. The elements of pathological histology with special reference to practical methods . filledup partly with fiuid and partly with growing neuroglia. At theearliest period the degenerated tracts still contain many of the pro-ducts of disintegration, and hence to the naked eye are white andsofter than normal. Later the supporting tissue gradually increasesin amount, and its spaces become progressively smaller, but isolatedgranule corpuscles are always still present. At this stage theaffected tracts appear grey to the naked eye. As regards primary degeneration, the histological conditions areanal
. The elements of pathological histology with special reference to practical methods . filledup partly with fiuid and partly with growing neuroglia. At theearliest period the degenerated tracts still contain many of the pro-ducts of disintegration, and hence to the naked eye are white andsofter than normal. Later the supporting tissue gradually increasesin amount, and its spaces become progressively smaller, but isolatedgranule corpuscles are always still present. At this stage theaffected tracts appear grey to the naked eye. As regards primary degeneration, the histological conditions areanalogous to those in the secondary variety. Here also we have an TABES DORSALIS 337 atrophy of the nerve-fibres ushered in by disintegration of themedullary sheaths, and accompanied by formation of granule cor-puscles and growth of the neuroglia. It is only questionable whetherthe latter or the disappearance of the nerve-fibres is the primarylesion. Primary degeneration occurs with greatest frequency in the pos-terior columns, and is then called tahes dorsalis, or grey degeneration A. B Fjo. 1(53.— Section through the Simnal Cord in Tabes low power. (Wcigcrts hajmatoxylin.) A, Normal anterior columns ; B, Normallateral columns; C, Posterior columns, for the most part in a state of greydegenerattion. of the posterior columns (Fig. 163). In this disease the first partsto be affected are the central portions of the columns of Burdachin the lumbar and dorsal regions of the cord, and the medianportions of the columns of GoU in the dorsal and cervical regions,as well as also the posterior nerve-roots. Subsequently the otherparts of the posterior columns are also involved, especially in tlielumbar and dorsal segments, only the most anterior parts im-mediately adjacent to the posterior commissure appearing almostalways intact, or at all events less altered. The degeneration mayspread, on the one hand upwards along the funiculi graciles to thefossa rhomboidalis,
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectpatholo, bookyear1895
