1923- ^^0. 1 6. THE NEUROLOGICAL ASPECT OF LEPROSY. 25 



The same current applied to symmetrical points, each 2,6 centimetres 

 removed from the corresponding motor points in the downward and medial 

 direction, gave the following results : 



/7^/// sidle Ifft side 



K. C. C. + K. C. C. -t- 



A. C. C. ^ A. C. C. + 



The contraction was in both cases a trifle slower on the left than on 

 the right side; but the difference was not great, - and the anodic contrac- 

 tion was in no case stronger than the cathodic contraction. Thus only by 

 carefully comparing the two sides and carefully measuring the current 

 employed was it possible to ascertain that the response to electrical stim- 

 ulation was not normal on the left side. 



The other cranial nerves do not play any great rôle in the semeio- 

 logy of lepros}'. 



As regards the ist cnDiial )ien'e (the olfactory nerve) Hansen »!v: Looft 

 state that in advanced cases of the maculo-anaesthetic form the sense of 

 smell is as a rule diminished or entirely lost. 



The second cranial nen'C Inervus opticus) is very often impossible to 

 examine on account of the frequent lesions in the cornea (sometimes of a 

 primary, sometimes of a secondary nature). This latter aftection of the cornea 

 has been described as keratitis ex lagophtalmo (L. Borthex) and probabh- 

 the lagophtalmus plays the most important rôle in the pathogenesis; but 

 the trigeminal affection has no doubt also a great share in its causation — 

 as the trigeminal aftection abolishes the conjunctival and corneal sensation, 

 and thus does awav with the protective reflex mechanism which depends 

 on corneal and conjunctival stimuli. When blindness occurs in leprosy it 

 is, as a rule, due to alteration of the cornea or of the iris. 



On account of this loss of eyesight it is also very difficult to examine 

 the function of the third, fourth and sixth nen<es. (Nervus oculomotorius, tro- 

 chlearis and abducens). As a great rule they are not affected. A real 

 ptosis is practically never met with. What sometimes gives the impression 

 of ptosis, is a partially and continuously executed Bell's phenomenon in 

 cases of lagophtalmus with hypersensitiveness to light. I have never found 

 a real nystagmus, but 1 have met with several cases of irregular nystag- 

 moid jerks. 



That some of the cases have been rather deaf, and that this deafness 

 has had the character of a nerve deafness, is true; but 1 have no reason 

 to declare this deafness to be the result of any leprous aftection of the 

 eighth nen'C. Particularly do I wish to point out that in many of the cases, 

 where the facial affection was most pronounced, the hearing had remained 

 quite good. 



