Farkas Eszter, de Vos Rob A I, Donka Gergely, Jansen Steur E N, Mihály András, Luiten Paul G M
Department of Anatomy, School of Medicine, University of Szeged, P.O. Box 427, 6701, Szeged, Hungary.
Acta Neuropathol. 2006 Feb;111(2):150-7. doi: 10.1007/s00401-005-0007-y. Epub 2006 Feb 2.
Clinical studies have identified white matter (WM) lesions as hyperintensive regions in the MRI images of elderly patients. Since a cerebrovascular origin was attributed to such lesions, the present analysis set out to define the microvascular histopathologic changes in the periventricular WM in the aged. Post-mortem samples of the frontal, parietal, and occipital periventricular WM of 40-90-year-old subjects were prepared for quantitative light and electron microscopy. Light microscopic examination revealed microvascular fibrohyalinosis as the most common type of microvascular damage in the elderly. Ultrastructural analysis identified the microvascular thickening as collagen deposits affecting the basement membrane. The vascular density did not correlate with the age. The basement membrane pathology significantly increased, while the number of intact microvessels gradually decreased, with advancing age in the frontal and occipital WM. Finally, peripheral atherosclerosis coincided with massive microvascular fibrosis, particularly in the frontal WM. Our results demonstrate an age-related microvascular degeneration in the periventricular WM, which may contribute to the development of WM lesions by hindering a sufficient supply of nutrients to the affected WM sites. Furthermore, the data accord with previous observations identifying the frontal lobe as the site at which WM vulnerability is most pronounced. Finally, atherosclerosis in large, peripheral vessels is considered to be a predictive marker of microvascular pathology in the WM.
临床研究已将白质（WM）病变确定为老年患者MRI图像中的高强度区域。由于此类病变被认为源于脑血管，因此本分析旨在确定老年人脑室周围白质的微血管组织病理学变化。对40至90岁受试者的额叶、顶叶和枕叶脑室周围白质的尸检样本进行了定量光学和电子显微镜检查。光学显微镜检查显示，微血管纤维玻璃样变性是老年人最常见的微血管损伤类型。超微结构分析确定微血管增厚是影响基底膜的胶原沉积。血管密度与年龄无关。在额叶和枕叶白质中，随着年龄的增长，基底膜病理显著增加，而完整微血管的数量逐渐减少。最后，外周动脉粥样硬化与大量微血管纤维化同时出现，尤其是在额叶白质中。我们的结果表明，脑室周围白质存在与年龄相关的微血管变性，这可能通过阻碍受影响的白质部位获得足够的营养供应而导致白质病变的发展。此外，这些数据与之前将额叶确定为白质易损性最明显部位的观察结果一致。最后，大的外周血管中的动脉粥样硬化被认为是白质中微血管病理的预测标志物。
