Bryan W W, Reisch J S, McDonald G, Herbelin L L, Barohn R J, Fleckenstein J L
Department of Neurology, The University of Texas Southwestern Medical Center at Dallas, 75235-8897, USA.
Neurology. 1998 Jul;51(1):110-3. doi: 10.1212/wnl.51.1.110.
To characterize leg muscle abnormalities in patients with ALS using MRI, and to correlate MRI with standard neurologic measures of motor neuron dysfunction.
Eleven ALS patients were studied twice (once at baseline and again after 4 months) and compared with eight normal control subjects. MRI data of the lower extremities were compared with tibialis anterior compound muscle action potential amplitude (CMAPa) and foot dorsiflexion maximal voluntary isometric contraction (MVIC).
Muscle MRI was abnormal by visual inspection in six of 11 patients. The mean muscle T1 time and muscle volume were not different in patients compared with normal control subjects (p > 0.1). However, the mean T2 times were increased in the patients compared with normal control subjects (p = 0.009). T1 times did not correlate with CMAPa or MVIC. Muscle volume correlated with MVIC (r = 0.73 to 0.78, p < 0.02) but not with CMAPa (p > 0.05). There was a strong negative correlation (r < -0.8, p < or = 0.01) between muscle T2 time and MVIC and CMAPa. Also, the change in T2 relaxation time correlated with the change in CMAPa as the disease progressed (r = -0.63, p = 0.037).
Of the MRI characteristics studied, T2 relaxation time was the best indicator of motor neuron dysfunction and may have a role in objective evaluation of motor neuron dysfunction.
利用磁共振成像（MRI）对肌萎缩侧索硬化症（ALS）患者的腿部肌肉异常进行特征描述，并将MRI与运动神经元功能障碍的标准神经学测量指标相关联。
对11例ALS患者进行了两次研究（一次在基线时，另一次在4个月后），并与8名正常对照受试者进行比较。将下肢的MRI数据与胫前肌复合肌肉动作电位幅度（CMAPa）和足背屈最大自主等长收缩（MVIC）进行比较。
11例患者中有6例经肉眼观察肌肉MRI异常。与正常对照受试者相比，患者的平均肌肉T1时间和肌肉体积无差异（p>0.1）。然而，与正常对照受试者相比，患者的平均T2时间增加（p = 0.009）。T1时间与CMAPa或MVIC无相关性。肌肉体积与MVIC相关（r = 0.73至0.78，p < 0.02），但与CMAPa无关（p>0.05）。肌肉T2时间与MVIC和CMAPa之间存在强烈的负相关（r < -0.8，p≤0.01）。此外，随着疾病进展，T2弛豫时间的变化与CMAPa的变化相关（r = -0.63，p = 0.037）。
在所研究的MRI特征中，T2弛豫时间是运动神经元功能障碍的最佳指标，可能在运动神经元功能障碍的客观评估中发挥作用。
