Treatise on the diseases of the eye : including the anatomy of the organ / by Carl Stellwag von Carion ; tr. from the 3rd German ed. and ed. by Charles E. Hackley and D.B. St. John Roosa ; with an appendix by the editors.
- Karl Stellwag von Carion
- Date:
- 1870
Licence: Public Domain Mark
Credit: Treatise on the diseases of the eye : including the anatomy of the organ / by Carl Stellwag von Carion ; tr. from the 3rd German ed. and ed. by Charles E. Hackley and D.B. St. John Roosa ; with an appendix by the editors. Source: Wellcome Collection.
Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.
49/810 page 27
![IRRITATING POWDERS. 21 - ones, -which are formed under more favorable conditions, and possibly in a manner more corresponding to the normal process. In certain cases of exceedingly luxu- riant production [of these layers], it is not only an advantage to increase the sepa- ration of the superficial strata in this way, but also to act somewhat on them by a chemical destruction—that is by the caustic effect. Finally, some of the irritants do service by chemically acting on certain morbid secretions, and depriving them of the harmful influence which they may exercise upon the nutrit'on of the inflamed parts in contact with them. The use of irrita- ting agents, of course, has no good object, but is rather harmful and contra-indicated, when there is an inflammation existing, having a sthenic character. Such an inflam- mation is indicated by a lively red injection, tense swelling and heat of the part, to- gether with symptoms of nervous irritation. The same is true where there is severe ciliary irritation, the increase of which causes us to fear an affection of the inner parts of the eye-ball. Inasmuch as the irritative conditions in inflammations frequently vary in degree, and may be temporarily excited or increased, by many fortuitous internal and external irritations, it is necessary to take the precaution of testing exactly the condition of the part before each application of an irritant. It should be ventured upon only when the condition shows that an increase of irritation will be salutary. In prop- erly estimating the amount of irritation, it is necessary to exclude every thing which may influence the effect of the agent used. The reaction cau-ed by irritants applied to the eye is apt to be far greater after the night's rest, after meals, and after exciting bodily and mental exertion, than at other times. Generally speaking, the morning, from one to three hours after rising, is the best time for the applica- tion, when it is made once a day. The number of irritants which may be used is very large. We may divide them, according to the method of application and the kind of effect which they produce, into:— Irritating powders, Irritating ointments, Astringent eye-washes, and Astringent caustics. Calomel stands first among the powders; it is a very mild irritant when properly used. It appears to act mechanically as well as chemically, when in contact with the chloride of sodium of the tears. It is dusted into the conjunctival sac by snap- ping it from a camel's-hair brush. In using calomel with young children that struggle very much, it is advisable to be in a sitting position. The head of the child is held between the knees of the surgeon, and while the eye is held open with the fingers of one hand, the calomel is dusted in with the other. We should take special care that none but the finest powder, and no lumps, enter the conjunctival sac. The latter act exactly as foreign bodies, and in case they remain, are changed by the chloride of sodium of the tears into the corrosive chloride of mercury; they are then extremely irritating, and occa- sionally actually cauterize the conjunctiva. As a further precaution, it is well not to evert the lower lid, and thus expose the palpebral fold during the dusting in of the calomel. Quite a large quantity may lie in the palpebral fold and cause no unpleasant sensation at first, but remain unnoticed until a severe irritation or actual cauterization has occurred. Where considerable irri- tation is seen some time after the application, the conjunctival sac should be carefully examined, and be cleaned of any remains of the powder by wiping it out. The introduction of large quan- tities cannot be sufficiently guarded against; it is sufficient when a frosty-looking coating appears on the conjunctiva and cornea. The brush should therefore be freed from the rough particles before it is used. There are some other powders much less reliable but more irritating, which have been blown into the conjunctival sac through a quill. Their use has been given up to some](https://iiif.wellcomecollection.org/image/b2107902x_0049.jp2/full/800%2C/0/default.jpg)
