Strain sonoelastography of inflammatory myopathies: comparison with clinical examination, magnetic resonance imaging and pathologic findings

To evaluate strain sonoelastography (SSE) in patients with inflammatory myopathies (IM) compared with clinical examination, MRI and pathologic findings. 18 lesions from 17 consecutive patients with IM (5 males and 12 females; mean age, 41.2 years; range, 11-67 years) were assessed with SSE after MRI. The ratio of strain in the target muscle (A) and a nearby normal muscle (B), defined as the strain index value (SR) (B/A), was calculated automatically. Elastograms were assigned an elasticity score according to the degree and distribution of strain induced by manual compression. Ultrasonography and MRI were analyzed in conjunction with clinical information, biochemical data, final clinical diagnosis and grading of pathology. Correlations between SR and qualitative analyses of MRI and ultrasonography, elasticity score, biochemical data and final clinical diagnosis were analyzed using Pearson's correlation coefficient. The SR of the target muscles was high in patients with IM (mean 3.14; range, 0.95-5.93 ± 1.42). The correlations between SR and pathologic grading and elasticity score were statistically significant (p