Subtle radiographic progression at 6 months can be detected using automated quantitative software in rheumatoid arthritis while receiving tocilizumab

Abstract

ABSTRACT Objectives We investigated whether our in-house software equipped with partial image phase-only correlation (PIPOC) can detect subtle radiographic joint space narrowing (JSN) progression at 6 months and predict JSN progression in rheumatoid arthritis (RA) patients receiving Tocilizumab. Methods The study included 39 RA patients who were treated with Tocilizumab. Radiological progression of the finger joints was evaluated according to the Genant-modified Sharp score (GSS) at 0, 6, and 12 months. Results The success rate of the software for joint space width (JSW) measurement was 96.8% (449/464). The 0–12-month JSW change by the software was significantly greater in joints with the 0–6-month PIPOC (+) group than the 0–6-month PIPOC (–) group (P < 0.001). The 0–12-month JSW change by the software was 0–12 month GSS (+) than with 0–12 month GSS (–) (P = 0.02). Here, ‘(+)’ indicates the JSN progression during the follow-up period. Linear regression tests showed significant correlations between the 0–6 month and the 0–12 month PIPOC in the left second and third metacarpophalangeal joints (R2 = 0.554 and 0.420, respectively). Conclusions Our in-house software equipped with PIPOC could predict subsequent JSN progression with only short-term observations.