. Diseases of the nervous system . of glia cells are produced that they cause displacementphenomena (so-called gliosis or primary gliosis) or an extensive tumor forma-tion (gliomatosis, gliomata). The central canal is often situated in front of the cavities and spacesalthough commonly filled with those ependymal cells which are quite fre-quently found in the normal cord of adults. Therefore, in such cases we can exclude simple dilatation of a normallysituated central canal in the walls and surroundings of which destructive andproliferative processes have been generated, and other morbid states
. Diseases of the nervous system . of glia cells are produced that they cause displacementphenomena (so-called gliosis or primary gliosis) or an extensive tumor forma-tion (gliomatosis, gliomata). The central canal is often situated in front of the cavities and spacesalthough commonly filled with those ependymal cells which are quite fre-quently found in the normal cord of adults. Therefore, in such cases we can exclude simple dilatation of a normallysituated central canal in the walls and surroundings of which destructive andproliferative processes have been generated, and other morbid states must beconsidered. In the first place minute anatomical investigations have demonstrated thatseveral central canals may develop and be situated behind each other, and thatconsequently an extensive diverticulum of the central canal may be formedsimilar to that observed in the esophagus. A number of cases make it seem extremely likely that syringomyeliticprocesses may readily develop from such diverticula and auxiliary cavities. In. Fig. 176.—Syringomyelia of the Cervical Enlargement. The white substance is stainedblack by Weigerts stain. The entire gray substance is changed, destroyed, or permeatedwith cavities. Even in the posterior horn, only a part of its contour is normally retained. other instances no such anomalies can be found, and we must assume thatsyringomyelia may develop also in a normal spinal cord. Nevertheless, wemust finally inquire how these anomalies of development arise, and whetherin the growing cord, at birth or later, other disturbances may not naturallydevelop which finally lead to progressive syringomyelia. The cavities andspaces are not necessarily the primary condition but may arise it is possible that tumors of a gliomatous nature may develop from theependyma or from other parts of the glia substance and gradually break upin the center, thus causing these secondary cavities sooner or later to com- SYRINGOMYELIA 589 municate with the
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectnervoussystem, bookye
