PARTIAL SCLEROSIS OF THE BRAIN. 261 



divided. On microscopical examination we find amorphous fine gran- 

 ular masses along with well-preserved nerve-elements in the milk-white 

 indurated spots. In the grayish-red prominences, on the other hand, 

 there are no nerve-elements ; they consist of a filamentary mass and 

 the remains of capillary walls, in which fat granules are embedded 

 ( Valentiner). 



The symptoms and course of partial sclerosis of the brain are not 

 so characteristic as to render the disease easy of recognition ; on the 

 contrary, it must be regarded as a triumph in diagnosis, that this has 

 been done in a few cases (Frerichs). Since the sclerosis is limited to 

 scattered and circumscribed points and develops slowly, the paralyses 

 accompanying the disease have the peculiarity that, in the commence- 

 mejnt at least, they do not extend over one-half the body, but always 

 begin in single groups of muscles, or in a single extremit}'- (always 

 one of the lower extremities), and thence extend gradually to other 

 groups of muscles and other extremities, till finally the central parts 

 governing respiration, deglutition, and the actions of the heart, are 

 affected. This extension is not regular : for example, paralysis of the 

 right hand does not necessarily follow that of the right foot, but it is 

 entirely lawless. This fact in itself speaks in any case for the depend- 

 ence of the paralysis on numerous separate points of disease, and 

 not on one gradually-increasing spot. Besides the paralyses, which 

 are the most 'constant, and, from their peculiar mode of extension, the 

 most characteristic symptoms of partial sclerosis of the brain, there are 

 also disturbances in the other functions, but these are far less distinc- 

 tive and less characteristic of the disease. Headache is absent in most 

 cases ; but there are often peripheral pains, and a feeling of formica- 

 tion in the extremities which is followed by a diminution of sensation, 

 increasing to perfect anaesthesia. The special senses are rarely affected, 

 and among these that of sight almost exclusively. In most cases there 

 are moderate symptoms of irritation in the psychical functions ; but 

 these are soon followed by a gradually-increasing deep depression, 

 which in some Ceases exists from the first. Convulsions only occur 

 exceptionally ; but trembling is a very constant symptom. The nutri- 

 tion of the body is not generally affected till late in the disease, and 

 in some patients, just as in encephalitis, there is even a remarkable 

 development of fat. The course of the disease is very tedious ; most 

 of the cases observed lasted from five to ten years. During this time 

 the disease occasionally appeared to remain at a stand-still, but no 

 existing paralysis was ever observed to disappear. No instances of 

 recovery are known. In the cases that have been described, death 

 resulted partly from the extension of the disease to the medulla ob- 

 longata and consequent disturbance of the respiration, partlv from 



