应用SWI技术分析帕金森病患者脑铁沉积与运动症状相关性的研究

Analysis of the correlation between brain iron deposition and motor symptoms in patients with Parkinson's disease using susceptibility weighted imaging technique

摘要:

目的： 使用磁敏感加权成像（susceptibility weighted imaging，SWI）检测脑核团铁含量，并评估脑铁沉积与帕金森病（Parkinson's disease，PD）运动症状的相关性。 方法： 纳入35例PD患者和41例年龄和性别匹配的健康受试者在3 T核磁共振完成SWI检查，在相位图中测量各核团的相位值。收集Hoehn-Yahr分级、统一帕金森病评分量表（Unified Parkinson's Disease Rating Scale，UPDRS）第Ⅰ、Ⅱ、Ⅲ部分评分及总分等临床资料。根据Hoehn-Yahr分级将PD组分为早期组（≤2级）及中晚期组（>2级），PD早期组中（Hoehn-Yahr分级≤1.5级）根据其运动症状分为患肢同侧组及对侧组。比较各组间各核团相位值差异，并分析相位值与铁含量、UPDRS评分等的相关性。 结果： 对照组各核团相位值与正常人脑铁含量呈负线性相关（r=-0.809，P=0.028）。PD组黑质致密部（substantia nigra pars compactac，SNc）相位值较对照组显著降低（P=0.011），中晚期PD组SNc相位值显著低于对照组（P=0.014），PD早期患肢同侧组及对侧组SNc相位值差异显著（P<0.001），对侧组SNc相位值较对照组明显降低（P=0.032）。PD组SNc相位值与UPDRS-Ⅱ评分负线性相关（r=-0.364，P=0.032）。 结论： 在PD进展过程中SNc铁含量逐渐增加，以中晚期为著。SNc铁沉积在PD早期的不对称性分布与运动症状不对称有关。PD患者SNc铁沉积与运动症状严重程度呈正线性相关，提示其可能作为监测疾病进展的生物标志物。

Abstract:

Objective: To detect iron content in deep grey matter nucleus of brain by susceptibility weighted imaging (SWI) and to assess the correlation between iron deposition and motor symptoms of Parkinson's disease (PD). Methods: This study enrolled 35 PD patients and 41 age-and sex-matched healthy controls who completed SWI examination on 3 T MRI. The phase value of each nucleus was measured in the phase images. The clinical data such as Hoehn-Yahr stage, scores of the Unified Parkinson's Disease Rating Scale (UPDRS) partⅠ, Ⅱ, Ⅲ and total score were collected. According to the Hoehn-Yahr classification, the PD group was divided into the early group (≤2 grade) and the mid-late group (>2 grade), and in the early group (Hoehn-Yahr classification≤1.5 grade) was divided into the ipsilateral and contralateral groups according to the asymmetry of their motor symptoms, and the distribution of iron content. The differences of phase value of each nucleus in each group were compared, and the correlation between phase value and iron content, UPDRS score and so on were analyzed. Results: The phase value of each nucleus in the control group had a negative linear correlation with the iron content of normal human brain reported in the literature (r=-0.809, P=0.028). The phase value of substantia nigra pars compactac (SNc) in the PD group was significantly lower than that of the control group (P=0.011), and the phase value of SNc portion in the mid-late PD group was significantly lower than that of the control group (P=0.014). The SNc phase value of the ipsilateral and contralateral group in the early PD group was significantly different (P<0.001), and the SNc phase value of the contralateral group was significantly lower than that of the control group (P=0.032). The phase value of SNc of PD group showed a negatively linear correlation with UPDRS-Ⅱscore (r=-0.364, P=0.032). Conclusion: The iron content of SNc gradually increase during the progression of PD, mainly in the middle and late stages. The asymmetric distribution of SNc iron deposits in early PD is related to the asymmetry of motor symptoms. Iron deposition in SNc of PD patients is positively linear correlated with motor symptoms, indicating that it may function as a biomarker for monitoring PD progression.