Quantitative MRI as marker of the effectiveness of steroid treatment in patients with Duchenne muscular dystrophy

Due to development of new methods for the treatment of Duchenne muscular dystrophy (DMD), aimed at suppressing inflammatory activity in skeletal muscles, there is a necessity for objective instrumental methods for assessing the effectiveness of the therapy. This method could be selective excitation of the water T2 signal. Aim of the study: to determine the possibility of applying the method of selective excitation of water T2 signal as a quantitative biomarker of the effectiveness of steroid treatment in patients with DMD at different stages of the disease. The study involved 34 DMD boys, who were divided into three groups: ambulant patients taking steroid treatment (n = 14), steroid-naive ambulant patients (n = 10), steroid-naive non-ambulant patients (n = 10) and a control group (n = 10). MRI of the pelvic girdle, thighs and lower legs with multi-slice-multi-echo (MSME) sequences has been done for all subjects. Calculation of the water T2 values has been done by the three-exponential method. Results: There was a significant difference (p < 0.01) between the three study groups, the highest inflammatory activity was determined in the steroid-naive patients and signal intensity was 39.4 ± 1.0 ms for the pelvic girdle muscles, 37.3 ± 1.1 ms for the thighs muscles and 38.1 ± 1.8 ms for the legs muscles. Thus, using of the technique of selectively determination of the signal from water on T2 weighted images can be quantitative biomarker of inflammatory activity and the effectiveness of steroid treatment in patients with Duchenne muscular dystrophy in different stages