Gorell J M, Ordidge R J, Brown G G, Deniau J C, Buderer N M, Helpern J A
Department of Neurology, Henry Ford Hospital and Health Sciences Center, Detroit, MI 48202, USA.
Neurology. 1995 Jun;45(6):1138-43. doi: 10.1212/wnl.45.6.1138.
Elevated iron levels in the substantia nigra (SN) of the brain in Parkinson's disease (PD) may mediate lipid peroxidative reactions, promoting SN neuronal death. To assess SN iron accumulation in living PD patients and its relation to motor performance, we measured, in 13 nondemented PD patients and 10 normal control subjects, simple reaction time (SRT) and simple movement time (SMT), followed by head MRI in a 3-tesla system. We measured T2 and T2* in the right and left SN of all subjects and calculated R2', the relaxation rate due to local magnetic field in-homogeneities, from these values. Asymmetries of 1/T2 (R2), 1/T2* (R2*), or R2' versus asymmetries of SRT and SMT were assessed in eight PD subjects who had not taken anti-PD medication(s) for 12 hours. The average of right and left SN values for R2 was lower, and R2* and R2' were higher, in PD patients than in controls (R2, p = 0.046; R2*, p = 0.001; R2', p < 0.001). R2' best predicted group differences. The asymmetry of SRT performance was highly correlated with asymmetries of SN R2* (0.91; p = 0.001) and R2' (0.72; p = 0.03). These results strongly suggest that the increases in iron levels seen postmortem in the SN in PD are reflected in increased iron-related MRI contrast at 3 tesla in living PD patients. Correlations with motor performance in PD suggest that the clinical severity of PD may be related to SN iron accumulation.
帕金森病（PD）患者大脑黑质（SN）中铁水平升高可能介导脂质过氧化反应，促使SN神经元死亡。为评估活体PD患者SN中铁的蓄积情况及其与运动表现的关系，我们对13例无痴呆的PD患者和10名正常对照者测量了简单反应时间（SRT）和简单运动时间（SMT），随后在3特斯拉系统中进行头部MRI检查。我们测量了所有受试者左右SN的T2和T2*，并根据这些值计算了由于局部磁场不均匀性导致的弛豫率R2'。在8例未服用抗PD药物达12小时的PD受试者中，评估了1/T2（R2）、1/T2*（R2*）或R2'的不对称性与SRT和SMT不对称性的关系。PD患者SN左右值的R2平均值较低，而R2和R2'较高，与对照组相比有差异（R2，p = 0.046；R2，p = 0.001；R2'，p < 0.001）。R2'最能预测组间差异。SRT表现的不对称性与SN的R2*（0.91；p = 0.001）和R2'（0.72；p = 0.03）的不对称性高度相关。这些结果有力地表明，PD患者死后SN中铁水平的升高在活体PD患者3特斯拉的MRI检查中表现为铁相关对比度增加。与PD运动表现的相关性表明，PD的临床严重程度可能与SN中铁的蓄积有关。
