title: Performance of computer-based analysis using temporal subtraction to assess joint space narrowing progression in rheumatoid patients.
abstract: Our computer-based method can detect the chronological change in joint space width between baseline and follow-up images as the joint space difference index (JSDI). The aim of this study was to verify the sensitivity and specificity of our computer-based method in assessment of joint space narrowing progression in rheumatoid patients. Twenty-seven patients (24 women and 3 men) with rheumatoid arthritis underwent radiography of the bilateral hand at baseline and at 1 year. The joint space narrowing (JSN) of a total of 252 metacarpophalangeal (MCP) joints and 229 carpal joints was assessed by our computer-based method, setting the Sharp/van der Heijde method as the gold standard. We constructed a receiver operating characteristic curve by using the Sharp/van der Heijde method as the gold standard and set the optimal cutoff on JSDI for MCP, carpal, and MCP/carpal joints. We then calculated the sensitivity and specificity for each cutoff in assessment of JSN progression. At the most discriminant cutoff, the sensitivity and specificity of the computer-based method for MCP joints was 78.6 versus 85.3 %, respectively (AUC = 0.837; P < 0.001). Carpal joints revealed a lower sensitivity and specificity with 64.7 and 86.8 % (AUC = 0.775; P < 0.001). Furthermore, the sensitivity and specificity for MCP/carpal joints was 71.0 versus 83.6 %, respectively (AUC = 0.778; P < 0.001). The computer-based method presented a reliable assessment of JSN progression with high sensitivity and specificity and may be useful in follow-up assessment of the joint damage in rheumatoid patients.
authors: Graduate School of Health Sciences, Hokkaido University, North 12 West 5, Kita-ku, Sapporo, 060-0812, Japan. shota-ichikawa@eis.hokudai.ac.jp.
authors: Shota
authors: S
authors: Ichikawa
authors: Faculty of Health Sciences, Hokkaido University, North 12 West 5, Kita-ku, Sapporo, 060-0812, Japan. ktamotamo2@yahoo.co.jp.
authors: Tamotsu
authors: T
authors: Kamishima
authors: Graduate School of Medicine, Hokkaido University, North 15, West 7, Kita-ku, Sapporo, 060-8638, Japan. kensuth@med.hokudai.ac.jp.
authors: Kenneth
authors: K
authors: Sutherland
authors: Katayama Orthopedic Rheumatology Clinic, Toyooka13-4-5-17, Asahikawa, 078-8243, Japan. o-tysss-743211@kzf.biglobe.ne.jp.
authors: Takanobu
authors: T
authors: Okubo
authors: Katayama Orthopedic Rheumatology Clinic, Toyooka13-4-5-17, Asahikawa, 078-8243, Japan. kou@kata-rheum.or.jp.
authors: Kou
authors: K
authors: Katayama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging* / Q000188:drug therapy; D018450:Disease Progression; D005260:Female; D050823:Hand Joints / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012984:Software
chemical_list: D018501:Antirheumatic Agents
keywords: Computer-based joint space analysis; Joint space narrowing; Rheumatoid arthritis; Temporal subtraction