T2 mapping and fat quantification of lumbar paraspinal muscle in ankylosing spondylitis: a case control study

Abstract

Abstract Background To compare changes in the composition of paraspinal muscles of patients with ankylosing spondylitis (AS) and matched healthy controls using T2 mapping and T2 IDEAL and correlate the quantitative magnetic resonance imaging (qMRI) results with clinical assessments of AS patients. Method In total, 37 AS patients and 37 healthy controls were enrolled in the case control study. T2 mapping with and without fat saturation and IDEAL imaging were used to assess the multifidus (MF) and erector spinae (ES) at the levels of L3/L4 and L4/L5 for all subjects. Mean T2non-fatsat, T2fat, T2fatsat, cross-sectional area (CSA), and fat fraction (FF) were compared between AS and healthy controls. Correlations of qMRI results with clinical assessments were analyzed in AS. Results Significantly elevated mean T2non-fatsat values and the FF of the MF and ES at both levels were observed in AS and compared to the controls (p 0.05). Conclusions Our findings indicate that using a combination of IDEAL and T2 mapping may provide deeper insights into the pathophysiological degeneration of paraspinal muscles in AS.

Keywords

• Ankylosing spondylitis
• Paraspinal muscle
• Muscle degeneration
• Fat infiltration
• T2 mapping
• T2 IDEAL