X-ray microanalysis of mineralized deposits in a variety of pathological conditions in the brain

Although a small degree of mineralization can be a common occurrence without associated pathological symptoms, certain diseases of the brain do however exhibit distinct increases in mineralization with characteristic distributions l>2. In this study, tissues from a number of these disorders were prepared for x-ray microanalysis in several ways. Where possible, material was slam frozen on a liquid nitrogen cooled polished copper block, cryosections prepared and freeze dried in the scanning transmission electron microscope (STEM) using a cold stage prior to analysis by energy dispersive x-ray spectrometry (EDS). In addition, samples were freeze substituted for several days, embedded in LR white and cut on dry knives before analysis. Where only formalin fixed paraffin embedded materials were available, .5μ.m sections were cut and mounted on carbon planchets. The specimens were then deparaffinized with xylene and viewed with the backscatter electron detector (BEI) in the scanning electron microscope (SEM) and analyzed by EDS.