Diffusion tensor imaging in evaluation of thigh muscles in patients with polymyositis and dermatomyositis

OBJECTIVE To explore the diffusion tensor imaging (DTI) characteristics of thigh muscles in patients with polymyositis (PM) and dermatomyositis (DM). METHODS 12 patients with known PM/DM and 10 healthy volunteers were enrolled in this study. Both DTI and conventional MR sequences were performed on both thighs of all subjects. Apparent diffusion coefficient (ADC), fractional anisotropy (FA) and three eigenvalues were compared between the PM/DM group and the healthy group. One-way analysis of variance and Student's t-test were used for statistical analyses with a significance of p 0.05). CONCLUSION DTI can be used to quantitatively evaluate the anisotropic diffusion characteristics of muscles in patients with PM/DM. ADVANCES IN KNOWLEDGE A new application of DTI is proposed for inflammatory myopathies. The results show that ADC and the three eigenvalues were significantly different between diseased and normal muscles, a finding of potential value in both diagnosis and treatment monitoring of myopathies