Maschke Matthias, Weber Johannes, Dimitrova Albena, Bonnet Udo, Bohrenkämper Julia, Sturm Sonja, Kindsvater Kerstin, Müller Bernhard W, Gastpar Markus, Diener Hans-Christoph, Forsting Michael, Timmann Dagmar
Department of Neurology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany.
J Neurol. 2004 Jun;251(6):740-6. doi: 10.1007/s00415-004-0420-5.
The aim of the present study was to investigate age-related changes in iron-deposition in dentate nuclei using iron-induced susceptibility effects in magnetic resonance imaging. MR images from 74 healthy subjects (age range 20-68 years) were obtained using a three-dimensional (3D) T1-weighted fast low angle shot (FLASH) echo sequence. Signal intensities of the dentate nuclei and cerebellar white matter were bilaterally measured independently by three blinded investigators. The signal intensities of dentate nuclei were intraindividually normalised to the corresponding signal intensities of the cerebellar white matter of corresponding slices. Mean normalised signal intensities were correlated with age and compared between different age decades and gender. Intraclass correlation coefficients were high (dentate nuclei: 0.98, cerebellar white matter: 0.75) indicating sufficient interrater reliabilities for the determination of signal intensities. Bland-Altman analysis confirmed this finding. The normalised mean signal intensity of the dentate nuclei correlated inversely with age (r = -0.462, p < 0.0001). Comparison of age decades revealed that significant decreases took place between the third and fourth decade and to a lesser degree between the fourth and fifth decade. Moreover, variability of normalised mean signal intensities of the dentate nuclei increased significantly with age (r = 0.964, p = 0.008). There were no differences of the normalised mean signal intensities between genders. The present study revealed an age-dependent decrease of signal intensities in dentate nuclei most likely reflecting an age-dependent increase in dentate iron concentration. These age-dependent changes have to be taken into account in interpretation of disease related MR changes of cerebellar nuclei in patients with degenerative or acquired cerebellar ataxia.
本研究的目的是利用磁共振成像中铁诱导的磁化率效应，调查齿状核中铁沉积的年龄相关变化。使用三维（3D）T1加权快速低角度激发（FLASH）回波序列，获取了74名健康受试者（年龄范围20 - 68岁）的磁共振图像。由三名不知情的研究人员独立双侧测量齿状核和小脑白质的信号强度。齿状核的信号强度在个体内被标准化为相应切片中小脑白质的相应信号强度。将平均标准化信号强度与年龄进行相关性分析，并在不同年龄十年组和性别之间进行比较。组内相关系数较高（齿状核：0.98，小脑白质：0.75），表明信号强度测定具有足够的评分者间可靠性。Bland - Altman分析证实了这一发现。齿状核的标准化平均信号强度与年龄呈负相关（r = -0.462，p < 0.0001）。年龄十年组比较显示，在第三个和第四个十年之间有显著下降，在第四个和第五个十年之间下降程度较小。此外，齿状核标准化平均信号强度的变异性随年龄显著增加（r = 0.964，p = 0.008）。性别之间的标准化平均信号强度没有差异。本研究揭示了齿状核信号强度随年龄下降，最有可能反映齿状核铁浓度随年龄增加。在解释患有退行性或获得性小脑共济失调患者小脑核的疾病相关磁共振变化时，必须考虑这些年龄依赖性变化。
