组织学证据表明,帕金森病(PD)的病理超越了黑质纹状体变性,也影响大脑皮层。定量MRI(qMRI)技术允许评估脑组织组成的变化。然而,与疾病相关的皮质改变的发展和模式尚未在PD中通过qMRI方法得到证实.这项研究的目的是通过定量T1弛豫法研究PD的纵向皮质微结构变化。
13名轻度至中度PD患者和20名匹配的健康受试者在两个时间点进行了高分辨率T1标测,间隔为6.4年(健康受试者:6.5年)。由于MRI伪影,必须排除两名健康受试者的数据。使用FreeSurfer工具箱对皮质T1值进行基于表面的分析。
在PD患者中,在随访期间检测到皮质T1的广泛下降,影响了大部分的颞顶骨和枕骨皮质以及额叶区域。相比之下,健康对照组中与年龄相关的T1降低不那么明显,仅见于额叶外侧,顶叶和颞区。基线时各组间的平均皮质T1值没有差异(p=0.17),但患者在随访时减少(p=0.0004)。患者的皮质T1的年化相对变化较高。健康受试者(患者:-0.72±0.64%/年;健康受试者:-0.17±0.41%/年,p=0.007)。
在PD患者中,观察到皮质微观结构广泛变化的发展,反映在皮质T1的减少。PD患者的T1下降模式超过了生理衰老中发现的正常T1下降模式,并且与先前PD研究中显示的皮质变薄模式有相当大的重叠。因此,皮质T1可能是未来纵向PD研究的一个有希望的额外成像标记.皮质T1减少的生物学机制仍有待进一步阐明。
Histological evidence suggests that pathology in Parkinson\'s disease (PD) goes beyond nigrostriatal degeneration and also affects the cerebral cortex. Quantitative MRI (qMRI) techniques allow the assessment of changes in brain tissue composition. However, the development and pattern of disease-related cortical changes have not yet been demonstrated in PD with qMRI methods. The aim of this study was to investigate longitudinal cortical microstructural changes in PD with quantitative T1 relaxometry.
13 patients with mild to moderate PD and 20 matched healthy subjects underwent high resolution T1 mapping at two time points with an interval of 6.4 years (healthy subjects: 6.5 years). Data from two healthy subjects had to be excluded due to MRI artifacts. Surface-based analysis of cortical T1 values was performed with the FreeSurfer toolbox.
In PD patients, a widespread decrease of cortical T1 was detected during follow-up which affected large parts of the temporo-parietal and occipital cortices and also frontal areas. In contrast, age-related T1 decrease in the healthy control group was much less pronounced and only found in lateral frontal, parietal and temporal areas. Average cortical T1 values did not differ between the groups at baseline (p = 0.17), but were reduced in patients at follow-up (p = 0.0004). Annualized relative changes of cortical T1 were higher in patients vs. healthy subjects (patients: - 0.72 ± 0.64%/year; healthy subjects: - 0.17 ± 0.41%/year, p = 0.007).
In patients with PD, the development of widespread changes in cortical microstructure was observed as reflected by a reduction of cortical T1. The pattern of T1 decrease in PD patients exceeded the normal T1 decrease as found in physiological aging and showed considerable overlap with the pattern of cortical thinning demonstrated in previous PD studies. Therefore, cortical T1 might be a promising additional imaging marker for future longitudinal PD studies. The biological mechanisms underlying cortical T1 reductions remain to be further elucidated.