THE SYMPATHETIC SYSTEM 333 



B. PUPILLARY CHANGES. 



Pupillary changes are noticed: 



1. In nervous affections: pachy meningitis, hem- 

 orrhages in the meninges, acute meningitis, myosis precede 

 the mydriasis. During the course of an epileptic convul- 

 sion the pupil is dilated and fixed while at the same time 

 the face is pale. 



2. In Basedow's disease the classical authors admit 

 that the pupils are equal. However, Cantonnet has 

 noticed a unilateral dilatation of the pupil in 14 out of 18 

 cases of Basedow's disease by means of the "provoked 

 mydriasis" test. This consists in the examination in a 

 dark room of the pupils, in from 8 to 15 minutes after the 

 instillation of a 4% solution of cocaine in both eyes. 



3. In pleuro pulmonary affections the modifications 

 of the pupils are important symptoms. 



The Claude Bernard syndrome can be noticed as a 

 whole, but it is more often found to be dissociated. On 

 the side affected can be noted: a myosis, a decrease in 

 size of the palpebral fissure, a retraction of the eyeball, 

 the vaso-motor disturbances however are absent. In other 

 cases the oculo palpebral syndrome is absent. There is 

 only a dilatation of the pupil, associated with vaso-motor 

 disturbances of the cheek and of the ear. This may pre- 

 cede mydriasis several months or several years (Sergent). 



Finally, inequality of the pupils may occur alone with- 

 out any ocular or vaso-motor disturbances. 



These pupillary modifications in the course of pleuro 

 pulmonary affections are due to two pathogenic mechan- 

 isms. Some, such as mydriasis, observed in pleurisy with 

 effusion are of reflex origin, according to the law of Schiff : 

 all peripheral sensory stimulation causes dilatation of the 

 pupil. The others are explained by the anatomical 



