脑动脉粥样硬化斑块中不同类型钙化集合体的矿物学特征及分布规律

钙化是脑动脉粥样硬化的重要指示,并与粥样硬化的发展密切相关。脑动脉粥样硬化斑块钙化灶中存在球状与块状两类不同形貌的矿物集合体,但是关于两类钙化矿物学特征的区别以及其在病灶中空间分布规律的研究仍不充分。选取具有不同程度钙化的脑动脉粥样硬化样品,利用扫描电子显微镜(SEM)及其附带的能谱仪(EDS)、透射电子显微镜(TEM)及其附带的选区电子衍射(SAED)以及拉曼光谱(Raman),对钙化物的形貌、构造以及基于空间分布的物相组成及化学成分的变化进行了研究。研究表明,钙化灶中心由块状钙化构成,周围分布着球状钙化。块状钙化中物相分布不均匀,其中心由碳羟磷灰石(CHA)构成,边缘除CHA外还含有部分无定型磷酸钙(ACP)。球状钙化由白磷钙石(WH)与CHA构成。

Mineralogical characteristics and distribution patterns of different types of calcification in a cerebrovascular atherosclerotic lesion

Cerebral artery calcification is an important indication of atherosclerotic plaques and closely related to the atherosclerotic process. In the cerebral artery, calcification mostly appears as spherical or massive mineral aggregates, but the difference between these two types and their spatial distribution patterns in an atherosclerotic lesion are still not clear. Therefore, we collected and analyzed samples with different stages of calcification by environmental scanning electron microscope (SEM) with energy disperse spectroscopy (EDS), transmission electron microscope (TEM) with selected area electron diffraction (SAED) and Raman spectroscopy (Raman). We studied the morphology, structure and spatial distribution of phase and chemical composition of calcification in the atherosclerotic plaque. The results showed that the center of the calcified area develops massive calcification and its surrounding develops spherical calcification. The center of massive calcification is composed of carbonate hydroxyapatite (CHA) while the edge also contains small fraction of amorphous calcium phosphate (ACP). Spherical calcification is composed of whitlockite (WH) and CHA.