SPASM OF PERIPHERAL NERVES. 



349 



but they do not sneeze when the nasal mucous membrane of the at- 

 fected side is irritated, since no reflex action upon the respiratory ap- 

 paratus can be set up in this region. Nutritive disorders of the affect- 

 ed side are associated with these symptoms, similar to those which 

 may be provoked artificially in the lower animals by extirpation of the 

 ganglion of Gasser, such as varicosities of the eye, with ulceration and 

 atrophy, fungous flabbiness of the gums, bleeding from the mouth and 

 nasal cavities, blueness and oedema of the cheeks. In contrast to the 

 observed cases of " ageustia," there are a good many others in which 

 the sense of taste remained normal. The sense of smell and of vision 

 often suffers ; but in such cases it is difficult to say what part the 

 disorders of the nasal mucous membrane and bulb above referred to 

 play hi producing such impairment of function. If both portio major 

 and portio minor of the trigeminus be destroyed, in addition to the 

 palsy of sensation of one side of the face, there will be palsy of the 

 muscles of mastication upon that side. If the destruction of the gan- 

 glion be caused by the presence of a large tumor or other extensive 

 disease affecting the base of the skull, the function of other cerebral 

 nerves is likewise usually disturbed, especially that of the oculomoto- 

 rius, the facial, the acoustic, and there are ptosis, dilatation of the pupil, 

 palsy of the corresponding side of the face, and deafness of the ear of 

 that side. 



If but one branch of the trigeminus, instead of the whole nerve, be 

 diseased, the anaesthesia is limited to the region of the face which is 

 supplied by that branch ; if it be the first branch, to the socket of the 

 eye, the second to the nose, the third to the cavity of the mouth. If 

 the affection be confined to a few twigs alone, the insensible parts of 

 the face are still smaller, and the cavities may be normal. 



An isolated central anaesthesia of the trigeminus without, simultane- 

 ous anaesthesia of the corresponding half of the body, is one of the 

 greatest of rarities. In a previous chapter we have stated the chief 

 means of distinguishing such a case from a peripheral anaesthesia. 



With regard to treatment, we must also refer to what has already 

 been said of the treatment of anaesthesia in general. 



SPASM INVOLVING- PARTICULAR PERIPHERAL NERVES. 



IN the following chapter we shall treat of the morbid conditions of 

 excitement to which the various motor nerves are subject. Just as ex- 

 citement of a nerve of sensation is evinced by a feeling of pain and by 

 reflex symptoms, so that of a motor nerve is indicated by contraction 

 of the muscle which it supplies. If the motor nerve be acted upon bv 



