Quantifying bone marrow inflammatory edema in the spine and sacroiliac joints with thresholding

BMC Musculoskeletal Disorders

Susanne J. Pedersen¹  Leslie R. Euceda²  Ioanna Chronaiou²  Beathe Sitter²  Ruth S. Thomsen³  Mari Hoff³  Else M. Huuse⁴ 

[1] Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet - Glostrup;Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, NTNU – Norwegian University of Science and Technology;Department of Public Health and Nursing, Faculty of Medicine and Health Sciences, NTNU – Norwegian University of Science and Technology;Department of Radiology and Nuclear Medicine, St Olav’s Hospital, University Hospital in Trondheim;

关键词: Psoriatic arthritis;    MRI;    Image processing;    SPARCC;    Bone marrow inflammatory edema;   

DOI  :  10.1186/s12891-017-1861-1

来源: DOAJ

【 摘 要 】

Abstract Background Psoriatic Arthritis (PsA) is a chronic inflammatory arthritis that develops in patients with psoriasis. Inflammatory edema in the spine may reflect subclinical disease activity and be a predictor of radiographic progression. A semi-quantitative method established by the spondyloarthritis research consortium of Canada (SPARCC) is commonly used to assess the disease activity in MR images of the spine. This study aims to evaluate thresholding for quantification of subtle bone marrow inflammation in the spine and the sacroiliac (SI) joints of patients with PsA and compare it with the SPARCC scoring system. Methods Short tau inversion recovery (STIR) MR images of the spine (N = 85) and the SI joints (N = 95) of patients with PsA (N = 41) were analyzed. A threshold was applied to visible bone marrow in order to mask areas with higher signal intensity, which are consistent with inflammation. These areas were considered as inflammatory lesions. The volume and relative signal intensity of the lesions were calculated. Results from thresholding were compared to SPARCC scores using linear mixed-effects models. The specificity and sensitivity of thresholding were also calculated. Results A significant positive correlation between the volumes and mean relative signal intensities, which were calculated by thresholding analysis, and the SPARCC scores was detected for both spine (p < 0.001) and SI joints (p < 0.001). For the spine, thresholding had sensitivity and specificity of 83% and 76% respectively, while for the SI joints the values were 51% and 88% respectively. Conclusions Thresholding allows quantification of subtle bone marrow inflammatory edema in patients with psoriatic arthritis, and could support SPARCC scoring of the spine. Improved image processing and inclusion of automatic segmentation are required for thresholding of STIR images to become a rapid and reliable method for quantitative measures of inflammation. Trial registration NCT02995460 (December 14, 2016) – Retrospectively registered.

【 授权许可】

Unknown