. Diseases of the nervous system . of spinal cord in the medulla is permeated by such foci. With Weigertsglia stain they are perhaps evenmore prominent than with the me-dullary sheath stain; for we thenoften recognize numerous, micro-scopically small foci which wouldotherwise not be visible. Muchlarger foci are seen in the shapeof round or angular circumscribedspots irregularly disseminated likedefects in the nervous substance,and these appear as if they hadbeen pierced with a stiletto. Thechronic myelitic process of this dis-ease is very conspicuous and does notespecially attach th
. Diseases of the nervous system . of spinal cord in the medulla is permeated by such foci. With Weigertsglia stain they are perhaps evenmore prominent than with the me-dullary sheath stain; for we thenoften recognize numerous, micro-scopically small foci which wouldotherwise not be visible. Muchlarger foci are seen in the shapeof round or angular circumscribedspots irregularly disseminated likedefects in the nervous substance,and these appear as if they hadbeen pierced with a stiletto. Thechronic myelitic process of this dis-ease is very conspicuous and does notespecially attach the axis cylinder. This is retained to a great extent, and precludes those secondary changes whichwe invariably see when the nerve fibers are completely destroyed (Figs. 116,117).Those authors are probably correct who designate the disease as origin from the nervous substance may be excluded, but the implicationof the vessels is secondary, the seat of the foci by no means correspondingwith their course and Fig. 117.—Multiple Sclerosis. G. SECONDARY DEGENERATIONS In pathologic processes of any organ certain distant effects are produced,so that the surroundings of parts not directly affected may show certaininflammatory or degenerative alterations. In the central nervous system, OTHER DISEASES OF THE CENTRAL NERVOUS SYSTEM 121 however, other damage may be explained by the intimate anatomical relationof the neuron constituents. What Waller once designated as roots of thespinal cord, the anterior of which, corresponding to their course, are centrif-ugal, and the posterior centripetal, is true of every tract of the brain andspinal cord. Section and interruption of the conduction tract and the conse-quent separation from the nourishing cell invariably destroy the peripheralportion of the neuron. This degeneration is intense and irreparable providedcommunication is not restored. Moreover, central disturbances occur, butthese, as I have several times stated,
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectnervoussystem, bookye
