Glaucoma. 427 



Complete posterior synechia acts by confining the liquid which 

 is secreted, to the posterior chamber whence it finds no ready out- 

 let through the pupil, and causes a marked bulging forward of 

 the iris and tension of the eyeball. 



Slighter anterior synechia in the form of cicatricial adhesions 

 between iris and cornea in the sclero- corneal margin, acts by 

 blocking the principal drainage canal of the aqueous humor, 

 which lies in this angle. 



Traumatic injuries implicating the capsule of the lens and ad- 

 mitting the aqueous humor freely to the lens substance deter- 

 mines softening, swelling and so much irritation as to increase 

 the secretion largely and determine intra-ocular tension. 



The same may result from luxation of the lens and irritation 

 of the ciliary circle by dragging. 



Other causes are disease (atheroma) of the retinal vessels and 

 the growth of tumors in the interior of the eye. 



Lesions. These are very varied. Inflammation of the iris, 

 ciliary body and choroid and even of the cornea is not uncom- 

 mon. The iris and ciliary body show round cell infiltration, as 

 may also the choroid. In the ciliary body this is likely to be es- 

 pecially abundant along the drainage canal (canal of Schlemm) 

 thereby reducing its calibre. I^eber and Fuchs found drops of 

 liquid in the epithelium and cornea. One of the most significant 

 lesions in man is the cupping or depression of the lamina cribrosa 

 of a depth in ratio with the force of the intraocular pressure, 

 and inflammation or atrophy of the optic nerve, back of the eye. 

 MoUer, however, has never been able to find actual cupping of 

 the optic papilla in animals, but instead thereof a general disten- 

 sion of the outer coats of the eye, a hydrophthalmos. In view 

 of the fact that these coats have the same structure and nearly 

 the same relative thickness as in man, this throws considerable 

 doubt on the supposed identity of glaucoma in man and cases 

 which have been considered such in the lower animals. The 

 comparative absence of pulsations in the retinal arteries in ani- 

 mals adds to the uncertainty. 



Treatment. Although such cases lack some of the diagnostic 

 symptoms of glaucoma in man, yet they agree with that in the 

 increase of the intraocular pressure, and demand similar meas- 

 ures for relief. Some reduction of the tension can be secured by 



