Lyu Xiaohong, Gao Yue, Liu Qiang, Zhao Heng, Zhou Huadong, Pan Shinong
Department of Radiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110004, China.
Department of Radiology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, 121000, China.
BMC Musculoskelet Disord. 2021 Mar 2;22(1):239. doi: 10.1186/s12891-021-04085-z.
To explore the value of magnetic resonance quantitative analysis using diffusion tensor imaging, T2 mapping, and intravoxel incoherent motion in the evaluation of eccentric exercise-induced muscle damage and to compare the effects of various eccentric exercise modes at different time points in rats.
A total of 174 Sprague-Dawley male rats were randomly divided into five groups: control, once-only exercise, continuous exercise, intermittent exercise, and once-fatigue exercise groups. Each experimental group was divided into seven time-subgroups: 0.5 h, 24 h, 48 h, 72 h, 96 h, 120 h and 168 h after exercise. The quadriceps femoris muscles were then scanned using magnetic resonance imaging. The apparent diffusion coefficient and fractional anisotropy values of diffusion tensor imaging, T2 values of T2 mapping, D and D* values of intravoxel incoherent motion and optical density values of desmin were measured. Associations among different eccentric exercise programmes, magnetic resonance imaging findings, and histopathological results were evaluated. Dunnett's test, two-way repeated measures analysis of variance, and Pearson correlation analysis were used for statistical analysis.
Diffusion tensor imaging showed that the number of muscle fibre bundles decreased to varying degrees with different time points and eccentric exercises. Apparent diffusion coefficient values of the exercise groups showed a trend that first increased and then decreased, the opposite of fractional anisotropy. The specimens in all eccentric exercise programmes showed high signal T2 values after exercise, the highest among which was in the once-fatigue exercise group. D and D* in the experimental groups were significantly higher than those in the control group at 0.5-48 h after exercise. The apparent diffusion coefficient, fractional anisotropy, T2, D and D* values correlated with the optical density values of desmin.
Diffusion tensor imaging, T2 mapping, and intravoxel incoherent motion technology accurately reflect the degree of skeletal muscle damage and recovery associated with eccentric exercise. The degree of muscle damage was the lowest in the continuous exercise group and the highest in the once-fatigue exercise group, which may provide more information and guidance for the formulation of physical and athletic training programmes.
探讨使用扩散张量成像、T2 映射和体素内不相干运动进行磁共振定量分析在评估离心运动诱导的肌肉损伤中的价值，并比较不同离心运动模式在大鼠不同时间点的影响。
将 174 只雄性 Sprague-Dawley 大鼠随机分为五组：对照组、单次运动组、连续运动组、间歇运动组和单次疲劳运动组。每个实验组再分为七个时间亚组：运动后 0.5 小时、24 小时、48 小时、72 小时、96 小时、120 小时和 168 小时。然后使用磁共振成像对股四头肌进行扫描。测量扩散张量成像的表观扩散系数和分数各向异性值、T2 映射的 T2 值、体素内不相干运动的 D 和 D*值以及结蛋白的光密度值。评估不同离心运动方案、磁共振成像结果和组织病理学结果之间的关联。采用 Dunnett 检验、双向重复测量方差分析和 Pearson 相关分析进行统计分析。
扩散张量成像显示，不同时间点和离心运动后肌纤维束数量有不同程度减少。运动组的表观扩散系数值呈先升高后降低趋势，与分数各向异性相反。所有离心运动方案的标本运动后 T2 值均呈高信号，其中单次疲劳运动组最高。实验组运动后 0.5 - 48 小时的 D 和 D值显著高于对照组。表观扩散系数、分数各向异性、T2、D 和 D值与结蛋白的光密度值相关。
扩散张量成像、T2 映射和体素内不相干运动技术准确反映了与离心运动相关的骨骼肌损伤程度和恢复情况。连续运动组的肌肉损伤程度最低，单次疲劳运动组最高，这可能为制定体育和运动训练计划提供更多信息和指导。
