634 DR JAMES W. DAWSON ON 



may be of short duration and are usually followed by periods of remission, after 

 which a new series of symptoms may appear. Once definitely established, the disease 

 is almost invariably fatal. The great variation in the nervous symptoms has resulted 

 in a tendency, on the one hand, for any disease of nervous origin of which the 

 symptoms are unusual or difficult to interpret to be classified as " disseminated 

 sclerosis " ; while, on the other hand, the way in which the symptoms of a case of true 

 disseminated sclerosis may simulate other nervous diseases has often led to errors 

 in diagnosis. On account of the long duration of the disease in most cases, and the 

 unsatisfactory results of treatment, patients are not kept in hospital for long periods 

 of time, and thus the number of cases which come to autopsy is not large. 



The earliest symptoms of the disease are extremely variable, and depend solely 

 upon the particular part of the nervous system affected by a patch. There is, 

 however, a tendency for these patches to occur more frequently in certain regions, 

 and thus certain clinical symptoms appear more commonly than others, and as a 

 result are considered more or less pathognomonic of this condition. 



Of these symptoms one of the commonest is weakness of the legs. This is met 

 with in a very large number of cases, and is associated in most with involvement of 

 the spinal cord. It usually is progressive, and a spastic paraplegia develops. It is 

 often accompanied by a number of more or less well-defined sensory changes. Such 

 symptoms may result from one or more patches in the cervical or dorsal regions of 

 the cord, involving the descending motor and adjacent sensory fibres. If the area 

 involved be still lower, e.g. in the sacral region, then the only symptom may be a 

 sphincter involvement. These spinal symptoms may be the only ones present, or 

 they may be accompanied or followed by others due to involvement of the higher 

 centres. Of these, the principal ones most commonly found are nystagmus, alteration 

 in speech, and volitional tremor. These are largely due to want of co-ordination, and 

 are the result of sclerosis spreading in from the ventricles. 



The eye symptoms are of special importance, and are very often the first sign 

 of the disease. They often disappear quickly or may ultimately proceed to total 

 blindness. They are the result of patches in different places in the optic path, the 

 optic radiations as they pass near the descending horn of the lateral ventricle being 

 commonly involved in the peri-ventricular sclerosis. The later and more serious 

 symptoms, however, result from involvement of the more peripheral part of the 

 optic path, namely, the optic tracts and chiasma. The affection of the eye muscles 

 occurs so frequently from the close relationship of the structures innervating them 

 to the ventricular spaces, the peri-aqueductal sclerosis found in the mid-brain 

 involving the third nucleus in many cases. The nucleus of Deiters and other 

 vestibular nuclei situated at the angles of the IVth ventricle are also specially 

 liable to involvement, and there is no doubt that it is the proximity of these structures 

 to the ventricles which accounts for their frequent involvement and the special 

 diagnostic importance of nystagmus and visual symptoms. 



