546 DR JAMES W. DAWSON ON 



to a much more chronic process in which an endogenous factor — an increased 

 tendency to glia hyperplasia — has played a part. In the brain there were no areas 

 corresponding to this diffuse gliosis. 



In a later paper (1910) Volsch returns to the question of the differential 

 diagnosis between disseminated sclerosis and disseminated encephalo-myelitis. He 

 states that both in acute and chronic multiple sclerosis he has found peri-vascular 

 areas brought about directly by an exogenous " noxa," but that he cannot regard 

 the glia hyperplasia as solely secondary and reparatory. On account both of its 

 rapid onset and its profuseness, he assumes that the exogenous "noxa" causes 

 nerve fibre degeneration, and at the same time stimulates the glia to proliferate. 

 In this proliferation such an endogenous factor as a congenital predisposition of the 

 glia to hyperplasia might play a role. 



Oppenheim (Gtjstav) (1908) investigated histologically four cases of disseminated 

 sclerosis. Successive sections of various parts of the brain and cord were stained 

 by the various elective staining methods in order to obtain as complete and 

 simultaneous a picture as possible of the changes in the component tissue elements. 

 He was able to confirm the usual findings as to myelin sheath degeneration, relative 

 integrity of the axis cylinders, and the frequent presence of fat granule cells in the 

 sclerosis area. In three of the four cases examined there was marked plasma-cell 

 infiltration of the walls both of arteries and veins. The presence of the plasma 

 cells, the author regards as an expression of a more or less chronic inflammatory 

 process. With the Weigert glia stain areas of a dense sclerosis were noted, together 

 with those of a looser structure, the latter containing many large spider cells. A 

 special study was made of the cortical areas, and those involving both cortex and 

 subjacent white matter. While the subcortical portion of these patches presented 

 a more or less dense feltwork of neuroglial fiibres, in the cortex itself this fibre 

 increase ceased, except in the Randzone, and in the ganglion-cell layers only single 

 spider cells were found. It was almost impossible to distinguish the cortical areas in 

 the preparations stained by Nissl's and Bielschowsky's methods, on account of the 

 persistence of the nervous elements : the glia fibril picture also was negative in 

 the cortical area and positive in the subcortical white matter. The statements of 

 those observers who worked with nuclear stains alone, — before the introduction of 

 Weigert's medullated sheath stain, — to the effect that the subcortical patches did 

 not extend into the cortex, is thus explained. Oppenheim has found in these 

 cortical areas, in addition to the absence of the myelin sheaths, a diffuse, ex- 

 cessively delicate, protoplasmic reticulum. In spite of the similarity of this net- 

 work to Held's diffuse protoplasmic glia reticulum, he doubts whether it can be 

 looked upon as exclusively of glious structure. 



Benioni (1908) describes a case in which there was complete absence of any of 

 the classical symptoms of disseminated sclerosis, except intention tremor. Sclerotic 

 areas were found only in the spinal cord, and there was a marked alteration of the 



