OPHTHAL3IIA ( from ophthalmos, 300aNuos, the " eye" ) is an inflammation of the eye. General ophthalmia, or an inflammation of the whole globe of the eye, is a very rare occurrence. Cases however do occur, from severe injuries or other causes, in which the signs of all the special forms of ophthalmia are combined, and they are the most formidable affections to which the eye is liable. Unless met by the most active antiphlogistie treatment, they usually terminate in com plete destruction of the organ.
In the large majority of inflammations of the eye, one part of it is alone or especially affected. Hence there have been described nume rous varieties of ophthalmia, a distinct name being formed for the inflammation of each part or tissue by appending the termination if to its anatomical name; as conjunctivitis, iritis, and corneitis, for the inflammations of the conjunctiva, iris, and cornea. [Ere, in NAT. HIST. Div.] Of all the varieties of ophthalmia, slight inflammation of the con junctiva is the most frequent. It is the common result of all slightly irritating bodies being introduced between the eyelids, and of the application of cold, in which case it is often called catarrhal ophthalmia. Its symptoms are redness, varying from a pale-pink to a scarlet colour, of the external membrane of the eye and of the lining of the eyelids, the blood-vessels (which are naturally invisible) appearing swollen and tortuous, and making the front of the eye what is commonly called bloodshot; swelling of the eyelids and increased thickness and puffi ness of the conjnnctiva of the ball ; and an increased secretion of opaque white or yellow tenacious mucus which agglutinates the eyelids. The pain is seldom acute, except in severe cases, in which it has a peculiar character, as if there were dust or fine sand rubbing between the eyelids. There is rarely any intolerance of light or any constitu tional affection, and the vision is not at all affected, except by the swelling of the eyelids and the accumulated mucus.
In this, the common inflammation of the eyes, no active manna need be employed. In severe cases, blood has been taken from the arm ; but in general, the application of leeches, cooling lotions applied to the eyes, and mild purgatives or sweating medicines, are sufficient for the removal of the inflammation, which, as it does not affect a part directly important to vision, nor spread beyond the tisane first affected, rarely leaves any inconvenience behind. In the mild cases of this kind, a
lotion composed of two grains of sulphate of zinc to the ounce of water is the beat, and generally a sufficient remedy ; the eyes should be washed with it three times a day.
That which is commonly called purulent ophthalmia is a much more serious form of inflammation of the conjunctiva. It was observed in its greatest severity in the European armies engaged in Napoleon's campaign in Egypt, and is therefore sometimes called Egyptian ophthalmia; and from its appearing to spread from one individual to another by the contact of the purulent matter secreted by the inflamed eyes, it has also received the name of contagious ophthalmia. In this form, which has often appeared as an epidemic, and is generally acknowledged to be liable to spread by contagion, all the symptoms of the preceding are greatly aggravated. The conjunctiva is intensely red, and so swollen that it is raised in a deep ring round the cornea, whose edges it overlaps so as almost totally to obstruct the sight. The conjunctiva of the eyelids is at the same time excessively inflamed, and by effusion into their loose cellular tissue they often become so dis tended that they completely cover the front of the eye. A considerable quantity of acrid yellow purulent discharge constantly flows between the eyelids, producing excoriation of them and of the checks. Tho pain is often extremely acute, vividly smarting, or hot and burning, and it is accompanied by some intolerance of light. From the conjunctiva, which it at first affects, the purulent ophthalmia often spreads rapidly to the other tissues of the eye ; producing ulceration and sloughing, or excessive opacity of the comas, and all the worst results of inflamma tion of the several tissues, even to suppuration and destruction of the whole of one or both ere-balls.