
4099  - http://www.jrheum.org/content/48/3/348.short
4100  - http://www.jrheum.org/content/48/3/348.full
SO  - J Rheumatol2021 Mar 01; 48
AB  - Objective. The aim of this multireader exercise was to assess the reliability and change over time of erosion measurements in patients with rheumatoid arthritis (RA) using high-resolution peripheral quantitative computed tomography (HR-pQCT).Methods. HR-pQCT scans of 23 patients with RA were assessed at baseline and 12 months. Four experienced readers examined the dorsal, palmar, radial, and ulnar surfaces of the metacarpal head (MH) and phalangeal base (PB) of the second and third digits, blinded to time order. In total, 368 surfaces (23 patients´ 16 surfaces) were evaluated per timepoint to characterize cortical breaks as pathological (erosion) or physiological, and to quantify erosion width and depth. Reliability was evaluated by intraclass correlation coefficients (ICC), percentage agreement, and Light k; change over time was defined by means ± SD of erosion numbers and dimensions.Results. ICC for the mean measurements of width and depth of the pathological breaks ranged between 0.819–0.883, and 0.771–0.907, respectively. Most physiological cortical breaks were found at the palmar PB, whereas most pathological cortical breaks were located at the radial MH. There was a significant increase in both the numbers and the dimensions of erosions between baseline and follow-up (P = 0.0001 for erosion numbers, width, and depth in axial plane; P = 0.001 for depth in perpendicular plane).Conclusion. This exercise confirmed good reliability of HR-pQCT erosion measurements and their ability to detect change over time.