University of Basel Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostic and Interventional Neuroradiology, Petersgraben 4, CH-4031 Basel, Switzerland.
Neuromuscul Disord. 2012 Oct 1;22 Suppl 2:S107-10. doi: 10.1016/j.nmd.2012.05.014.
We examined the influence of a single exercise session on quantitative muscle fat fraction MRI measurements. Ten healthy volunteers were scanned on a 3T body scanner before and after a session of bilateral squats until muscular fatigue. Axial in- and opposed phase images were acquired at a fixed distance from the knee joint and fat fractions were calculated using a 2-point Dixon technique as well as muscle cross sectional area at the same position. After the squat session, calculated fat fraction in the quadriceps bilaterally appeared to be significantly decreased, while all but one non-exercised muscles showed no change. In conclusion exercise might modify the measured apparent fat fraction. Trials using quantitative MRI should consider the timing of scanning sessions and physical examinations to avoid bias caused by the influence of exercise on measurements.
我们研究了单次运动对定量肌肉脂肪分数 MRI 测量的影响。10 名健康志愿者在 3T 体部扫描仪上进行双侧深蹲运动直至肌肉疲劳，在运动前后分别进行扫描。在膝关节固定距离处采集轴位同相位和反相位图像，并使用 2 点 Dixon 技术计算脂肪分数以及同一位置的肌肉横截面积。深蹲运动后，双侧股四头肌的计算脂肪分数明显降低，而除了一块非运动肌肉外，其他肌肉均无变化。总之，运动可能会改变测量的表观脂肪分数。使用定量 MRI 的试验应考虑扫描时间和体格检查的时间，以避免运动对测量结果的影响造成的偏差。
