. A manual of diseases of the nervous system. xtravasation at the onset. At a laterperiod the yellow or white opaque aspect is changed to a greytranslucent ap>pearance, from the absorption of the fatty products ofdegeneration, and an increase in the connective tissue. If themyelitis is very limited in extent, cavities may be formed within thecord. The microscopical appearances in myelitis vary much according tothe duration and form of the inflammation. In the fresh state themost conspicuous objects are the products of degeneration of thefibres, granules and masses of myelin, and granule cor
. A manual of diseases of the nervous system. xtravasation at the onset. At a laterperiod the yellow or white opaque aspect is changed to a greytranslucent ap>pearance, from the absorption of the fatty products ofdegeneration, and an increase in the connective tissue. If themyelitis is very limited in extent, cavities may be formed within thecord. The microscopical appearances in myelitis vary much according tothe duration and form of the inflammation. In the fresh state themost conspicuous objects are the products of degeneration of thefibres, granules and masses of myelin, and granule corpuscles, with,in older cases, the peculiar bodies termed corpora amylacea(Fig. 93, cZ). With these are numerous red blood-discs, leucocyte-like corpuscles, and, after the first week, distinct cells, round, oval,spindle-shaped, or angular, with nuclei which resemble leucocytes insize, and are readily mistaken for them. Fragments of axis-cylindersmay also be seen, granular in aspect, and with irregular swellings(Fig. 93,a). ACUTE MYELITIS. 305. od The softened and even diffluent state of the tissue prevents us fromlearning much, hj microscopical examination, of the condition of theparts in which the inflammationis intense and diffuse, becausethe breaking up of the tissueand separation of the fragmentsrenders it impossible to obtainsections of the hardened is only where the inflamma-tion is less intense, or less uni-formly diffused, that a thoroughexamination can be made. Theproducts of degeneration arebest seen in the fresh state or insections mounted in glycerine(Fig. 93). The fragments andglobules of myelin in part occupythe position of the nerve-fibresfrom which they have come,in part are aggregated intomasses. In sections rendered trans-parent in the ordinary way,the fatty products of the de-struction of the nerve-elementsare invisible, and the most con-spicuous alterations are the dila-tation of vessels, which is oftenvery great, and the accumulation of leucocytesel
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnervoussystem, bookye
