THE HISTOLOGY OF DISSEMINATED SCLEROSTS. 715 



General Characters of the Areas (Plate LIX). 



The marked involvement of the spinal cord and the comparative integrity of the remain- 

 ing portion of the central nervous system are the striking features of this case. Micro- 

 scopically it was evident that the cervical and dorsal cord were almost completely sclerosed, 

 but no areas could be so recognised after a careful examination, even of mordanted blocks, 

 of the medulla, pons, mid-brain, and hemispheres. Several levels of all of these portions were, 

 however, cut in celloidin sections, and microscopic examination proved the presence of a 

 few isolated areas throughout the brain stem and hemispheres. These were related to the 

 pons, chiefly to the root-entry zones of the VHIth nerve and to the superior cerebellar 

 peduncles : in the hemispheres there was a very slight peri-ventricular sclerosis around 

 the posterior horns, a very few subcortical and cortical areas, and an extensive demyelina- 

 tion of the superficial layers of the cortex over several convolutions. 



The segments of the cervical enlargement showed an almost complete and advanced 

 degree of sclerosis throughout their whole extent (figs. 209-211). A similar advanced 

 sclerosis was present in the dorsal cord (figs. 212-214), and this was almost as extensive, 

 especially in the upper and lower dorsal regions. The densest sclerosis was again present 

 in the central portions of the posterior and lateral columns. Marchi sections of numerous 

 levels showed that very few fat granule cells were present, and that these were almost 

 restricted to the walls of the peripheral vessels ; there were no ' ; early " areas present at 

 any level. Bielschowsky- and Cajal-stained sections proved that numerous axis cylinders 

 were absent and that many of those persisting stained faintly. The ganglion cells were 

 very atrophic, but amongst them were found rounded forms with chromophile granules 

 almost normal in structure and arrangement. The nerve roots were normal at most levels 

 (figs. 209-211), but a few showed slight rarefaction. The membranes were practically 

 normal. 



Topographical Distribution. 



Spinal Cord.— Cervical Region (figs. 202-203 and 209-211). — In the first (fig. 203) and 

 second segments there are traces of early involvement on each side of the anterior fissure, 

 in the region of the crossed pyramidal tracts, and in the columns of Goll. At the third 

 segment (fig. 202) three well-defined areas are present — each with a zone of lighter staining 

 around it. These lie, one in the posterior, and the others in the antero-lateral columns. 

 A small dense peri-central area is also present, and there is a marked widening of the glia 

 border zone, especially over the anterior surface of the cord. At the sixth segment t v e 

 whole transection shows a dense sclerosis, with the exception of a few symmetrically-placed 

 fibres near the posterior root-entry zone and a group of lateral peripheral fibres on one side. 

 At the seventh segment the sclerosis is almost as complete, but the preserved groups of fibres 

 are larger and reach, on one side, diagonally into the substance of the cord from the anterior 

 and posterior root zones. On the opposite side the areas are smaller but similar in position. 



Dorsal Region (figs. 212-214). — At the first dorsal segment the sclerosis is still very 

 complete : on one side anteriorly a broad band of peripherally-placed fibres and poste- 

 riorly a peripheral zone, lying between the tips of the posterior horns, escape. Between 

 these four deeply-sclerosed segments of the cervical enlargement (C6-D1), the sections all 

 show an almost complete demyelination with the exception of peripheral groups, varying 

 slightly in size and position, but often placed symmetrically. The whole of the upper dorsal 

 cord shows a marked degree of sclerosis, but in the mid-dorsal region the form of the areas 

 becomes more irregular. A peri-central sclerosis forms the centre, from which radiate 

 in all directions more or less marked areas : the largest of these cuts across the grey matter, 

 and occupies almost the whole of one antero-lateral column, allowing peripheral anterior 

 and direct cerebellar tract fibres to escape. A second area extends along the posterior 



