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

Because of the necessity of objective instrumental methods for assessing the state of skeletal musculature in patients with Duchenne muscular dystrophy, the aim of our work was to evaluate the correlation between manual methods of assessment of the muscle strength and the results of magnetic resonance imaging (MRI) of the skeletal muscles of lower limbs. We have examined 15 corticosteroid-naive patients with Duchenne muscular dystrophy. Patients were divided into 2 groups: ambulant patients (average age 8.1 years) and non-ambulant patients (mean age 12.7 years). Muscle strength of lower extremities of all patients has been evaluated by Medical Research Council scale and MRI of skeletal muscles of the pelvic girdle, thighs and lower legs has been performed. The following results have been obtained: ambulant patients have been characterized by a high correlation of MRC scale and MRI of the lower extremities in the evaluation of the pelvic girdle and thighs muscles and the total score (pelvic girdle, thighs and lower legs) and salient correlation in the evaluation of the lower legs muscles. Non-ambulant patients have been characterized by moderate correlation in the evaluation of pelvic girdle and thighs muscles, as well as the total score of lower limbs. There was no correlation between MRC and MRI results in the muscles of the lower legs. Magnetic resonance tomography is able to reliably estimate the degree of fatty infiltration in Duchenne muscular dystrophy and is the method of choice in the diagnosis and evaluation of the severity of this disease.