602 DR JAMES W. DAWSON ON 



both are affected. The sclerotic areas in these regions are amongst the most constant 

 appearances in disseminated sclerosis, and may be related to the early eye changes 

 so frequently found clinically. 



(b) Changes in the Nerve Roots, Cauda Equina, and Peripheral Nerves. 



Changes in the nerve roots are comparatively seldom referred to in the literature 

 of disseminated sclerosis, and where noted they are usually described as insignificant. 

 Dinkler, however, in one case found the whole of the spinal cord roots thickened 

 near the cord ; Schob, in addition to fibroma-like thickenings of the nerve roots, 

 describes discontinuous areas of myelin degeneration in non-glious containing tissue, 

 and Strahuber and Marburg have reported similar findings. These areas contained 

 a connective tissue proliferation of the endoneurium and a proliferation of the 

 Schwann's sheath in place of a neuroglia sclerosis. In one peripheral nerve similar 

 discontinuous areas were found. 



In this investigation the nerve roots in only one case were systematically 

 examined in longitudinal section, but in several other cases portions of the nerve 

 roots remaining attached to the cord segments (figs. 125-128 ; 240) reached the 

 length of one-half centimetre, and in other cases very numerous ganglia (fig. 227) 

 were examined with nerve roots attached, and in most of the cases the cauda equina 

 (fig. 92) was examined in longitudinal sections extending from two to three centi- 

 metres. In the frequent neuroglial involvement of the intra-medullary portion of the 

 cranial nerves, the extra-medullary portion seldom shared. The loss of myelin or 

 the deficient staining of the myelin extended often for a short distance into the nerve 

 roots, and then these resumed the normal staining. The extent of this demyelination 

 and neuroglial involvement of the nerve roots varied greatly, and it was looked upon 

 as proportionate in extent and form to the varying degree in which the glia normally 

 passed into the nerve roots. In the spinal nerve roots, however, especially in the 

 posterior roots of the lumbar cord, this limit was frequently overstepped, and small 

 circumscribed areas of neuroglial sclerosis were found, as if the glious zone had 

 extended far into the normally non-glial portion of the root (see figs. 263, 264). 

 Serial sections showed that these areas were very minute and that the axis cylinders 

 passed through them. 



In addition to these small areas of sclerosis, there were frequently found in the 

 fibres of both cranial and spinal nerve roots three other types of changes : (l) a 

 diffuse change comparable to the "shadow" staining of the myelin in the central 

 nervous tissue ; (2) a definite secondary degeneration of isolated fibres or groups of 

 fibres (fig. 451), related probably to the loss of the axis cylinder in a sclerotic area; 

 and, finally (3), in Marchi sections, as already mentioned, the nerve roots shared in 

 an early degree of myelin degeneration, which affected the whole transverse section 

 of many cord segments — a change which is probably related to the presence of a 

 terminal infection. Orr and Rows have demonstrated the evidence of a continuous 



