GENERAL THERAPEUTICS OF DISEASES OF THE EYE 



Pathology. — In the treatment of the different diseases of the 

 eye numerous therapeutic methods come into consideration. Dis- 

 eases of the Uds, conjunctiva and cornea are treated with anti- 

 septics (boric acid, salicyUc acid, chlorine water, quinine), as- 

 tringents (zinc sulphate, silver nitrate), caustics (copper sulphate, 

 oxide of mercury, cauterization) and narcotics (cocaine, eucaine, 

 alypin, ansesthesin, orthoform); also by operation (entropion 

 operation), massage (corneal opacity), hydrotherapy, etc. In 

 paralysis of the optic nerve, excitants (strychnine) and electro- 

 therapy are employed. Finally, there is a group of medicines 

 which are usually designated as eye remedies in the restricted 

 sense. These are the pupil-dilating (mydriatics) and the pupil- 

 contracting (myotics) agents. 



1. PUPIL-DILATING REMEDIES. MYDRUTICS 



Actions and Uses. — The artificial dilation of the pupil by 

 atropine, scopolamine (hyoscine) and homatropine is the result of 

 paralysis of the oculomotor nerve the motor nerve of the sphincter 

 of the pupil. The mydriasis is usually produced by the direct or 

 local action of the drug by introducing the latter into the con- 

 junctival sac; dilation of the pupil by the internal administration 

 of the mydriatic is of no practical value. 



The purposes for which mydriatics are used are very variable. 

 Therapeutically, they are employed in iritis to prevent or loosen 

 adhesions of the iris to the capsule of the lens. For this reason, 

 they are of the greatest importance in the treatment of periodic 

 ophthalmia in the horse. They are also used to prepare the eye for 

 some operations, especially the cataract operation and iridectomy. 

 They are not less important for diagnostic purposes, when it is 

 desired to examine the interior of the eye, the artificial dilation of 

 the pupil facilitating the examination of the interior with the 

 ophthalmoscope. In this way turbidity of the vitreous humor 



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