538 DR JAMES W. DAWSON ON 



(3) More Recent Researches, 1903-1913. 



Bielschowsky (1903) has investigated five cases of disseminated sclerosis by 

 means of a silver-impregnation method for axis cylinders (see p. 555). He found 

 in sclerotic areas axis cylinders preserved in such large numbers that the areas 

 could scarcely be distinguished, in consequence of the numbers of axis cylinders 

 running in normal order and with normal calibre. The presence of thickened vessels 

 in the sclerotic areas alone served to indicate the patch. In other areas the axis 

 cylinders were sinuous and swollen or split up into a bundle of parallel-arranged 

 fibrils, or, again, broken up into a series of pearl-like swellings. Bielschowsky 

 discusses the question of the axis cylinders present being regenerated or persistent 

 axons, and comes to the conclusion that they must be chiefly persistent. He bases 

 his view chiefly on the facts that the topographical arrangement of the fibres is 

 maintained, and that in longitudinal section myelin fibres could be traced directly 

 into the sclerotic tissue, there to lose their myelin sheath and again to become 

 connected with myelinated fibres at the limit of the area. Bielschowsky states 

 that there was a far-reaching correlation between the clinical histories and the 

 impregnation pictures, and claims that, by his method, the relationship between 

 symptoms and anatomical findings is made more evident than by any other method. 

 He thinks that the finest axis cylinders disappear first, the coarser ones being pre- 

 served longer, but admits that the coarser axis cylinders may be swollen fine ones. 

 The possibility of a slight regeneration of nerve fibres is admitted, fork-like divisions 

 being probably regeneration appearances, and brush-like splitting up probably 

 degeneration signs. 



Bielschowsky regards the nature of the process as essentially an inflammatory 

 one, attacking both the parenchymatous and interstitial tissues, but affecting the 

 nerve fibre more uniformly than the glia. He looks upon the vessel changes as 

 secondary to the resorptive processes, and thinks that the circulating "noxa" passes 

 through the vessel wall, leaving it intact. 



Bartels (1904) has examined four cases of disseminated sclerosis, and supports 

 Bielschowsky's view of the persistence of the axis cylinders in opposition to 

 Strahuber's view of the regeneration. By means of Kaplan's, Strahuber's, and 

 Bielschowsky's staining methods, he has demonstrated the direct transition of the 

 fibres within and without the foci. He considers that the fibres stained with aniline 

 blue are those in which the myelo-axostroma (axo-chromatenin) survives the 

 destruction of the myelin sheath. 



Strahubrr (1903) thinks that the disposition to disseminated sclerosis might be 

 occasioned by inborn defects as well as by minimal tissue injuries that have arisen 

 in the place of earlier injuries or local anaemias. Such parts are "loci minoris 

 resistentise " for bacteria or toxins reaching them from the blood. On the other 

 hand, bacteria or toxins in the blood, in consequence, for example, of infectious 



