424 DISEASES OF THE EYES 



and greenish coloration of the i)upiL Treatment consists of a few drops 

 of physostigmin sohition 1 to 100, which tends to reduce the intraocuhir 

 pressure, and puncture of the cornea. In chronic hydrophthahiius the 

 entire eyeball had best be removed. Iridectomy is performed in man 

 for glaucoma and Gra>fe has recommended it for the dog. 



Diseases of the Vitreous Humor. — These are generally congenital 

 and are observed with the ophthalmoscope. The vitreous humor is found 

 on examination to be filled by a filiform or striated opacity; in some cases 

 the vitreous humor is found to be a mobile liquid. There are a number of 

 other changes, but this condition is incurable, and merely for diagnostic 

 purposes, consequently, works on the eye are to be consulted. Of these 

 diseases there are a number of anomalies, but the most important are 

 hemorrhage of the retina, inflammation of the papilla of the optic nerve, 

 and detachment of the retina, total cataract and a partial luxation of the 

 lens, licpefaction of the vitreous humor of the eye, swelling of the papilla, 

 and injection of the vessels of the retina. 



Hemorrhage of the Retina. — This may be caused by violent trau- 

 matism and from certain diseases such as scurvy, ptomaine poison and 

 from poisoning from male fern extract given for tape-worm. Those 

 which are only visible with the ophthalmoscope are round, irregular line- 

 like bodies, brownish-yellow, which gradually become light yellow or 

 white. Treatment is generally useless. Rest, moist, warm compresses, 

 the application of a 1-per cent, solution of iodide of potassium, a few 

 drops in the eye once or twice daily. 



Inflammation of the Papilla of the Optic Nerve (Papillitis, Neuritis 

 Intraocular is). — This is apt to be found associated with pathological con- 

 ditions in the other structures of the eye from certain infectious diseases — ■ 

 distemper, septicaemia, ptomaine poisoning, and rarely traumatisms. 

 The papilla when examined by the ophthalmoscope is found to be hyper- 

 aemic, with more or less projection of the papilla, and congestion of 

 the surrounding vessels. When the active symptoms subside the 

 papilla atrophies, becomes grayish-white and becomes oval or circular. 



The treatment consists in keeping the animal in a dark room, 

 administering strychnine and local applications of sedatives, and small 

 doses of calomel. 



Detachment of the Retina {Amotio Retincr). — This is indicated by 

 more or less separation of the choroid and opacit}^ of the vitreous humor 

 when there is complete separation of the retina; the whole body becomes 

 converted into a funnel-like body. This condition has been observed 

 quite frequently. Moeller has found numerous cases of detachment of 

 the retina, and could find no predisposing cause. 8ubretinal cysts are 

 occasionally found in the retina? of old dogs, and present the same symp- 

 toms as this disease. Treatment is useless. 



