Study on T2 mapping in thigh muscles of patients with Duchenne muscular dystrophy

Abstract

Objective Use T 2 mapping to evaluate the fatty infiltration of thigh muscles in Duchenne muscular dystrophy (DMD) patients, so as to analyze the value of T 2 mapping and T 2 relaxation time in the diagnosis of DMD. Methods Sixteen DMD patients who were admitted from January 2004 to January 2013 in our hospital and were diagnosed by clinical confirmation and gene detection have participated into this study. These 16 male patients formed the DMD group. Six age- and sex-matched healthy boys were selected as control group. Clinical functional scale, thigh axial T 1 WI-turbo spin echo (TSE), T 2 WI-TSE, spectral attenuated inversion recovery (SPAIR)-T 2 WI and T 2 mapping were performed in both 2 groups. T 1 WI fatty infiltration scale and T 2 relaxation time were assessed in adductor magnus, gracilis, adductor longus, sartorius, rectus femoris, vastus intermedius, vastus medialis, vastus lateralis, biceps femoris, semitendinosus and semimembranosus. Spearman rank correlation was conducted to assess the correlation between T 2 relaxation time and T 1 WI fatty infiltration scale or clinical functional scale. Results Compared with control group, the T 2 relaxation time of 8 muscles (adductor magnus, adductor longus, rectus femoris, vastus intermedius, vastus medialis, vastus lateralis, biceps femoris and semimembranosus) in DMD group were prolonged ( P < 0.05, for all). The longest average T 2 relaxation time was found in adductor magnus. The T 2 relaxation time of adductor magnus, vastus intermedius, vastus lateralis, biceps femoris, rectus femoris, adductor longus and vastus medialis was positively correlated with T 1 WI fatty infiltration scale ( P < 0.05, for all), and the T 2 relaxation time of adductor magnus and semimembranosus was positively correlated with clinical funetional scale ( P < 0.05, for all). A positive correlation was found in adductor magnus between T 2 relaxation time and both T1WI fatty infiltration scale ( r s = 0.867, P = 0.000) and clinical functional scale ( r s = 0.651, P = 0.005). Conclusions T 2 relaxation time could be used in the quantitative and objective analysis of DMD clinical severity, and adductor magnus was considered to be the most valuable muscle to reflect the clinical severity of DMD. DOI: 10.3969/j.issn.1672-6731.2015.06.004