1923. No. 16. 



THE NEUROLOGICAL ASPECT OF LEPROSY. 



13 



My personal observations comprise 63 cases. A few were referred to 

 the outpatient department of my section at Rikshospitalet by my colleague 

 Professor Bruusgaard. Most of the cases I have examined at the leprosy 

 hospitals in Bergen, and have to thank Dr. H. P. Lie for his valuable help 

 and assistance. 



Cranial Nerves. 



As regards the cranial nerves the fifth and the seventh are the ones 

 most frequently aftected. 



The fifth cranial nerve (the trigeminal nerve) consists, as is well known, 

 of a sensory division, supplying the face and anterior part of the scalp — 

 and a motor division, supplying the muscles 

 of mastica on. In leprosy the disturbance 

 is as a rule confined to the sensory division. 

 Only in two cases have I found a unilateral 

 motor trigeminal paralysis.* 



The sensation of the different parts of 

 the face are often affected to a very different 

 degree. In initial cases the whole trigeminal 

 area is rarel}' anaesthetic. Fig. 2 is a typical 

 illustration of the distribution of the anaesthesia 

 or hypoæsthesia. 



As a rule the different qualities of sensa- 

 tion are equally diminished; but one also meets 

 with cases, where a more or less marked dis- 

 sociation bet\veen the different qualities of sen- 

 sation occurs. Thus there may be a marked 

 hypoalgesia, perhaps complete analgesia, to 



pinprick, whilst there is only a slight hypoæsthesia to touch or to tempera- 

 ture stimuli. All kinds of imaginable dissociations between the different 

 qualities may be met with. One even sometimes meets with cases where 

 there is a marked difference between the sensation of cold and of warm 

 stimuli. But these dissociations do not by any means occur in the majority 

 of cases, and I have never found them complete, viz. one quality quite 

 intact with another strongly diminished. To sum up: All the different 

 qualities of sensations are affected in limited fields of the trigeminal area 

 — as a rule to the same extent; but in some cases with some difference 

 as to the intensity of the loss. 



Fig. 2. Hypoaesthesia of part 

 of the trigeminal area. 



' Armauer H.\nsen has described a case of double trigeminal paralysis with dropping 

 of the lower jaw. 



