title: Brief Report: Development and Validation of a Semiautomated Method to Measure Erosion Volume in Inflammatory Arthritis by Computed Tomography Scanning.
abstract: OBJECTIVE
  Valid measurement of erosion volume in rheumatoid arthritis (RA) will facilitate the testing of treatments that may help to heal erosion. This study was undertaken to develop and validate a software method to measure erosion volume on computed tomography (CT) scans of the hand and wrist.
  
  
  METHODS
  Duplicate CT acquisitions of both hands of 5 patients with RA were evaluated using a semiautomated software tool to measure erosion volume in the entire hand and wrist and in each of 6 subregions. Reproducibility was quantified using the intraclass correlation coefficient (ICC), root mean square standard deviation (RMSSD), and coefficient of variation (CV), and the analysis was performed at the level of the hand (n = 10) and the subject (n = 5).
  
  
  RESULTS
  The ICCs between 2 repositioned acquisitions were excellent, ranging from 0.97 to 1.00. At the hand level, the RMSSD was 15.6 mm(3) with a CV of 7.3%, and the CVs at the 6 regions ranged from 7.6% to 21.0%. At the subject level, the RMSSD was 31.2 mm(3) with a CV of 3.7%, and the CVs at the 6 regions ranged from 0.5% to 15.8%.
  
  
  CONCLUSIONS
  We have developed a novel semiautomated software method to measure erosion volume on hand and wrist CT scans. The method is reproducible and can be used to detect changes in erosion volume. This will facilitate the testing of treatments intended to reduce erosion volume.
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Duryea
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Ruby
authors.initials: R
authors.lastname: Russell
authors.affiliation: University of Massachusetts Medical School, Worcester.
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Gravallese
authors.affiliation: University of Massachusetts Medical School, Worcester.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Kay
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Roger
authors.initials: R
authors.lastname: Han
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Bing
authors.initials: B
authors.lastname: Lu
authors.affiliation: Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Solomon
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging*; D005260:Female; D050276:Hand Bones / Q000000981:diagnostic imaging*; D050823:Hand Joints / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed