CPAPTER XV. 



GLAUCOMA. 



Glaucoma. — Norton defines glaucoma as "an excess 



of pressure within tlie eye, plus the causes of and 



consequences of that excess." That place where 



the tissue of the iris, the cellular stroma of the ciliary 



body and the posterior and external portions of the 



cornea and sclera intersect, is known as the iritic 



angle (see flg. 53). This juncture combines to make a 



tissue of a fenestrated nature. These fenestra or 



openings are the Fontana spaces. The meshes of this 



tissue (just imagine a coarsely meshed fisher's net) 



merge into Deseeniet's membrane, and form the liga- 



mentum pectinatum iridis. In the sclerotic is formed, 



by the same means, the canal of Schlemm (see fig- 42), 



and all of these spaces, etc., are connecting and are of the 



lymphatics. The canal of Schlemm communicates with 



the sclerotic veins, and thus the connection between 



the anterior chamber and the circijlation is established. 



Blood is never found in these spaces physiologically. 



The zonule of Zinn, which you remember extends 



from the ciliary processes (posterior surface) to the 



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