usingmagneticresonanceimaging.PDF

Li et al. Arthritis Research Therapy 2010, 12:R173 /content/12/5/R173 RESEARCH ARTICLE Open Access Fully automated system for the quantification of human osteoarthritic knee joint effusion volume using magnetic resonance imaging 1 1 2 2 3 4 Wei Li , François Abram , Jean-Pierre Pelletier , Jean-Pierre Raynauld , Marc Dorais , Marc-André d’Anjou , Johanne Martel-Pelletier2* Abstract Introduction: Joint effusion is frequently associated with osteoarthritis (OA) flare-up and is an important marker of therapeutic response. This study aimed at developing and validating a fully automated system based on magnetic resonance imaging (MRI) for the quantification of joint effusion volume in knee OA patients. Methods: MRI examinations consisted of two axial sequences: a T2-weighted true fast imaging with steady-state precession and a T1-weighted gradient echo. An automated joint effusion volume quantification system using MRI was developed and validated (a) with calibrated phantoms (cylinder and sphere) and effusion from knee OA patients; (b) with assessment by manual quantification; and (c) by direct aspiration. Twenty-five knee OA patients with joint effusion were included in the study. Results: The automated joint effusion volume quantification was developed as a four stage sequencing process: bone segmentation, filtering of unrelated structures, segmentation of joint effusion, and subvoxel volume calculation. Validation experiments revealed excellent coefficients of variation with the calibrated cylinder (1.4%) and sphere (0.8%) phantoms. Comparison of the OA knee joint effusion volume assessed by the developed automated system and by manual quantification was also excellent (r = 0.98; P 0.0001), as w